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Home My WebLink About24IWC11-375 Maple Ave - Stormwater Management ReportSTORMWATER MANAGEMENT PLAN Proposed Trailer Storage 375 Maple Avenue Montville, Connecticut Prepared For: Town of Montville / Rand-Whitney Containerboard December 16, 2024 Prepared By: CLA Engineers, Inc. Consulting Engineers 317 Main Street Norwich, CT 06360 Ph: 860-886-1966 F: 860-886-9165 www.claengineers.com Kyle Haubert, P.E. December 16, 2024 Stormwater Management Report Proposed Retail Fuel Filling Station and Convenience Store 143 S Burnham Hwy (Route 169) Lisbon CLA Engineers, Inc. Civil · Structural · Survey STORMWATER MANAGEMENT PLAN Proposed Trailer Storage 375 Maple Avenue Montville, Connecticut Prepared for Rand Whitney TABLE OF CONTENTS 1.0 Introduction ........................................................................................................................ 1 2.0 Standard 1 – Runoff Volume and Pollutant Reduction ................................................. 7 3.0 Standard 2 – Stormwater Runoff Quantity Control .................................................... 13 4.0 Standard 3 – Construction of Soil Erosion and Sediment Control ............................. 14 5.0 Standard 4 - Post-Construction Operation and Maintenance ..................................... 15 LIST OF FIGURES Figure 1: Location Map (USGS) Figure 2: 2019 Aerial Map Figure 3: Existing Conditions Watershed Plan Figure 4: Proposed Conditions Watershed Plan APPENDICES Appendix A: NRCS Soil Report Appendix B: Hydrograph Reports - 2, 10, 25, 50, and 100-Year Frequencies Appendix C: Rainfall Data Appendix D: StreamStats Report Appendix E: Design Plan Set (Separate Document) CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 1 1.0 Introduction The project is to provide additional trailer storage space for Rand-Whitney Recycling LLC’s transportation operations, which are currently at maximum capacity. The project proposes construction of a paved storage area and access road for the storage of box trailers located at 375 Maple Avenue in Montville, CT. The parcel is recorded as Map 031 Block 015 Lot 000 and is recorded on Page 912 of Volume 690. The parcel is currently owned by 349 Maple Ave LLC, a subsidiary company of Rand-Whitney LLC. The storage area will be accessed primarily by an internal paved driveway that connects the subject parcel to Robertson Road, thus minimizing traffic impact to Maple Avenue. The driveway will be constructed on an adjacent lot to the north, which is also owned by Rand-Whitney LLC. This lot is referenced by the town assessor’s records as ‘Route 169’ and is recorded as Map 031-019-000 on Page 248 of Volume 422. For the purpose of this report, this parcel shall be referred to as ‘Parcel Route 169’. A secondary access from Maple Avenue is proposed to be constructed however, this access is intended for emergency access only and will be chained to prevent general access. The location of both parcels is shown on Figure 1, and in relation to the 2019 Connecticut orthoimagery as Figure 2. A location map is also included on the Site Development Plans. A secondary component of this project is to extend and realign the Town of Montville’s existing 30” stormwater pipe that currently discharges onto 375 Maple Avenue. The location and elevation of the pipe is currently preventing the lot from being developed. The project proposes to adjust the pipe’s alignment and create a new drainage easement in favor of the Town of Montville. This report was prepared to address the Soil Erosion and Sediment Control and Stormwater Management requirements stipulated in the Town of Montville’s Planning and Zoning Regulations. The Soil Erosion and Sediment Control Plan has been developed in accordance with the 2023 Connecticut Guidelines for Soil Erosion and Sediment Control. The stormwater management and quality has been designed in accordance with the 2024 Connecticut Stormwater Quality Manual. A full-size Design Plan Set is included separately as Appendix E. Existing Conditions Both parcels are located in an industrial zone which straddles the Oxoboxo Brook. Parcel Route 169 is approximately 34.6 acres in area and is mostly comprised of Rockland Pond; a manmade pond formed by the damming of Oxoboxo Brook in 1900. The Rockland Pond Dam (CT00242) is CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 2 owned and maintained by Rand Whitney Container. The only developed portion of Parcel Route 169 is located at its northeast corner which is used as a trailer storage area for Rand Whitney. 375 Maple Avenue is approximately 2.94-acres comprised mostly of undeveloped land located on the southwest side of Oxoboxo Brook. A residential house was originally present on the lot but has recently been raised. The land is currently cleared and ready for development. Access is from Maple Avenue only. Soils A custom soil resource report for the property was mapped using NRCS Web Soil Survey website and are listed in the table below. Soil in the area of development mainly consist of Merrimac fine sandy loam (Hydrological Group A) and Urban Fill (Hydrological Group D). Further details of the soils located on site are presented in Appendix A Wetland hydrology Two wetland areas have been identified and delineated on the project site. The first is the 13-acre watercourse and pond area comprised of Oxoboxo Brook and Rockland Pond. This wetland is a large but somewhat degraded open water ecosystem. Oxoboxo Brook flows eventually into the Thames River, a major watercourse connected with the Long Island Sound (Atlantic Ocean). No work is proposed within this wetland, but a portion of the development area coincides with the wetland’s 50-foot upland review area. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 3 The second wetland area on the project site is a small (<1ac) man-made channelized wetland in the northeast corner of 375 Maple Avenue. The channel formed as a result of the discharge of stormwater over time by the Town of Montville’s 30” storm pipe (identified on plans). This wetland appears to have existed for fewer than 50 years based on available online mapping from CTECO (although the pipe itself appears to be older than 50 years) and is not associated with any watercourse. CLA believes it to have a small impact on groundwater recharge. The wetlands principal functions and the impacts to this and downstream wetlands are evaluated and detailed in the Wetland Letter Report. Existing Watershed Hydrology An existing conditions watershed map and stormwater flow paths are included as Figure 3. The site is located in CTDEEP Local Stormwater Basin 3004-00 (Oxoboxo Brook) and drains in a northeasterly direction. Run-off from the site is directed to the Oxoboxo Brook both upstream and downstream of the dam. Run-off from the northwest portion of the site drains to Rockland Pond, which is upstream of the dam (Ex Watershed 1). The remaining southeast portion of the site drains to the downstream side of the dam before passing beneath Robertson Road and through the Rand Whitney facility (Ex Watershed 2). An existing municipal storm drain system originating from Sharp Hill Road enters the property and daylights approximately 200 feet from the southwest property line. The system comprises a 30” corrugated metal pipe that conveys stormwater from the roadway collection system located on Sharp Hill Road and Carol Drive. The drainage system is also used to collect overland flow from upgradient areas. Over the course of time, the discharge has eroded the surface soils to create a fairly uniform channel that flows east and into the Oxoboxo Brook. The periodic discharge has created a man- made channelized wetland less than 1-acre in area, running directly over the town’s sanitary sewer line and, according to the WPCA, causes unwanted infiltration issues. The town has no known rights to drain onto the property and in its current location, will interfere with the proposed CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 4 development. The project proposes to extend the pipe through the property and relocate the point of discharge to avoid conflict with the proposed improvements. Existing Watershed 1 is located at the northwest portion of the property. It comprises cleared woodland and some rock outcrops and remnants of the foundation from the raised residential house. Grades are moderate to slight. Run-off from this watershed is directed overland in a northerly direction where it eventually reaches Rockland Pond. This is considered Analysis Point 1. Analysis Point 1 – Rockland Pond Existing Watershed 2 comprises the remainder of the southeast portion of the property. It comprises cleared woodland and brush with moderate to slight slopes. Run-off from this watershed flows northeast and is intercepted by the man-made channel associated with the town’s storm drain discharge. It then follows the channel and eventually discharges to the Oxoboxo Brook immediately upstream of the Robertson Road culvert. This is considered Analysis Point 2. Analysis Point 2 – Oxoboxo Brook CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 5 Proposed Conditions A proposed conditions watershed map and stormwater flow paths are included as Figure 4. The proposed development includes construction of a paved laydown area sufficient to accommodate 61 storage spaces for trailers and paved driveways that access Maple Avenue and Robertson Road. The approximate total area of disturbance is 3.9 acres and impervious area to be constructed is approximately 2.14 acres. The proposed site improvements are depicted on the Site Improvement Plans. As previously mentioned, the Town of Montville’s existing 30” storm drain will be replaced through the limits of the site with the point of discharge relocated to the northeast, beyond the limits of paving. Stormwater Proposed Watershed Hydrology The proposed site grading will mimic existing drainage patterns and run-off from the site will continue to be directed to the Oxoboxo Brook both upstream and downstream of the dam. Run-off from the northwest portion of the site will be directed to drain towards Rockland Pond, which is upstream of the dam (Pr Watershed 1) and the southeast portion of the site will continue to drain to Oxoboxo Brook on the downstream side of the dam (Pr Watershed 2). Pr-Watershed 1 Proposed Watershed 1 comprises the developed area that produces run-off directed towards and discharges to Rockland Pond (Upstream of Rockland Pond Dam). The watershed comprises the newly developed area (Pr Watershed 1a) and the remaining undeveloped area (Pr Watershed 1b). Run-off from the developed portion of the watershed will be directed northeast and intercepted by a perimeter grass-lined swale where it will be conveyed and discharged to Water Quality Basin 1. Stormwater that leaves Basin 1 will discharge over a rip-rap lined level spreader before entering Rockland Pond (Analysis Point 1) Pr-Watershed 2 Proposed Watershed 2 comprises the remaining developed area that will ultimately discharge to the Oxoboxo Brook downstream of the Rockland Pond Dam. A portion of this watershed will be directed towards Water Quality Basin 2 (Pr Watershed 2a) and the remaining developed area comprising the Robertson Road driveway (Pr Watershed 2b) will discharge directly to Oxoboxo Brook. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 6 Hydrological Analysis: The site stormwater hydrological analysis was performed for the 2-year, 10-year, 25-year, 50-year and 100-year frequency storms using the USDA/NRCS TR-55 method to determine the peak flow rates from the existing and post development conditions. As recommended by the CT Stormwater Quality Manual, a Type D storm distribution was used. Precipitation data, rainfall intensities, and distribution were acquired from NOAA Atlas 14, Volume 10, Version 3 for the site, and is included in Appendix B. Rainfall data obtained from NOAA Atlas 14 is included in Appendix C. The soils onsite in the area of development fall into the hydrologic soil groups A and D. A copy of the soil mapping is included in Appendix A. The runoff curve numbers for the site are based on the ground cover and hydrologic soil group and are included in Table 1. Table 1 – Curve Numbers Runoff curve numbers for the existing and post development conditions were compiled from Table 2-2 of the USDA/NRCS TR-55 manual. The following curve numbers were used for the calculations. Weighted curve number calculations are included in the hydrograph reports. Existing Conditions CN Fair Condition Woods 36 Fair Condition Open Space 49 Pavement 98 Post Development CN Fair Condition Woods 36 Good Open Space 39 Pavement 98 Stormwater Management Standards and Performance Criteria The design of the stormwater management is required to meet and comply with the standards and performance criteria using non-structural Low Impact Development (LID) site planning and design techniques and structural stormwater Best Management Practices (BMPs), in addition to operational source controls and pollution prevention. The following standards are set out in Chapter 4 of the 2024 Connecticut Stormwater Quality Manual (SQM) and are intended to be consistent with the post-construction stormwater management requirements of the CTDEEP stormwater general permits, as well as local requirements within municipal planning, zoning, and stormwater ordinances and regulations. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 7 2.0 Standard 1 – Runoff Volume and Pollutant Reduction The purpose of this Standard is to preserve pre-development hydrology and pollutant loads to protect water quality and maintain groundwater recharge. For the purposes of this standard, this project is considered a new development, and therefore the Required Retention Volume (RRV) is equal to 100% of the site’s Water Quality Volume (WQV). To meet this standard, a combination of pre-treatment devices and water quality basins have been designed for the site in accordance with the 2024 Connecticut Stormwater Quality Manual to treat the proposed stormwater runoff. Proposed Watershed 1 (Analysis Point 1) Stormwater runoff from post development Watershed 1 originates from the combined discharge associated with Pr Watershed 1a and Pr Watershed 1b. Runoff from Pr Watershed 1b comprises open space with landscaping and requires no treatment. Run-off from new pavement associated with Pr Watershed 1a will sheet flow to vegetated swales that will convey stormwater to two sediment forebays in advance of entering Stormwater Basin 1. Although the vegetated swales will provide some level of pre-treatment, no credit for the stormwater’s residency time in the swales has been taken and Pre-treatment will be provided by the two sediment forebays. Two test pits (TP 1 & TP 9) were performed in the vicinity of Basin 1. TP 1 exhibited the most restrictive conditions where groundwater was observed at elevation 230.3 and mottling at elevation 231. No ledge was observed. To provide sufficient volume to address run-off volume and pollutant reduction, the bottom elevation of Basin 1 was set at elevation 231.0. The basin bottom elevation will therefore be at or close to the seasonally high-water level (SHWL). The soils in the vicinity of Basin 1 are Hydrological Group A which are conducive for infiltration. While the recommended vertical separation between the basin bottom and the SHWL will not be achieved, infiltration will still occur through the bottom and sides of the basin due to hydraulic pressure head differences. The volume of water required to be treated (WQV) and the available volume provided by the basin is calculated as follows: CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 8 Pr Watershed 1a (Basin 1) Water Quality Volume (WQV) Sizing in Accordance with Chapter 4 of the DEEP 2024 Storm Water Quality Manual Water Quality Volume (WQV) = (P)(R)(A) / 12 P = 1.3" R = 0.05 + 0.009(I) I = percent of impervious cover A = watershed area Total Watershed Area (Ac.) : 2.26 Watershed Impervious Area (Ac.) : 1.39 I = 0.62 R = 0.61 Required WQV = 0.15 Ac.-Ft = 6,453 CF Volume Provided = 18,934 CF Proposed Water Quality Basin 1 contains 18,934 CF of storage below the primary outlet elevation. This is almost three times the volume required. No flow over the primary outlet is predicted to leave the basin during a 2-year storm event and only 0.1 cfs is expected to leave basin during 10- year event. The excess volume provided is required to address Standard 2 – Stormwater Run-off Quantity Control and will be discussed in the next section. The dimensions and volume of the sediment forebays have been designed in accordance with Chapter 13 of the DEEP 2024 Storm Water Quality Manual as follows: Based on the combination of the vegetated swales and the oversized sediment forebays and treatment basins, CLA believes that the stormwater system shown on the project plans is consistent with the CTDEEP 2024 Manual. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 9 Sediment Forebay 1a Water Quality Volume (WQV) Sizing in Accordance with Chapter 4 of the DEEP 2024 Storm Water Quality Manual Water Quality Volume (WQV) = (P)(R)(A) / 12 P = 1.3" R = 0.05 + 0.009(I) I = percent of impervious cover A = watershed area Total Watershed Area (Ac.) : 0.94 Watershed Impervious Area (Ac.) : 0.59 I = 62.79% R = 0.62 Required WQV = 0.06 Ac.-Ft 2,742 CF Bottom Surface Area = 0.066 * %WQV Recommended % of WQV to be Treated 25% Minimum Bottom Surface Area = 45 sf Bottom Surface Area Provided = 225 sf Min. Volume = 25% of the WQV below the outlet invert 25% of the WQV = 685 cf Volume Provided = 1,491 cf Sediment Forebay 1b Water Quality Volume (WQV) Sizing in Accordance with Chapter 4 of the DEEP 2024 Storm Water Quality Manual Water Quality Volume (WQV) = (P)(R)(A) / 12 P = 1.3" R = 0.05 + 0.009(I) I = percent of impervious cover A = watershed area Total Watershed Area (Ac.) : 1.04 Watershed Impervious Area (Ac.) : 0.79 I = 76.18% R = 0.74 Required WQV = 0.08 Ac.-Ft 3,608 CF Bottom Surface Area = 0.066 * %WQV Recommended % of WQV to be Treated 25% Minimum Bottom Surface Area = 60 sf Bottom Surface Area Provided = 337 sf Min. Volume = 25% of the WQV below the outlet invert 25% of the WQV = 902 cf Volume Provided = 1,961 cf CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 10 Proposed Watershed 2 (Analysis Point 2) Stormwater runoff from post development Watershed 2 comprises the combined discharge associated with Pr Watershed 2a and Pr Watershed 2b. Stormwater runoff from Proposed Watershed 2a will sheet flow to a vegetated swale that will convey stormwater to a sediment forebay in advance of entering Stormwater Basin 2. Similarly, no credit for the stormwater’s residency time in the swales has been taken and pre-treatment will be provided by the sediment forebay. The volume of water required to be treated (WQV) and the available volume provided by the basin is calculated as follows: Pr Watershed 2a (Basin #2) Water Quality Volume (WQV) Sizing in Accordance with Chapter 4 of the DEEP 2024 Storm Water Quality Manual Water Quality Volume (WQV) = (P)(R)(A) / 12 P = 1.3" R = 0.05 + 0.009(I) I = percent of impervious cover A = watershed area Total Watershed Area (Ac.) : 1.04 Watershed Impervious Area (Ac.) : 0.79 I = 76.2% R = 0.74 Required WQV = 0.08 Ac.-Ft 3,608 CF Volume Provided = 5,604 cf Proposed Water Quality Basin 2 contains 5,604 CF of storage below the primary outlet elevation. This is 50% larger than the volume required. Similarly, no flow over the primary outlet is predicted to leave the basin during a 2-year storm event and only 0.1 cfs is expected to leave basin during 10-year event. The excess volume provided is required to address Standard 2 – Stormwater Run- off Quantity Control and will be discussed in the next section. Pre-treatment for stormwater flow into the basin is achieved by routing flow through an in-line sediment forebay. The dimensions and volume of the sediment forebay have been designed in accordance with Chapter 13 of the DEEP 2024 Storm Water Quality Manual as follows: CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 11 Sediment Forebay 2 Water Quality Volume (WQV) Sizing in Accordance with Chapter 4 of the DEEP 2024 Storm Water Quality Manual Water Quality Volume (WQV) = (P)(R)(A) / 12 P = 1.3" R = 0.05 + 0.009(I) I = percent of impervious cover A = watershed area Total Watershed Area (Ac.) : 1.04 Watershed Impervious Area (Ac.) : 0.79 I = 76.18% R = 0.74 Required WQV = 0.08 Ac.-Ft 3,608 CF Bottom Surface Area = 0.066 * %WQV Recommended % of WQV to be Treated 25% Minimum Bottom Surface Area = 60 sf Bottom Surface Area Provided = 233 sf Min. Volume = 25% of the WQV below the outlet invert 25% of the WQV = 902 cf Volume Provided = 1,473 cf Runoff from Pr Watershed 2b comprises the impervious area associated with the driveway between the trailer storage area and Robertson Road. Runoff from this area will be directed to a Qualifying Pervious Area (QPA) adjacent to the driveway. The SQM explains that certain areas of impervious area can be directed to natural or landscaped vegetated areas that are of sufficient size and with adequately permeable soils to disperse and retain runoff without causing erosion or negative impacts to adjacent downgradient properties. Certain criteria should be met in order for the QPA to qualify for credit. In general, the following criteria of the proposed QPA will be met: • The proposed QPA is located outside of the regulated wetland • The QPA is remote from any buildings • The portion of the QPA disturbed during construction shall receive 6 inches of topsoil and seeded with New England Roadside Matrix Mix to promote healthy vegetative cover. The remainder of the undisturbed QPA currently consists of dense vegetation covering more than 90% of the area. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 12 • To limit unnecessary disturbance to the existing vegetation downgradient of the QPA, grading has been set to 15%. This meets the maximum grade criteria for undisturbed forested areas. Although this area will initially be loamed and seeded to promote vegetative growth, this area will not be maintained as lawn and is expected to quickly repopulate with larger vegetation that will promote sheet flow residency times. Other criteria specific to driveways include: • the maximum contributing flow path from the driveway to the QPA will be 30-feet (width of the driveway). • The length of the QPA will be equal to the length of the driveway and the width of the QPA (min. 64-feet) will be more than twice the width of the driveway. • Salt tolerant New England Roadside Matrix Upland Seed Mix will be placed immediately next to the roadside. Additionally, to provide pre-treatment to the run-off, a 2-feet wide, 3-feet deep stone filled choker trench will be installed adjacent to the driveway. This will provide initial pre-treatment through nominal detention (40% stone voids), sediment retention and prevent road edge deterioration. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 13 3.0 Standard 2 – Stormwater Runoff Quantity Control The purpose of this standard is to ensure that pre-development peak flow rates are not exceeded and manage the volume and timing of runoff to prevent downstream flooding, channel erosion, and other adverse impacts, and safely convey flows into, through and from structural stormwater BMPs. To mitigate peak stormwater runoff rates due to the proposed increased impervious area onsite, stormwater will be routed through two water quality basins that have been sized to detain sufficient volumes of water to mitigate post-development peak flows. A summary of the existing condition and post development peak flow rates from the site are included in Table 2. Table 2 – Peak Flow Rates Analysis Point 1 Peak Flow Rate (CFS) per Storm Event 2-Year 10-Year 25-Year 50-Year 100-Year Existing Conditions 0.01 0.23 0.72 1.22 1.81 Proposed Conditions 0.00 0.12 0.40 0.90 1.72 Difference -0.01 -0.11 -0.32 -0.32 -0.09 Analysis Point 2 Peak Flow Rate (CFS) per Storm Event 2-Year 10-Year 25-Year 50-Year 100-Year Existing Conditions 0.01 0.17 0.63 1.24 2.08 Proposed Conditions 0.04 0.77 1.55 2.25 3.00 Difference 0.03 0.60 0.92 1.01 0.92 Site Wide Peak Flow Rate (CFS) per Storm Event 2-Year 10-Year 25-Year 50-Year 100-Year Existing Conditions 0.02 0.32 1.09 2.10 3.43 Proposed Conditions 0.04 0.75 1.59 2.34 3.22 Difference 0.02 0.43 0.50 0.24 -0.21 For Analysis Point 1, the proposed design reduces the peak stormwater flow rates in comparison to the existing conditions across all storm events. For Analysis Point 2, small increases in run-off will be realized due to the Qualifying Pervious Area not able to sufficiently detain run-off from the driveway. A USGS StreamStats report was generated for the watershed area contributing to the Oxoxboxo Brook immediately upstream of CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 14 Robertson Road (See Appendix D). The report approximates the watershed area to be 9.66 square miles with the following peak flows using the Area-Averaged Method. 2-Yr (CFS) 10-Yr (CFS) 25-Yr (CFS) 50-Yr (CFS 100-Yr (CFS) 326 608 805 978 1170 Given the significant watershed area and existing peak flows, the increases in proposed peak flows leaving the site are negligible. Hydrographs detailing the calculations are included in Appendix B. 4.0 Standard 3 – Construction of Soil Erosion and Sediment Control The 2023 CT Guidelines for Soil Erosion & Sedimentation Control applies to the construction phase of the project. A detailed erosion and sediment control plan has been provided in the site development plans. Due to the existing topography and the restrictive nature of the site, the proposed stormwater basins have been designed to function as temporary sedimentation traps during stabilization, and then to be converted to provide permanent water quality treatment for the life of the facility. While the guidelines do not recommend locating sediment traps in the proposed locations of permanent, post-construction stormwater BMPs, they recognize in some cases, this is unavoidable and require the sediment traps to be modified after their function is complete, to prepare it for long-term use. In this case, the bottom elevations of the sediment traps are designed to be at least 1-foot above the bottom floor elevation of the permanent stormwater basins, to avoid fine soil particles sealing the underlying soils. Removal of accumulated sediment and, if necessary, restoration of the pre-construction infiltration capacity of the underlying soils will be performed. Trap Capacity The temporary sediment trap shall have an initial storage volume of 134 cubic yards per acre of drainage area. Half of this volume shall be in the form of wet storage to provide a stable settling medium. The remaining storage volume shall be in the form of a drawdown (dry storage) which will provide extended settling time during less frequent, larger storm events. The dimensions and volume of the sediment traps have been designed in accordance with Chapter 5 of the Connecticut Guidelines for Soil Erosion and Sediment Control as follows: CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 15 Sediment Trap 1 Sediment Trap 2 Area of Disturbance (Acres) 1.51 1.62 SSV Required per Acre of Disturbance 134 134 SSV Required = (CY) 202 217 Total Storage Provided = (CY) 675 308 Dry Storage Volume Required CY = 101 109 Dry Storage Volume Provided CY = 370 172 Wet Storage Volume Required CY = 101 109 Wet Storage Volume Provided CY = 305 136 5.0 Standard 4 - Post-Construction Operation and Maintenance The purpose of this standard is to ensure that long-term maintenance of the structural stormwater management systems is performed so they continue to function as designed and to implement operational source control and pollution prevention measures. Provisions for the post-construction operation and maintenance of the permanent stormwater management and pollution prevention devices are outlined on the plans and are as follows: 1. Pollution Prevention Team: The Owner shall be responsible for carrying out the provisions of the plan. 2. Sweeping: Parking lots, sidewalks, and other impervious surfaces shall be swept clean of sand and litter and any other pollutants at least twice per year a. Between November 15th and December 15th (after leaf fall) b. During April (after snow melt) 3. Outside Storage: Accessories or equipment stored outside shall be covered or maintained to minimize the possibility of these materials or their residue passing to stormwater. 4. Washing: No washing of vehicles, accessories, equipment, or appliances onsite. 5. Maintenance and Inspection of Stormwater Infrastructure: a. Monthly inspection of stormwater structures and outfalls. b. Clean sediment and debris from structures at least once per year during April. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 16 c. Comply with the hydrodynamic separator operations and maintenance requirements in accordance with the Operations and Maintenance Manual provided by the Manufacturer. d. Comply with the rain garden maintenance schedule. 6. Spills or Accidental Discharges: a. Comply with State and Federal regulations to contain and clean up any spill or discharge and dispose of materials at an approved facility. b. Contact Connecticut DEEP oil and chemical spill response division 860-424- 3338. c. The following steps should be performed as soon as possible - Stop the source of the spill - Contain the spill - Cover the spill with absorbent material such as kitty litter, saw dust, or oil absorbent pads. Do not use straw. - Dispose of absorber in accordance with Local and State regulations. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 17 The following is a general operations and maintenance schedule for the stormwater infrastructure and project site. MAINTENANCE SCHEDULE FOR STORMWATER BASINS Activity Schedule Prior to new spring growth reaching a height of 2” (e.g., shortly after forsythia or redbud blooms), trim any material standing from the previous year close to the ground (approximately 2”). Second growing season This will allow the soil to warm more quickly, which will stimulate the emergence and growth of native seedlings and reduce the likelihood of the meadow being invaded by shrubs. Problem weeds should be hand pulled or spot sprayed with an approved herbicide, such as Rodeo® or Garlon® 3A. If you did not plant vines or spiny plants as part of your mix, be vigilant about controlling them. These are more easily pulled when they are young rather than after they have had two to three months of growth. Examples include bindweed, blackberry, multiflora rose, mile-a-minute and Japanese hops. Be equally vigilant about controlling other invasive species, such as autumn olive and Japanese knotweed. Special Circumstances If you notice a heavy infestation of ragweed or foxtail in the second growing season, trim the meadow to a height of 8”. Trimming should cease by mid-September. For the basin and side slopes, inspect for invasive vegetation. Monthly Grassy weeds or persistent perennials can re-establish in these soils. Monitor and control weeds by hand pulling or spot spraying. Inspect for damage, undercut, or eroded area Semi-Annually Inspect Sediment Forebay and monitor for sediment accumulation. Remove any trash and organic debris (leaves) in spring & fall. Remove sediment from the sediment forebay or other pretreatment area when it accumulates to a depth of more than 12 inches or 50% of the design depth. Clean outlet of sediment forebay or other pretreatment measures when drawdown time exceeds 36 hours after the end of a storm event. Remove sediment from the infiltration basin surface when the sediment accumulation exceeds 2 inches or when drawdown time exceeds 48 hours after the end of a storm event, indicating that the system is clogged. Weed as necessary. Mow grass within infiltration basin to a height of 3 to 6 inches. Maintain a healthy, vigorous stand of grass cover; re-seed as necessary. Clean and remove debris & sediment from inlet and outlet structures. CLA Engineers, Inc. Civil · Structural · Survey December 16, 2024 Stormwater Management Report Proposed Trailer Storage Facility 375 Maple Ave. Montville 18 Mow side slopes. Close mowing throughout the regular growing season or extensive chemical use is not conducive to water quality improvement and wildlife habitat. Spring mowed vegetation can typically remain within basins providing cover for new emerging vegetation. Repair undercut or eroded areas. As needed maintenance Maintenance Schedule for Trailer Storage Areas Activity Schedule Sweep parking lots & impervious areas Between November 15th and December 15th (after leaf fall) During April (after snow melt) Remove and dispose of trash and debris onsite Daily - As needed maintenance Maintenance Schedule for Qualifying Pervious Area (QPA) Activity Schedule Sweep impervious areas Between November 15th and December 15th (after leaf fall) During April (after snow melt) Inspect QPA for erosion and loss of vegetation Annually - As needed maintenance Remove and dispose of trash and debris onsite Annually - As needed maintenance 24'±24'± EX WATERSHED #1 EX WATERSHED #2 ANALYSIS POINT # 2 ANALYSIS POINT # 1 WATERSHED BOUNDARY TIME OF CONCENTRATION FLOW PATH FLOOD ZONE AE REGULATORY FLOODWAY PROPERTY LINE LEGEND EXISTING WATERSHED 1 EXISTING WATERSHED 2 15 15 31 ANALYSIS POINT # 1 WATERSHED BOUNDARY TIME OF CONCENTRATION FLOW PATH FLOOD ZONE AE REGULATORY FLOODWAY PROPERTY LINE LEGEND PR WATERSHED 1a PR WATERSHED 1b PR WATERSHED 2a PR WATERSHED 2b PROPOSED WATERSHED 1a PROPOSED WATERSHED 1b PROPOSED WATERSHED 2a PROPOSED WATERSHED 2b STORMWATER BASIN 1 STORMWATER BASIN 2 ANALYSIS POINT # 2 QUALIFYING PERVIOUS AREA QUALIFYING PERVIOUS AREA CLA Engineers, Inc. Civil · Structural · Survey Appendix A NRCS Soil Report United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for State of Connecticut, Eastern Part 7767F Rand Whiney Natural Resources Conservation Service November 8, 2024 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 Soil Map..................................................................................................................5 Soil Map (7767F Rand Whitney)..........................................................................6 Legend..................................................................................................................7 Map Unit Legend (7767F Rand Whitney).............................................................8 Map Unit Descriptions (7767F Rand Whitney).....................................................8 State of Connecticut, Eastern Part..................................................................10 23A—Sudbury sandy loam, 0 to 5 percent slopes......................................10 34B—Merrimac fine sandy loam, 3 to 8 percent slopes..............................11 38C—Hinckley loamy sand, 3 to 15 percent slopes....................................13 75E—Hollis-Chatfield-Rock outcrop complex, 15 to 45 percent slopes......15 307—Urban land.........................................................................................18 W—Water....................................................................................................18 Soil Information for All Uses...............................................................................20 Soil Properties and Qualities..............................................................................20 Soil Qualities and Features.............................................................................20 Hydrologic Soil Group (7767F Rand Whitney)............................................20 References............................................................................................................25 4 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 5 6 Custom Soil Resource Report Soil Map (7767F Rand Whitney)459287045929604593050459314045932304593320459287045929604593050459314045932304593320738510 738600 738690 738780 738870 738960 739050 739140 739230 739320 738510 738600 738690 738780 738870 738960 739050 739140 739230 739320 41° 27' 22'' N 72° 8' 40'' W41° 27' 22'' N72° 8' 4'' W41° 27' 5'' N 72° 8' 40'' W41° 27' 5'' N 72° 8' 4'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 0 150 300 600 900 Feet 0 50 100 200 300 Meters Map Scale: 1:3,830 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:12,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: State of Connecticut, Eastern Part Survey Area Data: Version 2, Aug 30, 2024 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 14, 2022—Oct 6, 2022 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 7 Map Unit Legend (7767F Rand Whitney) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 23A Sudbury sandy loam, 0 to 5 percent slopes 1.4 5.3% 34B Merrimac fine sandy loam, 3 to 8 percent slopes 5.1 18.6% 38C Hinckley loamy sand, 3 to 15 percent slopes 0.5 1.8% 75E Hollis-Chatfield-Rock outcrop complex, 15 to 45 percent slopes 0.4 1.4% 307 Urban land 7.0 25.4% W Water 13.1 47.6% Totals for Area of Interest 27.5 100.0% Map Unit Descriptions (7767F Rand Whitney) The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not Custom Soil Resource Report 8 mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 9 State of Connecticut, Eastern Part 23A—Sudbury sandy loam, 0 to 5 percent slopes Map Unit Setting National map unit symbol: 9lkv Elevation: 0 to 1,200 feet Mean annual precipitation: 43 to 54 inches Mean annual air temperature: 45 to 55 degrees F Frost-free period: 140 to 185 days Farmland classification: All areas are prime farmland Map Unit Composition Sudbury and similar soils:80 percent Minor components:20 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Sudbury Setting Landform:Terraces, outwash plains Down-slope shape:Concave Across-slope shape:Linear Parent material:Sandy and gravelly glaciofluvial deposits derived from granite and/or schist and/or gneiss Typical profile Oe - 0 to 1 inches: moderately decomposed plant material A - 1 to 5 inches: sandy loam Bw1 - 5 to 17 inches: gravelly sandy loam Bw2 - 17 to 25 inches: sandy loam 2C - 25 to 60 inches: stratified gravel to sand Properties and qualities Slope:0 to 5 percent Depth to restrictive feature:More than 80 inches Drainage class:Moderately well drained Runoff class: Very low Capacity of the most limiting layer to transmit water (Ksat):High (1.98 to 5.95 in/hr) Depth to water table:About 17 to 36 inches Frequency of flooding:None Frequency of ponding:None Available water supply, 0 to 60 inches: Low (about 4.2 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2w Hydrologic Soil Group: A/D Ecological site: F144AY027MA - Moist Sandy Outwash Hydric soil rating: No Minor Components Agawam Percent of map unit:5 percent Custom Soil Resource Report 10 Landform:Terraces, outwash plains Down-slope shape:Linear Across-slope shape:Linear Hydric soil rating: No Merrimac Percent of map unit:5 percent Landform:Terraces, outwash plains, kames Down-slope shape:Linear Across-slope shape:Linear Hydric soil rating: No Ninigret Percent of map unit:5 percent Landform:Terraces, outwash plains Down-slope shape:Linear Across-slope shape:Concave Hydric soil rating: No Tisbury Percent of map unit:3 percent Landform:Terraces, outwash plains Down-slope shape:Concave Across-slope shape:Linear Hydric soil rating: No Walpole Percent of map unit:2 percent Landform:Drainageways on terraces, depressions on terraces Down-slope shape:Concave Across-slope shape:Concave Hydric soil rating: Yes 34B—Merrimac fine sandy loam, 3 to 8 percent slopes Map Unit Setting National map unit symbol: 2tyqs Elevation: 0 to 1,290 feet Mean annual precipitation: 36 to 71 inches Mean annual air temperature: 39 to 55 degrees F Frost-free period: 140 to 240 days Farmland classification: All areas are prime farmland Map Unit Composition Merrimac and similar soils:86 percent Minor components:14 percent Estimates are based on observations, descriptions, and transects of the mapunit. Custom Soil Resource Report 11 Description of Merrimac Setting Landform:Outwash plains, outwash terraces, moraines, eskers, kames Landform position (two-dimensional):Backslope, footslope, summit, shoulder Landform position (three-dimensional):Side slope, crest, riser, tread Down-slope shape:Convex Across-slope shape:Convex Parent material:Loamy glaciofluvial deposits derived from granite, schist, and gneiss over sandy and gravelly glaciofluvial deposits derived from granite, schist, and gneiss Typical profile Ap - 0 to 10 inches: fine sandy loam Bw1 - 10 to 22 inches: fine sandy loam Bw2 - 22 to 26 inches: stratified gravel to gravelly loamy sand 2C - 26 to 65 inches: stratified gravel to very gravelly sand Properties and qualities Slope:3 to 8 percent Depth to restrictive feature:More than 80 inches Drainage class:Somewhat excessively drained Runoff class: Very low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to very high (1.42 to 99.90 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:2 percent Maximum salinity:Nonsaline (0.0 to 1.4 mmhos/cm) Sodium adsorption ratio, maximum:1.0 Available water supply, 0 to 60 inches: Low (about 4.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2s Hydrologic Soil Group: A Ecological site: F145XY008MA - Dry Outwash Hydric soil rating: No Minor Components Sudbury Percent of map unit:5 percent Landform:Deltas, terraces, outwash plains Landform position (two-dimensional):Footslope Landform position (three-dimensional):Tread, dip Down-slope shape:Concave Across-slope shape:Linear Hydric soil rating: No Hinckley Percent of map unit:5 percent Landform:Deltas, kames, eskers, outwash plains Landform position (two-dimensional):Summit, shoulder, backslope Custom Soil Resource Report 12 Landform position (three-dimensional):Nose slope, side slope, crest, head slope, rise Down-slope shape:Convex Across-slope shape:Convex, linear Hydric soil rating: No Windsor Percent of map unit:3 percent Landform:Dunes, deltas, outwash terraces, outwash plains Landform position (two-dimensional):Summit Landform position (three-dimensional):Tread, riser Down-slope shape:Convex, linear Across-slope shape:Convex, linear Hydric soil rating: No Walpole Percent of map unit:1 percent Landform:Depressions Landform position (three-dimensional):Tread Down-slope shape:Concave Across-slope shape:Concave Ecological site:F144AY028MA - Wet Outwash Hydric soil rating: Yes 38C—Hinckley loamy sand, 3 to 15 percent slopes Map Unit Setting National map unit symbol: 2svmb Elevation: 0 to 1,290 feet Mean annual precipitation: 36 to 71 inches Mean annual air temperature: 39 to 55 degrees F Frost-free period: 140 to 240 days Farmland classification: Farmland of statewide importance Map Unit Composition Hinckley and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Hinckley Setting Landform:Outwash deltas, outwash terraces, moraines, eskers, kames, outwash plains, kame terraces Landform position (two-dimensional):Shoulder, backslope, footslope, toeslope, summit Landform position (three-dimensional):Nose slope, side slope, crest, head slope, riser, tread Down-slope shape:Concave, convex, linear Across-slope shape:Convex, linear, concave Custom Soil Resource Report 13 Parent material:Sandy and gravelly glaciofluvial deposits derived from gneiss and/or granite and/or schist Typical profile Oe - 0 to 1 inches: moderately decomposed plant material A - 1 to 8 inches: loamy sand Bw1 - 8 to 11 inches: gravelly loamy sand Bw2 - 11 to 16 inches: gravelly loamy sand BC - 16 to 19 inches: very gravelly loamy sand C - 19 to 65 inches: very gravelly sand Properties and qualities Slope:3 to 15 percent Depth to restrictive feature:More than 80 inches Drainage class:Excessively drained Runoff class: Very low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to very high (1.42 to 99.90 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Maximum salinity:Nonsaline (0.0 to 1.9 mmhos/cm) Available water supply, 0 to 60 inches: Low (about 3.1 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4e Hydrologic Soil Group: A Ecological site: F144AY022MA - Dry Outwash Hydric soil rating: No Minor Components Merrimac Percent of map unit:5 percent Landform:Kames, outwash plains, outwash terraces, moraines, eskers Landform position (two-dimensional):Backslope, footslope, shoulder, toeslope, summit Landform position (three-dimensional):Side slope, crest, head slope, nose slope, riser, tread Down-slope shape:Convex Across-slope shape:Convex Hydric soil rating: No Windsor Percent of map unit:5 percent Landform:Moraines, eskers, kames, outwash deltas, outwash terraces, outwash plains, kame terraces Landform position (two-dimensional):Shoulder, backslope, footslope, toeslope, summit Landform position (three-dimensional):Nose slope, side slope, crest, head slope, riser, tread Down-slope shape:Concave, convex, linear Across-slope shape:Convex, linear, concave Hydric soil rating: No Custom Soil Resource Report 14 Agawam Percent of map unit:3 percent Landform:Outwash deltas, outwash terraces, moraines, eskers, kames, outwash plains, kame terraces Landform position (two-dimensional):Shoulder, backslope, toeslope, summit, footslope Landform position (three-dimensional):Nose slope, side slope, crest, head slope, riser, tread Down-slope shape:Concave, convex, linear Across-slope shape:Convex, linear, concave Hydric soil rating: No Sudbury Percent of map unit:2 percent Landform:Outwash deltas, moraines, outwash plains, kame terraces, outwash terraces Landform position (two-dimensional):Backslope, footslope Landform position (three-dimensional):Base slope, tread Down-slope shape:Concave, linear Across-slope shape:Concave, linear Hydric soil rating: No 75E—Hollis-Chatfield-Rock outcrop complex, 15 to 45 percent slopes Map Unit Setting National map unit symbol: 9lqp Elevation: 0 to 1,200 feet Mean annual precipitation: 43 to 56 inches Mean annual air temperature: 45 to 55 degrees F Frost-free period: 140 to 185 days Farmland classification: Not prime farmland Map Unit Composition Hollis and similar soils:35 percent Chatfield and similar soils:30 percent Rock outcrop:15 percent Minor components:20 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Hollis Setting Landform:Ridges, hills Down-slope shape:Convex Across-slope shape:Convex Parent material:Loamy melt-out till derived from granite and/or schist and/or gneiss Typical profile Oa - 0 to 1 inches: highly decomposed plant material Custom Soil Resource Report 15 A - 1 to 6 inches: gravelly fine sandy loam Bw1 - 6 to 9 inches: channery fine sandy loam Bw2 - 9 to 15 inches: gravelly fine sandy loam 2R - 15 to 80 inches: bedrock Properties and qualities Slope:15 to 45 percent Surface area covered with cobbles, stones or boulders:9.0 percent Depth to restrictive feature:10 to 20 inches to lithic bedrock Drainage class:Somewhat excessively drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat):Low to high (0.01 to 5.95 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Available water supply, 0 to 60 inches: Very low (about 1.8 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7s Hydrologic Soil Group: D Ecological site: F144AY033MA - Shallow Dry Till Uplands Hydric soil rating: No Description of Chatfield Setting Landform:Ridges, hills Down-slope shape:Convex Across-slope shape:Linear Parent material:Coarse-loamy melt-out till derived from granite and/or schist and/or gneiss Typical profile Oa - 0 to 1 inches: highly decomposed plant material A - 1 to 6 inches: gravelly fine sandy loam Bw1 - 6 to 15 inches: gravelly fine sandy loam Bw2 - 15 to 29 inches: gravelly fine sandy loam 2R - 29 to 80 inches: unweathered bedrock Properties and qualities Slope:15 to 45 percent Surface area covered with cobbles, stones or boulders:1.6 percent Depth to restrictive feature:20 to 40 inches to lithic bedrock Drainage class:Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat):Low to high (0.01 to 5.95 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Available water supply, 0 to 60 inches: Low (about 3.3 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7s Custom Soil Resource Report 16 Hydrologic Soil Group: B Ecological site: F144AY034CT - Well Drained Till Uplands Hydric soil rating: No Description of Rock Outcrop Typical profile R - 0 to 0 inches: bedrock Properties and qualities Slope:15 to 45 percent Depth to restrictive feature:0 inches to lithic bedrock Runoff class: Very high Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8 Hydrologic Soil Group: D Hydric soil rating: Unranked Minor Components Charlton Percent of map unit:7 percent Landform:Hills Down-slope shape:Linear Across-slope shape:Linear Hydric soil rating: No Leicester Percent of map unit:5 percent Landform:Drainageways, depressions Down-slope shape:Linear Across-slope shape:Concave Hydric soil rating: Yes Sutton, very stony Percent of map unit:5 percent Landform:Drainageways, depressions Down-slope shape:Concave Across-slope shape:Linear Hydric soil rating: No Unnamed, red parent material Percent of map unit:1 percent Hydric soil rating: No Unnamed, sandy subsoil Percent of map unit:1 percent Hydric soil rating: No Brimfield Percent of map unit:1 percent Landform:Ridges, hills Down-slope shape:Convex Across-slope shape:Convex Hydric soil rating: No Custom Soil Resource Report 17 307—Urban land Map Unit Setting National map unit symbol: 9lmh Elevation: 0 to 2,000 feet Mean annual precipitation: 43 to 56 inches Mean annual air temperature: 45 to 55 degrees F Frost-free period: 120 to 185 days Farmland classification: Not prime farmland Map Unit Composition Urban land:80 percent Minor components:20 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Urban Land Typical profile H - 0 to 6 inches: material Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8 Hydrologic Soil Group: D Hydric soil rating: Unranked Minor Components Unnamed, undisturbed soils Percent of map unit:10 percent Hydric soil rating: No Udorthents, wet substratum Percent of map unit:10 percent Down-slope shape:Convex Across-slope shape:Linear Hydric soil rating: No W—Water Map Unit Composition Water:100 percent Custom Soil Resource Report 18 Estimates are based on observations, descriptions, and transects of the mapunit. Custom Soil Resource Report 19 Soil Information for All Uses Soil Properties and Qualities The Soil Properties and Qualities section includes various soil properties and qualities displayed as thematic maps with a summary table for the soil map units in the selected area of interest. A single value or rating for each map unit is generated by aggregating the interpretive ratings of individual map unit components. This aggregation process is defined for each property or quality. Soil Qualities and Features Soil qualities are behavior and performance attributes that are not directly measured, but are inferred from observations of dynamic conditions and from soil properties. Example soil qualities include natural drainage, and frost action. Soil features are attributes that are not directly part of the soil. Example soil features include slope and depth to restrictive layer. These features can greatly impact the use and management of the soil. Hydrologic Soil Group (7767F Rand Whitney) Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. 20 Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Custom Soil Resource Report 21 22 Custom Soil Resource Report Map—Hydrologic Soil Group (7767F Rand Whitney)459287045929604593050459314045932304593320459287045929604593050459314045932304593320738510 738600 738690 738780 738870 738960 739050 739140 739230 739320 738510 738600 738690 738780 738870 738960 739050 739140 739230 739320 41° 27' 22'' N 72° 8' 40'' W41° 27' 22'' N72° 8' 4'' W41° 27' 5'' N 72° 8' 40'' W41° 27' 5'' N 72° 8' 4'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 0 150 300 600 900 Feet 0 50 100 200 300 Meters Map Scale: 1:3,830 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:12,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: State of Connecticut, Eastern Part Survey Area Data: Version 2, Aug 30, 2024 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 14, 2022—Oct 6, 2022 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 23 Table—Hydrologic Soil Group (7767F Rand Whitney) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 23A Sudbury sandy loam, 0 to 5 percent slopes A/D 1.4 5.3% 34B Merrimac fine sandy loam, 3 to 8 percent slopes A 5.1 18.6% 38C Hinckley loamy sand, 3 to 15 percent slopes A 0.5 1.8% 75E Hollis-Chatfield-Rock outcrop complex, 15 to 45 percent slopes D 0.4 1.4% 307 Urban land D 7.0 25.4% W Water 13.1 47.6% Totals for Area of Interest 27.5 100.0% Rating Options—Hydrologic Soil Group (7767F Rand Whitney) Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Custom Soil Resource Report 24 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 25 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 26 CLA Engineers, Inc. Civil · Structural · Survey Appendix B Hydrograph Reports – 2, 10 & 100-Year Frequencies 1 - Ex Watershed 1 2 - Ex Watershed 2 3 - Existing Conditions 4 - Pr Watershed 1a 5 - Basin 1 6 - Pr Watershed 1b 7 - Pr Watershed 1 8 - Pr Watershed 2a 9 - Basin 2 10 - Pr Watershed 2b 11 - Pr Watershed 2 12 - Proposed Conditions 1 Watershed Model Schematic Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Project: Analysis.gpw Wednesday, 12 / 11 / 2024 Hyd.Origin Description Legend 1 SCS Runoff Ex Watershed 1 2 SCS Runoff Ex Watershed 2 3 Combine Existing Conditions 4 SCS Runoff Pr Watershed 1a 5 Reservoir Basin 1 6 SCS Runoff Pr Watershed 1b 7 Combine Pr Watershed 1 8 SCS Runoff Pr Watershed 2a 9 Reservoir Basin 2 10 SCS Runoff Pr Watershed 2b 11 Combine Pr Watershed 2 12 Combine Proposed Conditions Hydraflow Table of Contents Analysis.gpw Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Watershed Model Schematic...................................................................................... 1 Hydrograph Return Period Recap............................................................................. 2 2 - Year Summary Report......................................................................................................................... 3 Hydrograph Reports................................................................................................................... 4 Hydrograph No. 1, SCS Runoff, Ex Watershed 1..................................................................... 4 TR-55 Tc Worksheet............................................................................................................ 5 Precipitation Report............................................................................................................. 6 Hydrograph No. 2, SCS Runoff, Ex Watershed 2..................................................................... 7 TR-55 Tc Worksheet............................................................................................................ 8 Precipitation Report............................................................................................................. 9 Hydrograph No. 3, Combine, Existing Conditions.................................................................. 10 Hydrograph No. 4, SCS Runoff, Pr Watershed 1a................................................................. 11 TR-55 Tc Worksheet.......................................................................................................... 12 Precipitation Report...........................................................................................................13 Hydrograph No. 5, Reservoir, Basin 1.................................................................................... 14 Pond Report - Pond 1........................................................................................................ 15 Hydrograph No. 6, SCS Runoff, Pr Watershed 1b................................................................. 16 Precipitation Report...........................................................................................................17 Hydrograph No. 7, Combine, Pr Watershed 1........................................................................ 18 Hydrograph No. 8, SCS Runoff, Pr Watershed 2a................................................................. 19 TR-55 Tc Worksheet.......................................................................................................... 20 Precipitation Report...........................................................................................................21 Hydrograph No. 9, Reservoir, Basin 2.................................................................................... 22 Pond Report - Pond 2........................................................................................................ 23 Hydrograph No. 10, SCS Runoff, Pr Watershed 2b............................................................... 24 Precipitation Report...........................................................................................................25 Hydrograph No. 11, Combine, Pr Watershed 2...................................................................... 26 Hydrograph No. 12, Combine, Proposed Conditions............................................................. 27 10 - Year Summary Report....................................................................................................................... 28 Hydrograph Reports................................................................................................................. 29 Hydrograph No. 1, SCS Runoff, Ex Watershed 1................................................................... 29 Precipitation Report...........................................................................................................30 Hydrograph No. 2, SCS Runoff, Ex Watershed 2................................................................... 31 Precipitation Report...........................................................................................................32 Hydrograph No. 3, Combine, Existing Conditions.................................................................. 33 Hydrograph No. 4, SCS Runoff, Pr Watershed 1a................................................................. 34 Precipitation Report...........................................................................................................35 Hydrograph No. 5, Reservoir, Basin 1.................................................................................... 36 Hydrograph No. 6, SCS Runoff, Pr Watershed 1b................................................................. 37 Precipitation Report...........................................................................................................38 Hydrograph No. 7, Combine, Pr Watershed 1........................................................................ 39 Hydrograph No. 8, SCS Runoff, Pr Watershed 2a................................................................. 40 Precipitation Report...........................................................................................................41 Contents continued...Analysis.gpw Hydrograph No. 9, Reservoir, Basin 2.................................................................................... 42 Hydrograph No. 10, SCS Runoff, Pr Watershed 2b............................................................... 43 Precipitation Report...........................................................................................................44 Hydrograph No. 11, Combine, Pr Watershed 2...................................................................... 45 Hydrograph No. 12, Combine, Proposed Conditions............................................................. 46 25 - Year Summary Report....................................................................................................................... 47 Hydrograph Reports................................................................................................................. 48 Hydrograph No. 1, SCS Runoff, Ex Watershed 1................................................................... 48 Precipitation Report...........................................................................................................49 Hydrograph No. 2, SCS Runoff, Ex Watershed 2................................................................... 50 Precipitation Report...........................................................................................................51 Hydrograph No. 3, Combine, Existing Conditions.................................................................. 52 Hydrograph No. 4, SCS Runoff, Pr Watershed 1a................................................................. 53 Precipitation Report...........................................................................................................54 Hydrograph No. 5, Reservoir, Basin 1.................................................................................... 55 Hydrograph No. 6, SCS Runoff, Pr Watershed 1b................................................................. 56 Precipitation Report...........................................................................................................57 Hydrograph No. 7, Combine, Pr Watershed 1........................................................................ 58 Hydrograph No. 8, SCS Runoff, Pr Watershed 2a................................................................. 59 Precipitation Report...........................................................................................................60 Hydrograph No. 9, Reservoir, Basin 2.................................................................................... 61 Hydrograph No. 10, SCS Runoff, Pr Watershed 2b............................................................... 62 Precipitation Report...........................................................................................................63 Hydrograph No. 11, Combine, Pr Watershed 2...................................................................... 64 Hydrograph No. 12, Combine, Proposed Conditions............................................................. 65 50 - Year Summary Report....................................................................................................................... 66 Hydrograph Reports................................................................................................................. 67 Hydrograph No. 1, SCS Runoff, Ex Watershed 1................................................................... 67 Precipitation Report...........................................................................................................68 Hydrograph No. 2, SCS Runoff, Ex Watershed 2................................................................... 69 Precipitation Report...........................................................................................................70 Hydrograph No. 3, Combine, Existing Conditions.................................................................. 71 Hydrograph No. 4, SCS Runoff, Pr Watershed 1a................................................................. 72 Precipitation Report...........................................................................................................73 Hydrograph No. 5, Reservoir, Basin 1.................................................................................... 74 Hydrograph No. 6, SCS Runoff, Pr Watershed 1b................................................................. 75 Precipitation Report...........................................................................................................76 Hydrograph No. 7, Combine, Pr Watershed 1........................................................................ 77 Hydrograph No. 8, SCS Runoff, Pr Watershed 2a................................................................. 78 Precipitation Report...........................................................................................................79 Hydrograph No. 9, Reservoir, Basin 2.................................................................................... 80 Hydrograph No. 10, SCS Runoff, Pr Watershed 2b............................................................... 81 Precipitation Report...........................................................................................................82 Hydrograph No. 11, Combine, Pr Watershed 2...................................................................... 83 Hydrograph No. 12, Combine, Proposed Conditions............................................................. 84 100 - Year Contents continued...Analysis.gpw Summary Report....................................................................................................................... 85 Hydrograph Reports................................................................................................................. 86 Hydrograph No. 1, SCS Runoff, Ex Watershed 1................................................................... 86 Precipitation Report...........................................................................................................87 Hydrograph No. 2, SCS Runoff, Ex Watershed 2................................................................... 88 Precipitation Report...........................................................................................................89 Hydrograph No. 3, Combine, Existing Conditions.................................................................. 90 Hydrograph No. 4, SCS Runoff, Pr Watershed 1a................................................................. 91 Precipitation Report...........................................................................................................92 Hydrograph No. 5, Reservoir, Basin 1.................................................................................... 93 Hydrograph No. 6, SCS Runoff, Pr Watershed 1b................................................................. 94 Precipitation Report...........................................................................................................95 Hydrograph No. 7, Combine, Pr Watershed 1........................................................................ 96 Hydrograph No. 8, SCS Runoff, Pr Watershed 2a................................................................. 97 Precipitation Report...........................................................................................................98 Hydrograph No. 9, Reservoir, Basin 2.................................................................................... 99 Hydrograph No. 10, SCS Runoff, Pr Watershed 2b............................................................. 100 Precipitation Report......................................................................................................... 101 Hydrograph No. 11, Combine, Pr Watershed 2.................................................................... 102 Hydrograph No. 12, Combine, Proposed Conditions........................................................... 103 Hydrograph Return Period Recap 2 Hyd. Hydrograph Inflow Peak Outflow (cfs) Hydrograph No. type hyd(s)Description (origin) 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr 1 SCS Runoff ------ ------- 0.009 ------- ------- 0.227 0.723 1.220 1.814 Ex Watershed 1 2 SCS Runoff ------ ------- 0.008 ------- ------- 0.172 0.629 1.235 2.083 Ex Watershed 2 3 Combine 1, 2 ------- 0.016 ------- ------- 0.317 1.093 2.097 3.427 Existing Conditions 4 SCS Runoff ------ ------- 2.493 ------- ------- 5.133 6.888 8.233 9.663 Pr Watershed 1a 5 Reservoir 4 ------- 0.000 ------- ------- 0.119 0.393 0.874 1.677 Basin 1 6 SCS Runoff ------ ------- 0.000 ------- ------- 0.008 0.038 0.102 0.186 Pr Watershed 1b 7 Combine 5, 6 ------- 0.000 ------- ------- 0.122 0.402 0.896 1.722 Pr Watershed 1 8 SCS Runoff ------ ------- 0.893 ------- ------- 1.907 2.590 3.115 3.675 Pr Watershed 2a 9 Reservoir 8 ------- 0.000 ------- ------- 0.050 0.183 0.428 0.830 Basin 2 10 SCS Runoff ------ ------- 0.044 ------- ------- 0.746 1.554 2.246 3.040 Pr Watershed 2b 11 Combine 9, 10 ------- 0.044 ------- ------- 0.746 1.554 2.246 3.040 Pr Watershed 2 12 Combine 7, 11 ------- 0.044 ------- ------- 0.746 1.591 2.343 3.224 Proposed Conditions Proj. file: Analysis.gpw Wednesday, 12 / 11 / 2024 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hydrograph Summary Report 3 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 SCS Runoff 0.009 1 972 319 ------ ------ ------ Ex Watershed 1 2 SCS Runoff 0.008 1 1390 168 ------ ------ ------ Ex Watershed 2 3 Combine 0.016 1 1384 487 1, 2 ------ ------ Existing Conditions 4 SCS Runoff 2.493 1 732 10,344 ------ ------ ------ Pr Watershed 1a 5 Reservoir 0.000 1 n/a 0 4 232.45 10,344 Basin 1 6 SCS Runoff 0.000 1 1424 5 ------ ------ ------ Pr Watershed 1b 7 Combine 0.000 1 1424 5 5, 6 ------ ------ Pr Watershed 1 8 SCS Runoff 0.893 1 729 3,204 ------ ------ ------ Pr Watershed 2a 9 Reservoir 0.000 1 n/a 0 8 232.56 3,204 Basin 2 10 SCS Runoff 0.044 1 773 912 ------ ------ ------ Pr Watershed 2b 11 Combine 0.044 1 773 912 9, 10 ------ ------ Pr Watershed 2 12 Combine 0.044 1 773 917 7, 11 ------ ------ Proposed Conditions Analysis.gpw Return Period: 2 Year Wednesday, 12 / 11 / 2024 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Hydrograph type = SCS Runoff Peak discharge = 0.009 cfs Storm frequency = 2 yrs Time to peak = 972 min Time interval = 1 min Hyd. volume = 319 cuft Drainage area = 1.440 ac Curve number = 44* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 10.30 min Total precip. = 3.45 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.620 x 36) + (0.790 x 49) + (0.030 x 98)] / 1.440 4 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Ex Watershed 1 Hyd. No. 1 -- 2 Year Hyd No. 1 TR55 Tc Worksheet 5 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hyd. No. 1 Ex Watershed 1 Description A B C Totals Sheet Flow Manning's n-value = 0.240 0.011 0.011 Flow length (ft) = 40.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.45 0.00 0.00 Land slope (%) = 1.10 0.00 0.00 Travel Time (min) = 8.39 + 0.00 + 0.00 = 8.39 Shallow Concentrated Flow Flow length (ft) = 65.00 74.00 43.00 Watercourse slope (%) = 12.70 5.00 0.10 Surface description = Unpaved Unpaved Unpaved Average velocity (ft/s) =5.75 3.61 0.51 Travel Time (min) = 0.19 + 0.34 + 1.40 = 1.93 Channel Flow X sectional flow area (sqft) = 0.00 0.00 0.00 Wetted perimeter (ft) = 0.00 0.00 0.00 Channel slope (%) = 0.00 0.00 0.00 Manning's n-value = 0.015 0.015 0.015 Velocity (ft/s) =0.00 0.00 0.00 Flow length (ft) ({0})0.0 0.0 0.0 Travel Time (min) = 0.00 + 0.00 + 0.00 = 0.00 Total Travel Time, Tc .............................................................................. 10.30 min Precipitation Report 6 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Storm Frequency = 2 yrs Time interval = 1 min Total precip. = 3.4500 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 1 : Ex Watershed 1 - 2 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Hydrograph type = SCS Runoff Peak discharge = 0.008 cfs Storm frequency = 2 yrs Time to peak = 1390 min Time interval = 1 min Hyd. volume = 168 cuft Drainage area = 3.500 ac Curve number = 40* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 20.40 min Total precip. = 3.45 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(2.870 x 36) + (0.540 x 49) + (0.090 x 98)] / 3.500 7 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Ex Watershed 2 Hyd. No. 2 -- 2 Year Hyd No. 2 TR55 Tc Worksheet 8 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hyd. No. 2 Ex Watershed 2 Description A B C Totals Sheet Flow Manning's n-value = 0.240 0.011 0.011 Flow length (ft) = 138.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.45 0.00 0.00 Land slope (%) = 2.40 0.00 0.00 Travel Time (min) = 16.53 + 0.00 + 0.00 = 16.53 Shallow Concentrated Flow Flow length (ft) = 80.00 200.00 181.00 Watercourse slope (%) = 6.00 2.40 1.90 Surface description = Unpaved Unpaved Unpaved Average velocity (ft/s) =3.95 2.50 2.22 Travel Time (min) = 0.34 + 1.33 + 1.36 = 3.03 Channel Flow X sectional flow area (sqft) = 13.00 0.00 0.00 Wetted perimeter (ft) = 15.00 0.00 0.00 Channel slope (%) = 3.10 0.00 0.00 Manning's n-value = 0.040 0.015 0.015 Velocity (ft/s) =5.96 0.00 0.00 Flow length (ft) ({0})311.0 0.0 0.0 Travel Time (min) = 0.87 + 0.00 + 0.00 = 0.87 Total Travel Time, Tc .............................................................................. 20.40 min Precipitation Report 9 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Storm Frequency = 2 yrs Time interval = 1 min Total precip. = 3.4500 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 2 : Ex Watershed 2 - 2 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 3 Existing Conditions Hydrograph type = Combine Peak discharge = 0.016 cfs Storm frequency = 2 yrs Time to peak = 1384 min Time interval = 1 min Hyd. volume = 487 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 4.940 ac 10 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Existing Conditions Hyd. No. 3 -- 2 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Hydrograph type = SCS Runoff Peak discharge = 2.493 cfs Storm frequency = 2 yrs Time to peak = 732 min Time interval = 1 min Hyd. volume = 10,344 cuft Drainage area = 2.250 ac Curve number = 75* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 14.50 min Total precip. = 3.45 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.860 x 39) + (1.390 x 98)] / 2.250 11 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Pr Watershed 1a Hyd. No. 4 -- 2 Year Hyd No. 4 TR55 Tc Worksheet 12 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hyd. No. 4 Pr Watershed 1a Description A B C Totals Sheet Flow Manning's n-value = 0.011 0.011 0.011 Flow length (ft) = 151.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.45 0.00 0.00 Land slope (%) = 3.70 0.00 0.00 Travel Time (min) = 1.27 + 0.00 + 0.00 = 1.27 Shallow Concentrated Flow Flow length (ft) = 0.00 0.00 0.00 Watercourse slope (%) = 0.00 0.00 0.00 Surface description = Paved Paved Paved Average velocity (ft/s) =0.00 0.00 0.00 Travel Time (min) = 0.00 + 0.00 + 0.00 = 0.00 Channel Flow X sectional flow area (sqft) = 5.00 0.00 0.00 Wetted perimeter (ft) = 8.00 0.00 0.00 Channel slope (%) = 0.40 0.00 0.00 Manning's n-value = 0.400 0.015 0.015 Velocity (ft/s) =0.17 0.00 0.00 Flow length (ft) ({0})136.0 0.0 0.0 Travel Time (min) = 13.18 + 0.00 + 0.00 = 13.18 Total Travel Time, Tc .............................................................................. 14.50 min Precipitation Report 13 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Storm Frequency = 2 yrs Time interval = 1 min Total precip. = 3.4500 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 4 : Pr Watershed 1a - 2 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 5 Basin 1 Hydrograph type = Reservoir Peak discharge = 0.000 cfs Storm frequency = 2 yrs Time to peak = n/a Time interval = 1 min Hyd. volume = 0 cuft Inflow hyd. No. = 4 - Pr Watershed 1a Max. Elevation = 232.45 ft Reservoir name = Pond 1 Max. Storage = 10,344 cuft Storage Indication method used. 14 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Basin 1 Hyd. No. 5 -- 2 Year Hyd No. 5 Hyd No. 4 Total storage used = 10,344 cuft Pond Report 15 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Pond No. 1 - Pond 1 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 231.00 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft) 0.00 231.00 5,574 0 0 2.00 233.00 8,849 14,296 14,296 2.50 233.50 9,711 4,638 18,934 3.00 234.00 10,591 5,073 24,007 4.00 235.00 12,615 11,587 35,594 Culvert / Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise (in)= 0.00 0.00 0.00 0.00 Span (in)= 0.00 0.00 0.00 0.00 No. Barrels = 0 000 Invert El. (ft)= 0.00 0.00 0.00 0.00 Length (ft)= 0.00 0.00 0.00 0.00 Slope (%)= 0.00 0.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff.= 0.60 0.60 0.60 0.60 Multi-Stage = n/a NoNoNo Crest Len (ft)= 4.00 0.00 0.00 0.00 Crest El. (ft)= 233.50 0.00 0.00 0.00 Weir Coeff.= 3.33 3.33 3.33 3.33 Weir Type = Rect --- --- --- Multi-Stage = No No No No Exfil.(in/hr)= 0.000 (by Wet area) TW Elev. (ft)= 0.00 Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s). Stage / Storage / Discharge Table Stage Storage Elevation Clv A Clv B Clv C PrfRsr Wr A Wr B Wr C Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 231.00 --- --- --- --- 0.00 --- --- --- --- --- 0.000 2.00 14,296 233.00 --- --- --- --- 0.00 --- --- --- --- --- 0.000 2.50 18,934 233.50 --- --- --- --- 0.00 --- --- --- --- --- 0.000 3.00 24,007 234.00 --- --- --- --- 4.71 --- --- --- --- --- 4.709 4.00 35,594 235.00 --- --- --- --- 24.47 --- --- --- --- --- 24.47 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Hydrograph type = SCS Runoff Peak discharge = 0.000 cfs Storm frequency = 2 yrs Time to peak = 1424 min Time interval = 1 min Hyd. volume = 5 cuft Drainage area = 0.210 ac Curve number = 39* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 3.45 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.210 x 39)] / 0.210 16 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Pr Watershed 1b Hyd. No. 6 -- 2 Year Hyd No. 6 Precipitation Report 17 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Storm Frequency = 2 yrs Time interval = 1 min Total precip. = 3.4500 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 6 : Pr Watershed 1b - 2 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 7 Pr Watershed 1 Hydrograph type = Combine Peak discharge = 0.000 cfs Storm frequency = 2 yrs Time to peak = 1424 min Time interval = 1 min Hyd. volume = 5 cuft Inflow hyds. = 5, 6 Contrib. drain. area = 0.210 ac 18 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Pr Watershed 1 Hyd. No. 7 -- 2 Year Hyd No. 7 Hyd No. 5 Hyd No. 6 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Hydrograph type = SCS Runoff Peak discharge = 0.893 cfs Storm frequency = 2 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 3,204 cuft Drainage area = 0.770 ac Curve number = 73* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 8.80 min Total precip. = 3.45 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.320 x 39) + (0.450 x 98)] / 0.770 19 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Pr Watershed 2a Hyd. No. 8 -- 2 Year Hyd No. 8 TR55 Tc Worksheet 20 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hyd. No. 8 Pr Watershed 2a Description A B C Totals Sheet Flow Manning's n-value = 0.011 0.011 0.011 Flow length (ft) = 132.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.45 0.00 0.00 Land slope (%) = 3.00 0.00 0.00 Travel Time (min) = 1.24 + 0.00 + 0.00 = 1.24 Shallow Concentrated Flow Flow length (ft) = 0.00 0.00 0.00 Watercourse slope (%) = 0.00 0.00 0.00 Surface description = Paved Paved Paved Average velocity (ft/s) =0.00 0.00 0.00 Travel Time (min) = 0.00 + 0.00 + 0.00 = 0.00 Channel Flow X sectional flow area (sqft) = 5.00 5.00 0.00 Wetted perimeter (ft) = 8.00 8.00 0.00 Channel slope (%) = 2.80 1.30 0.00 Manning's n-value = 0.400 0.400 0.015 Velocity (ft/s) =0.45 0.31 0.00 Flow length (ft) ({0})120.0 58.0 0.0 Travel Time (min) = 4.40 + 3.12 + 0.00 = 7.51 Total Travel Time, Tc .............................................................................. 8.80 min Precipitation Report 21 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Storm Frequency = 2 yrs Time interval = 1 min Total precip. = 3.4500 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 8 : Pr Watershed 2a - 2 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 9 Basin 2 Hydrograph type = Reservoir Peak discharge = 0.000 cfs Storm frequency = 2 yrs Time to peak = n/a Time interval = 1 min Hyd. volume = 0 cuft Inflow hyd. No. = 8 - Pr Watershed 2a Max. Elevation = 232.56 ft Reservoir name = Pond 2 Max. Storage = 3,204 cuft Storage Indication method used. 22 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Basin 2 Hyd. No. 9 -- 2 Year Hyd No. 9 Hyd No. 8 Total storage used = 3,204 cuft Pond Report 23 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Pond No. 2 - Pond 2 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 231.00 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft) 0.00 231.00 1,370 0 0 2.00 233.00 2,814 4,098 4,098 2.50 233.50 3,215 1,506 5,604 3.00 234.00 3,632 1,711 7,314 4.00 235.00 4,656 4,133 11,447 Culvert / Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise (in)= 0.00 0.00 0.00 0.00 Span (in)= 0.00 0.00 0.00 0.00 No. Barrels = 0 000 Invert El. (ft)= 0.00 0.00 0.00 0.00 Length (ft)= 0.00 0.00 0.00 0.00 Slope (%)= 0.00 0.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff.= 0.60 0.60 0.60 0.60 Multi-Stage = n/a NoNoNo Crest Len (ft)= 3.00 0.00 0.00 0.00 Crest El. (ft)= 233.50 0.00 0.00 0.00 Weir Coeff.= 3.33 3.33 3.33 3.33 Weir Type = Rect --- --- --- Multi-Stage = No No No No Exfil.(in/hr)= 0.000 (by Wet area) TW Elev. (ft)= 0.00 Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s). Stage / Storage / Discharge Table Stage Storage Elevation Clv A Clv B Clv C PrfRsr Wr A Wr B Wr C Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 231.00 --- --- --- --- 0.00 --- --- --- --- --- 0.000 2.00 4,098 233.00 --- --- --- --- 0.00 --- --- --- --- --- 0.000 2.50 5,604 233.50 --- --- --- --- 0.00 --- --- --- --- --- 0.000 3.00 7,314 234.00 --- --- --- --- 3.53 --- --- --- --- --- 3.532 4.00 11,447 235.00 --- --- --- --- 18.35 --- --- --- --- --- 18.35 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Hydrograph type = SCS Runoff Peak discharge = 0.044 cfs Storm frequency = 2 yrs Time to peak = 773 min Time interval = 1 min Hyd. volume = 912 cuft Drainage area = 1.580 ac Curve number = 49* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 10.00 min Total precip. = 3.45 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.650 x 36) + (0.640 x 39) + (0.290 x 98)] / 1.580 24 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Pr Watershed 2b Hyd. No. 10 -- 2 Year Hyd No. 10 Precipitation Report 25 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Storm Frequency = 2 yrs Time interval = 1 min Total precip. = 3.4500 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 10 : Pr Watershed 2b - 2 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 11 Pr Watershed 2 Hydrograph type = Combine Peak discharge = 0.044 cfs Storm frequency = 2 yrs Time to peak = 773 min Time interval = 1 min Hyd. volume = 912 cuft Inflow hyds. = 9, 10 Contrib. drain. area = 1.580 ac 26 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Pr Watershed 2 Hyd. No. 11 -- 2 Year Hyd No. 11 Hyd No. 9 Hyd No. 10 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 12 Proposed Conditions Hydrograph type = Combine Peak discharge = 0.044 cfs Storm frequency = 2 yrs Time to peak = 773 min Time interval = 1 min Hyd. volume = 917 cuft Inflow hyds. = 7, 11 Contrib. drain. area = 0.000 ac 27 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Proposed Conditions Hyd. No. 12 -- 2 Year Hyd No. 12 Hyd No. 7 Hyd No. 11 Hydrograph Summary Report 28 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 SCS Runoff 0.227 1 738 2,305 ------ ------ ------ Ex Watershed 1 2 SCS Runoff 0.172 1 773 3,367 ------ ------ ------ Ex Watershed 2 3 Combine 0.317 1 759 5,672 1, 2 ------ ------ Existing Conditions 4 SCS Runoff 5.133 1 732 20,802 ------ ------ ------ Pr Watershed 1a 5 Reservoir 0.119 1 1365 1,865 4 233.54 19,339 Basin 1 6 SCS Runoff 0.008 1 775 177 ------ ------ ------ Pr Watershed 1b 7 Combine 0.122 1 1357 2,042 5, 6 ------ ------ Pr Watershed 1 8 SCS Runoff 1.907 1 729 6,638 ------ ------ ------ Pr Watershed 2a 9 Reservoir 0.050 1 1155 1,033 8 233.52 5,680 Basin 2 10 SCS Runoff 0.746 1 731 3,938 ------ ------ ------ Pr Watershed 2b 11 Combine 0.746 1 731 4,970 9, 10 ------ ------ Pr Watershed 2 12 Combine 0.746 1 731 7,012 7, 11 ------ ------ Proposed Conditions Analysis.gpw Return Period: 10 Year Wednesday, 12 / 11 / 2024 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Hydrograph type = SCS Runoff Peak discharge = 0.227 cfs Storm frequency = 10 yrs Time to peak = 738 min Time interval = 1 min Hyd. volume = 2,305 cuft Drainage area = 1.440 ac Curve number = 44* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 10.30 min Total precip. = 5.12 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.620 x 36) + (0.790 x 49) + (0.030 x 98)] / 1.440 29 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) Ex Watershed 1 Hyd. No. 1 -- 10 Year Hyd No. 1 Precipitation Report 30 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Storm Frequency = 10 yrs Time interval = 1 min Total precip. = 5.1200 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 1 : Ex Watershed 1 - 10 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Hydrograph type = SCS Runoff Peak discharge = 0.172 cfs Storm frequency = 10 yrs Time to peak = 773 min Time interval = 1 min Hyd. volume = 3,367 cuft Drainage area = 3.500 ac Curve number = 40* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 20.40 min Total precip. = 5.12 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(2.870 x 36) + (0.540 x 49) + (0.090 x 98)] / 3.500 31 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) Ex Watershed 2 Hyd. No. 2 -- 10 Year Hyd No. 2 Precipitation Report 32 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Storm Frequency = 10 yrs Time interval = 1 min Total precip. = 5.1200 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 2 : Ex Watershed 2 - 10 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 3 Existing Conditions Hydrograph type = Combine Peak discharge = 0.317 cfs Storm frequency = 10 yrs Time to peak = 759 min Time interval = 1 min Hyd. volume = 5,672 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 4.940 ac 33 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) Existing Conditions Hyd. No. 3 -- 10 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Hydrograph type = SCS Runoff Peak discharge = 5.133 cfs Storm frequency = 10 yrs Time to peak = 732 min Time interval = 1 min Hyd. volume = 20,802 cuft Drainage area = 2.250 ac Curve number = 75* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 14.50 min Total precip. = 5.12 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.860 x 39) + (1.390 x 98)] / 2.250 34 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 5.00 5.00 6.00 6.00 Q (cfs) Time (min) Pr Watershed 1a Hyd. No. 4 -- 10 Year Hyd No. 4 Precipitation Report 35 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Storm Frequency = 10 yrs Time interval = 1 min Total precip. = 5.1200 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 4 : Pr Watershed 1a - 10 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 5 Basin 1 Hydrograph type = Reservoir Peak discharge = 0.119 cfs Storm frequency = 10 yrs Time to peak = 1365 min Time interval = 1 min Hyd. volume = 1,865 cuft Inflow hyd. No. = 4 - Pr Watershed 1a Max. Elevation = 233.54 ft Reservoir name = Pond 1 Max. Storage = 19,339 cuft Storage Indication method used. 36 0 180 360 540 720 900 1080 1260 1440 1620 1800 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 5.00 5.00 6.00 6.00 Q (cfs) Time (min) Basin 1 Hyd. No. 5 -- 10 Year Hyd No. 5 Hyd No. 4 Total storage used = 19,339 cuft Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Hydrograph type = SCS Runoff Peak discharge = 0.008 cfs Storm frequency = 10 yrs Time to peak = 775 min Time interval = 1 min Hyd. volume = 177 cuft Drainage area = 0.210 ac Curve number = 39* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 5.12 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.210 x 39)] / 0.210 37 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Pr Watershed 1b Hyd. No. 6 -- 10 Year Hyd No. 6 Precipitation Report 38 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Storm Frequency = 10 yrs Time interval = 1 min Total precip. = 5.1200 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 6 : Pr Watershed 1b - 10 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 7 Pr Watershed 1 Hydrograph type = Combine Peak discharge = 0.122 cfs Storm frequency = 10 yrs Time to peak = 1357 min Time interval = 1 min Hyd. volume = 2,042 cuft Inflow hyds. = 5, 6 Contrib. drain. area = 0.210 ac 39 0 180 360 540 720 900 1080 1260 1440 1620 1800 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) Pr Watershed 1 Hyd. No. 7 -- 10 Year Hyd No. 7 Hyd No. 5 Hyd No. 6 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Hydrograph type = SCS Runoff Peak discharge = 1.907 cfs Storm frequency = 10 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 6,638 cuft Drainage area = 0.770 ac Curve number = 73* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 8.80 min Total precip. = 5.12 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.320 x 39) + (0.450 x 98)] / 0.770 40 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Pr Watershed 2a Hyd. No. 8 -- 10 Year Hyd No. 8 Precipitation Report 41 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Storm Frequency = 10 yrs Time interval = 1 min Total precip. = 5.1200 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 8 : Pr Watershed 2a - 10 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 9 Basin 2 Hydrograph type = Reservoir Peak discharge = 0.050 cfs Storm frequency = 10 yrs Time to peak = 1155 min Time interval = 1 min Hyd. volume = 1,033 cuft Inflow hyd. No. = 8 - Pr Watershed 2a Max. Elevation = 233.52 ft Reservoir name = Pond 2 Max. Storage = 5,680 cuft Storage Indication method used. 42 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Basin 2 Hyd. No. 9 -- 10 Year Hyd No. 9 Hyd No. 8 Total storage used = 5,680 cuft Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Hydrograph type = SCS Runoff Peak discharge = 0.746 cfs Storm frequency = 10 yrs Time to peak = 731 min Time interval = 1 min Hyd. volume = 3,938 cuft Drainage area = 1.580 ac Curve number = 49* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 10.00 min Total precip. = 5.12 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.650 x 36) + (0.640 x 39) + (0.290 x 98)] / 1.580 43 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Pr Watershed 2b Hyd. No. 10 -- 10 Year Hyd No. 10 Precipitation Report 44 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Storm Frequency = 10 yrs Time interval = 1 min Total precip. = 5.1200 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 10 : Pr Watershed 2b - 10 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 11 Pr Watershed 2 Hydrograph type = Combine Peak discharge = 0.746 cfs Storm frequency = 10 yrs Time to peak = 731 min Time interval = 1 min Hyd. volume = 4,970 cuft Inflow hyds. = 9, 10 Contrib. drain. area = 1.580 ac 45 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Pr Watershed 2 Hyd. No. 11 -- 10 Year Hyd No. 11 Hyd No. 9 Hyd No. 10 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 12 Proposed Conditions Hydrograph type = Combine Peak discharge = 0.746 cfs Storm frequency = 10 yrs Time to peak = 731 min Time interval = 1 min Hyd. volume = 7,012 cuft Inflow hyds. = 7, 11 Contrib. drain. area = 0.000 ac 46 0 180 360 540 720 900 1080 1260 1440 1620 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Proposed Conditions Hyd. No. 12 -- 10 Year Hyd No. 12 Hyd No. 7 Hyd No. 11 Hydrograph Summary Report 47 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 SCS Runoff 0.723 1 732 4,254 ------ ------ ------ Ex Watershed 1 2 SCS Runoff 0.629 1 749 7,051 ------ ------ ------ Ex Watershed 2 3 Combine 1.093 1 738 11,305 1, 2 ------ ------ Existing Conditions 4 SCS Runoff 6.888 1 732 27,923 ------ ------ ------ Pr Watershed 1a 5 Reservoir 0.393 1 901 8,986 4 233.59 19,895 Basin 1 6 SCS Runoff 0.038 1 732 387 ------ ------ ------ Pr Watershed 1b 7 Combine 0.402 1 900 9,373 5, 6 ------ ------ Pr Watershed 1 8 SCS Runoff 2.590 1 729 9,005 ------ ------ ------ Pr Watershed 2a 9 Reservoir 0.183 1 843 3,400 8 233.57 5,834 Basin 2 10 SCS Runoff 1.554 1 730 6,585 ------ ------ ------ Pr Watershed 2b 11 Combine 1.554 1 730 9,985 9, 10 ------ ------ Pr Watershed 2 12 Combine 1.591 1 730 19,358 7, 11 ------ ------ Proposed Conditions Analysis.gpw Return Period: 25 Year Wednesday, 12 / 11 / 2024 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Hydrograph type = SCS Runoff Peak discharge = 0.723 cfs Storm frequency = 25 yrs Time to peak = 732 min Time interval = 1 min Hyd. volume = 4,254 cuft Drainage area = 1.440 ac Curve number = 44* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 10.30 min Total precip. = 6.16 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.620 x 36) + (0.790 x 49) + (0.030 x 98)] / 1.440 48 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Ex Watershed 1 Hyd. No. 1 -- 25 Year Hyd No. 1 Precipitation Report 49 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Storm Frequency = 25 yrs Time interval = 1 min Total precip. = 6.1600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 1 : Ex Watershed 1 - 25 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Hydrograph type = SCS Runoff Peak discharge = 0.629 cfs Storm frequency = 25 yrs Time to peak = 749 min Time interval = 1 min Hyd. volume = 7,051 cuft Drainage area = 3.500 ac Curve number = 40* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 20.40 min Total precip. = 6.16 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(2.870 x 36) + (0.540 x 49) + (0.090 x 98)] / 3.500 50 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Ex Watershed 2 Hyd. No. 2 -- 25 Year Hyd No. 2 Precipitation Report 51 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Storm Frequency = 25 yrs Time interval = 1 min Total precip. = 6.1600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 2 : Ex Watershed 2 - 25 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 3 Existing Conditions Hydrograph type = Combine Peak discharge = 1.093 cfs Storm frequency = 25 yrs Time to peak = 738 min Time interval = 1 min Hyd. volume = 11,305 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 4.940 ac 52 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Existing Conditions Hyd. No. 3 -- 25 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Hydrograph type = SCS Runoff Peak discharge = 6.888 cfs Storm frequency = 25 yrs Time to peak = 732 min Time interval = 1 min Hyd. volume = 27,923 cuft Drainage area = 2.250 ac Curve number = 75* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 14.50 min Total precip. = 6.16 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.860 x 39) + (1.390 x 98)] / 2.250 53 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 5.00 5.00 6.00 6.00 7.00 7.00 Q (cfs) Time (min) Pr Watershed 1a Hyd. No. 4 -- 25 Year Hyd No. 4 Precipitation Report 54 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Storm Frequency = 25 yrs Time interval = 1 min Total precip. = 6.1600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 4 : Pr Watershed 1a - 25 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 5 Basin 1 Hydrograph type = Reservoir Peak discharge = 0.393 cfs Storm frequency = 25 yrs Time to peak = 901 min Time interval = 1 min Hyd. volume = 8,986 cuft Inflow hyd. No. = 4 - Pr Watershed 1a Max. Elevation = 233.59 ft Reservoir name = Pond 1 Max. Storage = 19,895 cuft Storage Indication method used. 55 0 180 360 540 720 900 1080 1260 1440 1620 1800 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 5.00 5.00 6.00 6.00 7.00 7.00 Q (cfs) Time (min) Basin 1 Hyd. No. 5 -- 25 Year Hyd No. 5 Hyd No. 4 Total storage used = 19,895 cuft Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Hydrograph type = SCS Runoff Peak discharge = 0.038 cfs Storm frequency = 25 yrs Time to peak = 732 min Time interval = 1 min Hyd. volume = 387 cuft Drainage area = 0.210 ac Curve number = 39* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 6.16 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.210 x 39)] / 0.210 56 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 0.07 0.08 0.08 0.09 0.09 0.10 0.10 Q (cfs) Time (min) Pr Watershed 1b Hyd. No. 6 -- 25 Year Hyd No. 6 Precipitation Report 57 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Storm Frequency = 25 yrs Time interval = 1 min Total precip. = 6.1600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 6 : Pr Watershed 1b - 25 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 7 Pr Watershed 1 Hydrograph type = Combine Peak discharge = 0.402 cfs Storm frequency = 25 yrs Time to peak = 900 min Time interval = 1 min Hyd. volume = 9,373 cuft Inflow hyds. = 5, 6 Contrib. drain. area = 0.210 ac 58 0 180 360 540 720 900 1080 1260 1440 1620 1800 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) Pr Watershed 1 Hyd. No. 7 -- 25 Year Hyd No. 7 Hyd No. 5 Hyd No. 6 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Hydrograph type = SCS Runoff Peak discharge = 2.590 cfs Storm frequency = 25 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 9,005 cuft Drainage area = 0.770 ac Curve number = 73* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 8.80 min Total precip. = 6.16 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.320 x 39) + (0.450 x 98)] / 0.770 59 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Pr Watershed 2a Hyd. No. 8 -- 25 Year Hyd No. 8 Precipitation Report 60 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Storm Frequency = 25 yrs Time interval = 1 min Total precip. = 6.1600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 8 : Pr Watershed 2a - 25 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 9 Basin 2 Hydrograph type = Reservoir Peak discharge = 0.183 cfs Storm frequency = 25 yrs Time to peak = 843 min Time interval = 1 min Hyd. volume = 3,400 cuft Inflow hyd. No. = 8 - Pr Watershed 2a Max. Elevation = 233.57 ft Reservoir name = Pond 2 Max. Storage = 5,834 cuft Storage Indication method used. 61 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Basin 2 Hyd. No. 9 -- 25 Year Hyd No. 9 Hyd No. 8 Total storage used = 5,834 cuft Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Hydrograph type = SCS Runoff Peak discharge = 1.554 cfs Storm frequency = 25 yrs Time to peak = 730 min Time interval = 1 min Hyd. volume = 6,585 cuft Drainage area = 1.580 ac Curve number = 49* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 10.00 min Total precip. = 6.16 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.650 x 36) + (0.640 x 39) + (0.290 x 98)] / 1.580 62 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Pr Watershed 2b Hyd. No. 10 -- 25 Year Hyd No. 10 Precipitation Report 63 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Storm Frequency = 25 yrs Time interval = 1 min Total precip. = 6.1600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 10 : Pr Watershed 2b - 25 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 11 Pr Watershed 2 Hydrograph type = Combine Peak discharge = 1.554 cfs Storm frequency = 25 yrs Time to peak = 730 min Time interval = 1 min Hyd. volume = 9,985 cuft Inflow hyds. = 9, 10 Contrib. drain. area = 1.580 ac 64 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Pr Watershed 2 Hyd. No. 11 -- 25 Year Hyd No. 11 Hyd No. 9 Hyd No. 10 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 12 Proposed Conditions Hydrograph type = Combine Peak discharge = 1.591 cfs Storm frequency = 25 yrs Time to peak = 730 min Time interval = 1 min Hyd. volume = 19,358 cuft Inflow hyds. = 7, 11 Contrib. drain. area = 0.000 ac 65 0 180 360 540 720 900 1080 1260 1440 1620 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Proposed Conditions Hyd. No. 12 -- 25 Year Hyd No. 12 Hyd No. 7 Hyd No. 11 Hydrograph Summary Report 66 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 SCS Runoff 1.220 1 732 6,001 ------ ------ ------ Ex Watershed 1 2 SCS Runoff 1.235 1 744 10,512 ------ ------ ------ Ex Watershed 2 3 Combine 2.097 1 737 16,513 1, 2 ------ ------ Existing Conditions 4 SCS Runoff 8.233 1 732 33,459 ------ ------ ------ Pr Watershed 1a 5 Reservoir 0.874 1 810 14,522 4 233.66 20,578 Basin 1 6 SCS Runoff 0.102 1 729 587 ------ ------ ------ Pr Watershed 1b 7 Combine 0.896 1 810 15,109 5, 6 ------ ------ Pr Watershed 1 8 SCS Runoff 3.115 1 729 10,855 ------ ------ ------ Pr Watershed 2a 9 Reservoir 0.428 1 780 5,250 8 233.62 6,019 Basin 2 10 SCS Runoff 2.246 1 730 8,868 ------ ------ ------ Pr Watershed 2b 11 Combine 2.246 1 730 14,117 9, 10 ------ ------ Pr Watershed 2 12 Combine 2.343 1 730 29,226 7, 11 ------ ------ Proposed Conditions Analysis.gpw Return Period: 50 Year Wednesday, 12 / 11 / 2024 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Hydrograph type = SCS Runoff Peak discharge = 1.220 cfs Storm frequency = 50 yrs Time to peak = 732 min Time interval = 1 min Hyd. volume = 6,001 cuft Drainage area = 1.440 ac Curve number = 44* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 10.30 min Total precip. = 6.94 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.620 x 36) + (0.790 x 49) + (0.030 x 98)] / 1.440 67 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Ex Watershed 1 Hyd. No. 1 -- 50 Year Hyd No. 1 Precipitation Report 68 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Storm Frequency = 50 yrs Time interval = 1 min Total precip. = 6.9400 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 1 : Ex Watershed 1 - 50 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Hydrograph type = SCS Runoff Peak discharge = 1.235 cfs Storm frequency = 50 yrs Time to peak = 744 min Time interval = 1 min Hyd. volume = 10,512 cuft Drainage area = 3.500 ac Curve number = 40* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 20.40 min Total precip. = 6.94 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(2.870 x 36) + (0.540 x 49) + (0.090 x 98)] / 3.500 69 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Ex Watershed 2 Hyd. No. 2 -- 50 Year Hyd No. 2 Precipitation Report 70 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Storm Frequency = 50 yrs Time interval = 1 min Total precip. = 6.9400 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 2 : Ex Watershed 2 - 50 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 3 Existing Conditions Hydrograph type = Combine Peak discharge = 2.097 cfs Storm frequency = 50 yrs Time to peak = 737 min Time interval = 1 min Hyd. volume = 16,513 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 4.940 ac 71 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Existing Conditions Hyd. No. 3 -- 50 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Hydrograph type = SCS Runoff Peak discharge = 8.233 cfs Storm frequency = 50 yrs Time to peak = 732 min Time interval = 1 min Hyd. volume = 33,459 cuft Drainage area = 2.250 ac Curve number = 75* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 14.50 min Total precip. = 6.94 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.860 x 39) + (1.390 x 98)] / 2.250 72 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 Q (cfs) Time (min) Pr Watershed 1a Hyd. No. 4 -- 50 Year Hyd No. 4 Precipitation Report 73 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Storm Frequency = 50 yrs Time interval = 1 min Total precip. = 6.9400 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 4 : Pr Watershed 1a - 50 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 5 Basin 1 Hydrograph type = Reservoir Peak discharge = 0.874 cfs Storm frequency = 50 yrs Time to peak = 810 min Time interval = 1 min Hyd. volume = 14,522 cuft Inflow hyd. No. = 4 - Pr Watershed 1a Max. Elevation = 233.66 ft Reservoir name = Pond 1 Max. Storage = 20,578 cuft Storage Indication method used. 74 0 180 360 540 720 900 1080 1260 1440 1620 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 Q (cfs) Time (min) Basin 1 Hyd. No. 5 -- 50 Year Hyd No. 5 Hyd No. 4 Total storage used = 20,578 cuft Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Hydrograph type = SCS Runoff Peak discharge = 0.102 cfs Storm frequency = 50 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 587 cuft Drainage area = 0.210 ac Curve number = 39* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 6.94 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.210 x 39)] / 0.210 75 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) Pr Watershed 1b Hyd. No. 6 -- 50 Year Hyd No. 6 Precipitation Report 76 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Storm Frequency = 50 yrs Time interval = 1 min Total precip. = 6.9400 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 6 : Pr Watershed 1b - 50 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 7 Pr Watershed 1 Hydrograph type = Combine Peak discharge = 0.896 cfs Storm frequency = 50 yrs Time to peak = 810 min Time interval = 1 min Hyd. volume = 15,109 cuft Inflow hyds. = 5, 6 Contrib. drain. area = 0.210 ac 77 0 180 360 540 720 900 1080 1260 1440 1620 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Pr Watershed 1 Hyd. No. 7 -- 50 Year Hyd No. 7 Hyd No. 5 Hyd No. 6 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Hydrograph type = SCS Runoff Peak discharge = 3.115 cfs Storm frequency = 50 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 10,855 cuft Drainage area = 0.770 ac Curve number = 73* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 8.80 min Total precip. = 6.94 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.320 x 39) + (0.450 x 98)] / 0.770 78 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 Q (cfs) Time (min) Pr Watershed 2a Hyd. No. 8 -- 50 Year Hyd No. 8 Precipitation Report 79 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Storm Frequency = 50 yrs Time interval = 1 min Total precip. = 6.9400 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 8 : Pr Watershed 2a - 50 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 9 Basin 2 Hydrograph type = Reservoir Peak discharge = 0.428 cfs Storm frequency = 50 yrs Time to peak = 780 min Time interval = 1 min Hyd. volume = 5,250 cuft Inflow hyd. No. = 8 - Pr Watershed 2a Max. Elevation = 233.62 ft Reservoir name = Pond 2 Max. Storage = 6,019 cuft Storage Indication method used. 80 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 Q (cfs) Time (min) Basin 2 Hyd. No. 9 -- 50 Year Hyd No. 9 Hyd No. 8 Total storage used = 6,019 cuft Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Hydrograph type = SCS Runoff Peak discharge = 2.246 cfs Storm frequency = 50 yrs Time to peak = 730 min Time interval = 1 min Hyd. volume = 8,868 cuft Drainage area = 1.580 ac Curve number = 49* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 10.00 min Total precip. = 6.94 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.650 x 36) + (0.640 x 39) + (0.290 x 98)] / 1.580 81 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Pr Watershed 2b Hyd. No. 10 -- 50 Year Hyd No. 10 Precipitation Report 82 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Storm Frequency = 50 yrs Time interval = 1 min Total precip. = 6.9400 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 10 : Pr Watershed 2b - 50 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 11 Pr Watershed 2 Hydrograph type = Combine Peak discharge = 2.246 cfs Storm frequency = 50 yrs Time to peak = 730 min Time interval = 1 min Hyd. volume = 14,117 cuft Inflow hyds. = 9, 10 Contrib. drain. area = 1.580 ac 83 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Pr Watershed 2 Hyd. No. 11 -- 50 Year Hyd No. 11 Hyd No. 9 Hyd No. 10 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 12 Proposed Conditions Hydrograph type = Combine Peak discharge = 2.343 cfs Storm frequency = 50 yrs Time to peak = 730 min Time interval = 1 min Hyd. volume = 29,226 cuft Inflow hyds. = 7, 11 Contrib. drain. area = 0.000 ac 84 0 180 360 540 720 900 1080 1260 1440 1620 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Proposed Conditions Hyd. No. 12 -- 50 Year Hyd No. 12 Hyd No. 7 Hyd No. 11 Hydrograph Summary Report 85 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 SCS Runoff 1.814 1 731 8,063 ------ ------ ------ Ex Watershed 1 2 SCS Runoff 2.083 1 741 14,708 ------ ------ ------ Ex Watershed 2 3 Combine 3.427 1 736 22,772 1, 2 ------ ------ Existing Conditions 4 SCS Runoff 9.663 1 732 39,413 ------ ------ ------ Pr Watershed 1a 5 Reservoir 1.677 1 776 20,476 4 233.75 21,482 Basin 1 6 SCS Runoff 0.186 1 728 832 ------ ------ ------ Pr Watershed 1b 7 Combine 1.722 1 775 21,308 5, 6 ------ ------ Pr Watershed 1 8 SCS Runoff 3.675 1 729 12,852 ------ ------ ------ Pr Watershed 2a 9 Reservoir 0.830 1 754 7,246 8 233.69 6,254 Basin 2 10 SCS Runoff 3.040 1 729 11,496 ------ ------ ------ Pr Watershed 2b 11 Combine 3.040 1 729 18,742 9, 10 ------ ------ Pr Watershed 2 12 Combine 3.224 1 729 40,050 7, 11 ------ ------ Proposed Conditions Analysis.gpw Return Period: 100 Year Wednesday, 12 / 11 / 2024 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Hydrograph type = SCS Runoff Peak discharge = 1.814 cfs Storm frequency = 100 yrs Time to peak = 731 min Time interval = 1 min Hyd. volume = 8,063 cuft Drainage area = 1.440 ac Curve number = 44* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 10.30 min Total precip. = 7.76 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.620 x 36) + (0.790 x 49) + (0.030 x 98)] / 1.440 86 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Ex Watershed 1 Hyd. No. 1 -- 100 Year Hyd No. 1 Precipitation Report 87 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 1 Ex Watershed 1 Storm Frequency = 100 yrs Time interval = 1 min Total precip. = 7.7600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 1 : Ex Watershed 1 - 100 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Hydrograph type = SCS Runoff Peak discharge = 2.083 cfs Storm frequency = 100 yrs Time to peak = 741 min Time interval = 1 min Hyd. volume = 14,708 cuft Drainage area = 3.500 ac Curve number = 40* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 20.40 min Total precip. = 7.76 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(2.870 x 36) + (0.540 x 49) + (0.090 x 98)] / 3.500 88 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 Q (cfs) Time (min) Ex Watershed 2 Hyd. No. 2 -- 100 Year Hyd No. 2 Precipitation Report 89 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 2 Ex Watershed 2 Storm Frequency = 100 yrs Time interval = 1 min Total precip. = 7.7600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 2 : Ex Watershed 2 - 100 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 3 Existing Conditions Hydrograph type = Combine Peak discharge = 3.427 cfs Storm frequency = 100 yrs Time to peak = 736 min Time interval = 1 min Hyd. volume = 22,772 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 4.940 ac 90 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 Q (cfs) Time (min) Existing Conditions Hyd. No. 3 -- 100 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Hydrograph type = SCS Runoff Peak discharge = 9.663 cfs Storm frequency = 100 yrs Time to peak = 732 min Time interval = 1 min Hyd. volume = 39,413 cuft Drainage area = 2.250 ac Curve number = 75* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 14.50 min Total precip. = 7.76 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.860 x 39) + (1.390 x 98)] / 2.250 91 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 Q (cfs) Time (min) Pr Watershed 1a Hyd. No. 4 -- 100 Year Hyd No. 4 Precipitation Report 92 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 4 Pr Watershed 1a Storm Frequency = 100 yrs Time interval = 1 min Total precip. = 7.7600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 4 : Pr Watershed 1a - 100 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 5 Basin 1 Hydrograph type = Reservoir Peak discharge = 1.677 cfs Storm frequency = 100 yrs Time to peak = 776 min Time interval = 1 min Hyd. volume = 20,476 cuft Inflow hyd. No. = 4 - Pr Watershed 1a Max. Elevation = 233.75 ft Reservoir name = Pond 1 Max. Storage = 21,482 cuft Storage Indication method used. 93 0 180 360 540 720 900 1080 1260 1440 1620 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 Q (cfs) Time (min) Basin 1 Hyd. No. 5 -- 100 Year Hyd No. 5 Hyd No. 4 Total storage used = 21,482 cuft Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Hydrograph type = SCS Runoff Peak discharge = 0.186 cfs Storm frequency = 100 yrs Time to peak = 728 min Time interval = 1 min Hyd. volume = 832 cuft Drainage area = 0.210 ac Curve number = 39* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 7.76 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.210 x 39)] / 0.210 94 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) Pr Watershed 1b Hyd. No. 6 -- 100 Year Hyd No. 6 Precipitation Report 95 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 6 Pr Watershed 1b Storm Frequency = 100 yrs Time interval = 1 min Total precip. = 7.7600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 6 : Pr Watershed 1b - 100 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 7 Pr Watershed 1 Hydrograph type = Combine Peak discharge = 1.722 cfs Storm frequency = 100 yrs Time to peak = 775 min Time interval = 1 min Hyd. volume = 21,308 cuft Inflow hyds. = 5, 6 Contrib. drain. area = 0.210 ac 96 0 180 360 540 720 900 1080 1260 1440 1620 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 Q (cfs) Time (min) Pr Watershed 1 Hyd. No. 7 -- 100 Year Hyd No. 7 Hyd No. 5 Hyd No. 6 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Hydrograph type = SCS Runoff Peak discharge = 3.675 cfs Storm frequency = 100 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 12,852 cuft Drainage area = 0.770 ac Curve number = 73* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 8.80 min Total precip. = 7.76 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.320 x 39) + (0.450 x 98)] / 0.770 97 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 Q (cfs) Time (min) Pr Watershed 2a Hyd. No. 8 -- 100 Year Hyd No. 8 Precipitation Report 98 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 8 Pr Watershed 2a Storm Frequency = 100 yrs Time interval = 1 min Total precip. = 7.7600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 8 : Pr Watershed 2a - 100 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 9 Basin 2 Hydrograph type = Reservoir Peak discharge = 0.830 cfs Storm frequency = 100 yrs Time to peak = 754 min Time interval = 1 min Hyd. volume = 7,246 cuft Inflow hyd. No. = 8 - Pr Watershed 2a Max. Elevation = 233.69 ft Reservoir name = Pond 2 Max. Storage = 6,254 cuft Storage Indication method used. 99 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 Q (cfs) Time (min) Basin 2 Hyd. No. 9 -- 100 Year Hyd No. 9 Hyd No. 8 Total storage used = 6,254 cuft Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Hydrograph type = SCS Runoff Peak discharge = 3.040 cfs Storm frequency = 100 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 11,496 cuft Drainage area = 1.580 ac Curve number = 49* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 10.00 min Total precip. = 7.76 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\DrShape factor = 484 * Composite (Area/CN) = [(0.650 x 36) + (0.640 x 39) + (0.290 x 98)] / 1.580 100 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 Q (cfs) Time (min) Pr Watershed 2b Hyd. No. 10 -- 100 Year Hyd No. 10 Precipitation Report 101 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 10 Pr Watershed 2b Storm Frequency = 100 yrs Time interval = 1 min Total precip. = 7.7600 in Distribution = Custom Storm duration = M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\D 0 140 280 420 560 700 840 980 1120 1260 1400 1540 Precip (in) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Precip (in) Time (min)Custom Design Storm -- M:\7000\7700\7767F - Rand Whitney Stormwater Design\Studies-Calculations\Drainage\Ana Incremental Rainfall Precipitation Hyd. No. 10 : Pr Watershed 2b - 100 Year Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 11 Pr Watershed 2 Hydrograph type = Combine Peak discharge = 3.040 cfs Storm frequency = 100 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 18,742 cuft Inflow hyds. = 9, 10 Contrib. drain. area = 1.580 ac 102 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 Q (cfs) Time (min) Pr Watershed 2 Hyd. No. 11 -- 100 Year Hyd No. 11 Hyd No. 9 Hyd No. 10 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2024 Wednesday, 12 / 11 / 2024 Hyd. No. 12 Proposed Conditions Hydrograph type = Combine Peak discharge = 3.224 cfs Storm frequency = 100 yrs Time to peak = 729 min Time interval = 1 min Hyd. volume = 40,050 cuft Inflow hyds. = 7, 11 Contrib. drain. area = 0.000 ac 103 0 180 360 540 720 900 1080 1260 1440 1620 Q (cfs) 0.00 0.00 1.00 1.00 2.00 2.00 3.00 3.00 4.00 4.00 Q (cfs) Time (min) Proposed Conditions Hyd. No. 12 -- 100 Year Hyd No. 12 Hyd No. 7 Hyd No. 11 CLA Engineers, Inc. Civil · Structural · Survey Appendix B Rainfall Data NOAA Atlas 14, Volume 10, Version 3 Location name: Uncasville, Connecticut, USA* Latitude: 41.453°, Longitude: -72.1399° Elevation: 240 ft** * source: ESRI Maps** source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Sandra Pavlovic, Michael St. Laurent, Carl Trypaluk, Dale Unruh, Orlan Wilhite NOAA, National Weather Service, Silver Spring, Maryland PF_tabular | PF_graphical | Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Duration Average recurrence interval (years) 1 2 5 10 25 50 100 200 500 1000 5-min 0.340 (0.265‑0.426) 0.406 (0.316‑0.509) 0.514 (0.399‑0.647) 0.604 (0.466‑0.763) 0.728 (0.544‑0.953) 0.821 (0.601‑1.09) 0.918 (0.654‑1.26) 1.03 (0.693‑1.44) 1.19 (0.770‑1.70) 1.32 (0.836‑1.93) 10-min 0.482 (0.375‑0.603) 0.576 (0.448‑0.721) 0.729 (0.566‑0.916) 0.856 (0.660‑1.08) 1.03 (0.771‑1.35) 1.16 (0.852‑1.55) 1.30 (0.926‑1.79) 1.46 (0.982‑2.03) 1.68 (1.09‑2.42) 1.87 (1.18‑2.73) 15-min 0.567 (0.442‑0.710) 0.677 (0.527‑0.849) 0.857 (0.665‑1.08) 1.01 (0.777‑1.27) 1.21 (0.907‑1.59) 1.37 (1.00‑1.82) 1.53 (1.09‑2.10) 1.72 (1.16‑2.39) 1.98 (1.28‑2.84) 2.20 (1.39‑3.21) 30-min 0.798 (0.622‑1.00) 0.953 (0.742‑1.20) 1.21 (0.937‑1.52) 1.42 (1.09‑1.79) 1.71 (1.28‑2.24) 1.92 (1.41‑2.56) 2.15 (1.53‑2.96) 2.41 (1.62‑3.36) 2.78 (1.80‑4.00) 3.09 (1.96‑4.51) 60-min 1.03 (0.802‑1.29) 1.23 (0.957‑1.54) 1.56 (1.21‑1.96) 1.83 (1.41‑2.31) 2.20 (1.64‑2.88) 2.48 (1.82‑3.31) 2.78 (1.98‑3.82) 3.11 (2.10‑4.34) 3.59 (2.33‑5.15) 3.98 (2.52‑5.81) 2-hr 1.35 (1.06‑1.68) 1.61 (1.27‑2.01) 2.04 (1.59‑2.54) 2.39 (1.86‑3.00) 2.88 (2.17‑3.74) 3.24 (2.39‑4.29) 3.63 (2.60‑4.96) 4.07 (2.76‑5.63) 4.73 (3.08‑6.72) 5.27 (3.35‑7.62) 3-hr 1.57 (1.24‑1.95) 1.87 (1.48‑2.32) 2.36 (1.86‑2.94) 2.77 (2.16‑3.46) 3.33 (2.52‑4.32) 3.75 (2.78‑4.94) 4.19 (3.02‑5.71) 4.71 (3.20‑6.48) 5.48 (3.57‑7.75) 6.12 (3.90‑8.79) 6-hr 2.00 (1.59‑2.46) 2.37 (1.88‑2.92) 2.99 (2.36‑3.69) 3.50 (2.75‑4.33) 4.20 (3.19‑5.39) 4.72 (3.52‑6.17) 5.27 (3.82‑7.12) 5.92 (4.04‑8.08) 6.88 (4.51‑9.64) 7.68 (4.91‑10.9) 12-hr 2.47 (1.98‑3.02) 2.93 (2.34‑3.58) 3.68 (2.93‑4.51) 4.30 (3.41‑5.30) 5.16 (3.95‑6.58) 5.80 (4.35‑7.53) 6.48 (4.72‑8.67) 7.27 (4.98‑9.83) 8.42 (5.54‑11.7) 9.38 (6.02‑13.2) 24-hr 2.90 (2.34‑3.52) 3.45 (2.78‑4.20) 4.36 (3.50‑5.31) 5.12 (4.08‑6.26) 6.16 (4.75‑7.80) 6.94 (5.24‑8.93) 7.76 (5.69‑10.3) 8.72 (6.01‑11.7) 10.1 (6.71‑14.0) 11.3 (7.31‑15.8) 2-day 3.25 (2.64‑3.91) 3.91 (3.18‑4.72) 5.00 (4.04‑6.04) 5.90 (4.74‑7.16) 7.14 (5.55‑8.99) 8.06 (6.14‑10.3) 9.06 (6.70‑12.0) 10.2 (7.09‑13.6) 12.0 (7.98‑16.4) 13.6 (8.77‑18.8) 3-day 3.52 (2.88‑4.23) 4.24 (3.46‑5.10) 5.42 (4.40‑6.53) 6.40 (5.16‑7.73) 7.74 (6.05‑9.71) 8.74 (6.68‑11.2) 9.82 (7.29‑12.9) 11.1 (7.71‑14.7) 13.1 (8.69‑17.7) 14.7 (9.55‑20.3) 4-day 3.78 (3.10‑4.53) 4.54 (3.72‑5.44) 5.78 (4.71‑6.94) 6.81 (5.51‑8.20) 8.22 (6.44‑10.3) 9.27 (7.11‑11.8) 10.4 (7.74‑13.7) 11.8 (8.18‑15.5) 13.8 (9.20‑18.7) 15.6 (10.1‑21.3) 7-day 4.52 (3.72‑5.37) 5.34 (4.40‑6.36) 6.70 (5.50‑8.00) 7.83 (6.38‑9.38) 9.38 (7.38‑11.6) 10.5 (8.10‑13.3) 11.8 (8.78‑15.3) 13.2 (9.24‑17.3) 15.4 (10.3‑20.6) 17.2 (11.2‑23.4) 10-day 5.24 (4.33‑6.21) 6.10 (5.05‑7.24) 7.53 (6.20‑8.95) 8.71 (7.12‑10.4) 10.3 (8.15‑12.7) 11.5 (8.90‑14.5) 12.8 (9.57‑16.5) 14.3 (10.0‑18.6) 16.5 (11.1‑22.0) 18.3 (12.0‑24.8) 20-day 7.45 (6.21‑8.76) 8.37 (6.98‑9.86) 9.89 (8.20‑11.7) 11.1 (9.19‑13.2) 12.9 (10.2‑15.7) 14.2 (11.0‑17.5) 15.5 (11.6‑19.6) 17.0 (12.0‑21.8) 18.9 (12.8‑24.9) 20.4 (13.4‑27.3) 30-day 9.29 (7.78‑10.9) 10.2 (8.58‑12.0) 11.8 (9.85‑13.9) 13.1 (10.9‑15.5) 14.9 (11.9‑18.0) 16.3 (12.6‑19.9) 17.7 (13.1‑22.0) 19.0 (13.5‑24.3) 20.7 (14.1‑27.2) 22.0 (14.5‑29.3) 45-day 11.6 (9.74‑13.5) 12.6 (10.6‑14.7) 14.2 (11.9‑16.6) 15.6 (13.0‑18.3) 17.5 (13.9‑20.9) 19.0 (14.7‑23.0) 20.4 (15.1‑25.1) 21.6 (15.4‑27.5) 23.2 (15.8‑30.2) 24.2 (15.9‑32.0) 60-day 13.5 (11.4‑15.7) 14.5 (12.2‑16.9) 16.2 (13.6‑18.9) 17.7 (14.7‑20.7) 19.6 (15.7‑23.4) 21.2 (16.5‑25.6) 22.7 (16.8‑27.8) 23.9 (17.1‑30.3) 25.3 (17.3‑32.9) 26.2 (17.4‑34.5) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequencyestimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates atupper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical 10/1/24, 11:48 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=41.4530&lon=-72.1399&data=depth&units=english&series=pds 1/4 Back to Top Maps & aerials Small scale terrain 10/1/24, 11:48 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=41.4530&lon=-72.1399&data=depth&units=english&series=pds 2/4 Large scale terrain Large scale map Large scale aerial + – 3km 2mi + – 100km 60mi + – 100km 60mi 10/1/24, 11:48 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=41.4530&lon=-72.1399&data=depth&units=english&series=pds 3/4 Back to Top US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service National Water Center 1325 East West Highway Silver Spring, MD 20910 Questions?: HDSC.Questions@noaa.gov Disclaimer + – 100km 60mi 10/1/24, 11:48 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=41.4530&lon=-72.1399&data=depth&units=english&series=pds 4/4 NOAA Atlas 14, Volume 10, Version 3 Location name: Uncasville, Connecticut, USA* Latitude: 41.453°, Longitude: -72.1399° Elevation: 240 ft** * source: ESRI Maps** source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Sandra Pavlovic, Michael St. Laurent, Carl Trypaluk, Dale Unruh, Orlan Wilhite NOAA, National Weather Service, Silver Spring, Maryland PF_tabular | PF_graphical | Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hour)1 Duration Average recurrence interval (years) 1 2 5 10 25 50 100 200 500 1000 5-min 4.08 (3.18‑5.11) 4.87 (3.79‑6.11) 6.17 (4.79‑7.76) 7.25 (5.59‑9.16) 8.74 (6.53‑11.4) 9.85 (7.21‑13.1) 11.0 (7.85‑15.1) 12.3 (8.32‑17.2) 14.3 (9.24‑20.5) 15.9 (10.0‑23.1) 10-min 2.89 (2.25‑3.62) 3.46 (2.69‑4.33) 4.37 (3.40‑5.50) 5.14 (3.96‑6.49) 6.19 (4.63‑8.10) 6.98 (5.11‑9.29) 7.81 (5.56‑10.7) 8.75 (5.89‑12.2) 10.1 (6.55‑14.5) 11.2 (7.10‑16.4) 15-min 2.27 (1.77‑2.84) 2.71 (2.11‑3.40) 3.43 (2.66‑4.31) 4.03 (3.11‑5.08) 4.85 (3.63‑6.35) 5.47 (4.01‑7.29) 6.12 (4.36‑8.42) 6.86 (4.62‑9.58) 7.93 (5.14‑11.4) 8.80 (5.57‑12.8) 30-min 1.60 (1.24‑2.00) 1.91 (1.48‑2.39) 2.41 (1.87‑3.03) 2.83 (2.19‑3.58) 3.41 (2.55‑4.47) 3.85 (2.82‑5.13) 4.31 (3.06‑5.92) 4.83 (3.25‑6.73) 5.57 (3.61‑7.99) 6.18 (3.91‑9.02) 60-min 1.03 (0.802‑1.29) 1.23 (0.957‑1.54) 1.56 (1.21‑1.96) 1.83 (1.41‑2.31) 2.20 (1.64‑2.88) 2.48 (1.82‑3.31) 2.78 (1.98‑3.82) 3.11 (2.10‑4.34) 3.59 (2.33‑5.15) 3.98 (2.52‑5.81) 2-hr 0.677 (0.531‑0.842) 0.807 (0.633‑1.00) 1.02 (0.797‑1.27) 1.20 (0.930‑1.50) 1.44 (1.08‑1.87) 1.62 (1.20‑2.15) 1.81 (1.30‑2.48) 2.04 (1.38‑2.82) 2.36 (1.54‑3.36) 2.64 (1.67‑3.81) 3-hr 0.523 (0.413‑0.649) 0.623 (0.491‑0.773) 0.787 (0.617‑0.978) 0.922 (0.719‑1.15) 1.11 (0.838‑1.44) 1.25 (0.924‑1.65) 1.40 (1.00‑1.90) 1.57 (1.06‑2.16) 1.82 (1.19‑2.58) 2.04 (1.30‑2.93) 6-hr 0.334 (0.265‑0.410) 0.396 (0.314‑0.488) 0.498 (0.394‑0.615) 0.583 (0.458‑0.723) 0.700 (0.533‑0.900) 0.787 (0.587‑1.03) 0.880 (0.637‑1.19) 0.988 (0.674‑1.35) 1.15 (0.752‑1.61) 1.28 (0.820‑1.83) 12-hr 0.205 (0.164‑0.250) 0.243 (0.194‑0.297) 0.305 (0.243‑0.374) 0.357 (0.282‑0.439) 0.428 (0.328‑0.546) 0.481 (0.361‑0.624) 0.537 (0.391‑0.719) 0.603 (0.413‑0.815) 0.698 (0.459‑0.970) 0.778 (0.499‑1.10) 24-hr 0.120 (0.097‑0.146) 0.143 (0.115‑0.174) 0.181 (0.145‑0.221) 0.213 (0.170‑0.260) 0.256 (0.197‑0.325) 0.288 (0.218‑0.372) 0.323 (0.237‑0.429) 0.363 (0.250‑0.487) 0.422 (0.279‑0.582) 0.472 (0.304‑0.660) 2-day 0.067 (0.054‑0.081) 0.081 (0.066‑0.098) 0.104 (0.084‑0.125) 0.122 (0.098‑0.149) 0.148 (0.115‑0.187) 0.167 (0.127‑0.215) 0.188 (0.139‑0.249) 0.213 (0.147‑0.283) 0.250 (0.166‑0.341) 0.282 (0.182‑0.390) 3-day 0.048 (0.039‑0.058) 0.058 (0.048‑0.070) 0.075 (0.061‑0.090) 0.088 (0.071‑0.107) 0.107 (0.083‑0.134) 0.121 (0.092‑0.154) 0.136 (0.101‑0.179) 0.154 (0.107‑0.204) 0.181 (0.120‑0.246) 0.204 (0.132‑0.281) 4-day 0.039 (0.032‑0.047) 0.047 (0.038‑0.056) 0.060 (0.049‑0.072) 0.070 (0.057‑0.085) 0.085 (0.067‑0.107) 0.096 (0.074‑0.122) 0.108 (0.080‑0.142) 0.122 (0.085‑0.161) 0.143 (0.095‑0.194) 0.162 (0.105‑0.222) 7-day 0.026 (0.022‑0.031) 0.031 (0.026‑0.037) 0.039 (0.032‑0.047) 0.046 (0.037‑0.055) 0.055 (0.043‑0.069) 0.062 (0.048‑0.078) 0.070 (0.052‑0.090) 0.078 (0.054‑0.102) 0.091 (0.061‑0.122) 0.102 (0.066‑0.139) 10-day 0.021 (0.018‑0.025) 0.025 (0.021‑0.030) 0.031 (0.025‑0.037) 0.036 (0.029‑0.043) 0.043 (0.033‑0.053) 0.048 (0.037‑0.060) 0.053 (0.039‑0.068) 0.059 (0.041‑0.077) 0.068 (0.046‑0.091) 0.076 (0.049‑0.103) 20-day 0.015 (0.012‑0.018) 0.017 (0.014‑0.020) 0.020 (0.017‑0.024) 0.023 (0.019‑0.027) 0.026 (0.021‑0.032) 0.029 (0.022‑0.036) 0.032 (0.024‑0.040) 0.035 (0.024‑0.045) 0.039 (0.026‑0.051) 0.042 (0.027‑0.056) 30-day 0.012 (0.010‑0.015) 0.014 (0.011‑0.016) 0.016 (0.013‑0.019) 0.018 (0.015‑0.021) 0.020 (0.016‑0.024) 0.022 (0.017‑0.027) 0.024 (0.018‑0.030) 0.026 (0.018‑0.033) 0.028 (0.019‑0.037) 0.030 (0.020‑0.040) 45-day 0.010 (0.009‑0.012) 0.011 (0.009‑0.013) 0.013 (0.011‑0.015) 0.014 (0.012‑0.016) 0.016 (0.012‑0.019) 0.017 (0.013‑0.021) 0.018 (0.013‑0.023) 0.020 (0.014‑0.025) 0.021 (0.014‑0.027) 0.022 (0.014‑0.029) 60-day 0.009 (0.007‑0.010) 0.010 (0.008‑0.011) 0.011 (0.009‑0.013) 0.012 (0.010‑0.014) 0.013 (0.010‑0.016) 0.014 (0.011‑0.017) 0.015 (0.011‑0.019) 0.016 (0.011‑0.021) 0.017 (0.011‑0.022) 0.018 (0.012‑0.023) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (fora given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are notchecked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical 10/1/24, 11:49 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=41.4530&lon=-72.1399&data=intensity&units=english&series=pds 1/4 Back to Top Maps & aerials Small scale terrain 10/1/24, 11:49 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=41.4530&lon=-72.1399&data=intensity&units=english&series=pds 2/4 Large scale terrain Large scale map Large scale aerial + – 3km 2mi + – 100km 60mi + – 100km 60mi 10/1/24, 11:49 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=41.4530&lon=-72.1399&data=intensity&units=english&series=pds 3/4 Back to Top US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service National Water Center 1325 East West Highway Silver Spring, MD 20910 Questions?: HDSC.Questions@noaa.gov Disclaimer + – 100km 60mi 10/1/24, 11:49 AM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=41.4530&lon=-72.1399&data=intensity&units=english&series=pds 4/4 CLA Engineers, Inc. Civil · Structural · Survey Appendix D StreamStats Report StreamStats Report Collapse All Basin Characteristics Parameter Code Parameter Description Value Unit DRNAREA Area that drains to a point on a stream 9.66 square miles I24H100Y Maximum 24-hour precipitation that occurs on average once in 100 years 7.79 inches I24H10Y Maximum 24-hour precipitation that occurs on average once in 10 years 5.07 inches I24H200Y Maximum 24-hour precipitation that occurs on average once in 200 years 8.89 inches I24H25Y Maximum 24-hour precipitation that occurs on average once in 25 years 6.15 inches I24H2Y Maximum 24-hour precipitation that occurs on average once in 2 years - Equivalent to precipitation intensity index 3.16 inches I24H500Y Maximum 24-hour precipitation that occurs on average once in 500 years 10.34 inches I24H50Y Maximum 24-hour precipitation that occurs on average once in 50 years 6.97 inches I24H5Y Maximum 24-hour precipitation that occurs on average once in 5 years 4.25 inches SSURGOCCDD Percentage of area with hydrologic soil types C, D, or C/D from SSURGO 0.3108 percent Region ID:CT Workspace ID:CT20241205180712767000 Clicked Point (Latitude, Longitude):41.45263, -72.13696 Time:2024-12-05 13:07:40 -0500   12/5/24, 1:09 PM StreamStats https://streamstats.usgs.gov/ss/1/3 Peak-Flow Statistics Peak-Flow Statistics Parameters [Statewide DA only SIR 2020 5054] Parameter Code Parameter Name Value Units Min Limit Max Limit DRNAREA Drainage Area 9.66 square miles 0.69 325 Peak-Flow Statistics Parameters [Statewide Multiparameter SIR 2020 5054] Parameter Code Parameter Name Value Units Min Limit Max Limit DRNAREA Drainage Area 9.66 square miles 0.69 325 I24H2Y 24 Hour 2 Year Precipitation 3.16 inches 2.77 3.32 SSURGOCCDD Percent soil type C or D from SSURGO 0.3108 percent 0.118 0.945 I24H5Y 24 Hour 5 Year Precipitation 4.25 inches 4 4.7 I24H10Y 24 Hour 10 Year Precipitation 5.07 inches 4.86 5.79 I24H25Y 24 Hour 25 Year Precipitation 6.15 inches 5.99 7.22 I24H50Y 24 Hour 50 Year Precipitation 6.97 inches 6.81 8.3 I24H100Y 24 Hour 100 Year Precipitation 7.79 inches 7.62 9.38 I24H200Y 24 Hour 200 YearPrecipitation 8.89 inches 8.7 11.22 I24H500Y 24 Hour 500 Year Precipitation 10.34 inches 10.1 13.64 Peak-Flow Statistics Flow Report [Statewide DA only SIR 2020 5054] PIL: Lower 90% Prediction Interval, PIU: Upper 90% Prediction Interval, ASEp: Average Standard Error of Prediction, SE: Standard Error, PC: Percent Correct, RMSE: Root Mean Squared Error, PseudoR^2: Pseudo R Squared (other -- see report) Statistic Value Unit ASEp Drainage Area Only 50-percent AEP flood 374 ft^3/s 35 Drainage Area Only 20-percent AEP flood 645 ft^3/s 35 Drainage Area Only 10-percent AEP flood 870 ft^3/s 36.3 Drainage Area Only 4-percent AEP flood 1210 ft^3/s 37.8 Drainage Area Only 2-percent AEP flood 1490 ft^3/s 39.8 Drainage Area Only 1-percent AEP flood 1810 ft^3/s 42.4 Drainage Area Only 0.5-percent AEP flood 2180 ft^3/s 44.4 Drainage Area Only 0.2-percent AEP flood 2720 ft^3/s 48 Peak-Flow Statistics Flow Report [Statewide Multiparameter SIR 2020 5054] PIL: Lower 90% Prediction Interval, PIU: Upper 90% Prediction Interval, ASEp: Average Standard Error of Prediction, SE: Standard Error, PC: Percent Correct, RMSE: Root Mean Squared Error, PseudoR^2: Pseudo R Squared (other -- see report) Statistic Value Unit PIL PIU ASEp 50-percent AEP flood 326 ft^3/s 80 1330 26.5 20-percent AEP flood 488 ft^3/s 109 2190 26.3 10-percent AEP flood 608 ft^3/s 125 2950 28.4 4-percent AEP flood 805 ft^3/s 150 4320 31.5 2-percent AEP flood 978 ft^3/s 166 5760 34.3 1-percent AEP flood 1170 ft^3/s 181 7580 37.1 0.5-percent AEP flood 1380 ft^3/s 241 7890 40.6  12/5/24, 1:09 PM StreamStats https://streamstats.usgs.gov/ss/2/3 Statistic Value Unit PIL PIU ASEp 0.2-percent AEP flood 1730 ft^3/s 323 9270 45 Peak-Flow Statistics Flow Report [Area-Averaged] PIL: Lower 90% Prediction Interval, PIU: Upper 90% Prediction Interval, ASEp: Average Standard Error of Prediction, SE: Standard Error, PC: Percent Correct, RMSE: Root Mean Squared Error, PseudoR^2: Pseudo R Squared (other -- see report) Statistic Value Unit ASEp Drainage Area Only 50-percent AEP flood 374 ft^3/s 35 Drainage Area Only 20-percent AEP flood 645 ft^3/s 35 Drainage Area Only 10-percent AEP flood 870 ft^3/s 36.3 Drainage Area Only 4-percent AEP flood 1210 ft^3/s 37.8 Drainage Area Only 2-percent AEP flood 1490 ft^3/s 39.8 Drainage Area Only 1-percent AEP flood 1810 ft^3/s 42.4 Drainage Area Only 0.5-percent AEP flood 2180 ft^3/s 44.4 Drainage Area Only 0.2-percent AEP flood 2720 ft^3/s 48 50-percent AEP flood 326 ft^3/s 80 1330 26.5 20-percent AEP flood 488 ft^3/s 109 2190 26.3 10-percent AEP flood 608 ft^3/s 125 2950 28.4 4-percent AEP flood 805 ft^3/s 150 4320 31.5 2-percent AEP flood 978 ft^3/s 166 5760 34.3 1-percent AEP flood 1170 ft^3/s 181 7580 37.1 0.5-percent AEP flood 1380 ft^3/s 241 7890 40.6 0.2-percent AEP flood 1730 ft^3/s 323 9270 45 Peak-Flow Statistics Citations Ahearn, E.A., and Hodgkins, G.A.,2020, Estimating flood magnitude and frequency on streams and rivers in Connecticut, based on data through water year 2015: U.S. Geological Survey Scientific Investigations Report 2020–5054, 42 p. (https://doi.org/10.3133/sir20205054) USGS Data Disclaimer: Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. USGS Software Disclaimer: This software has been approved for release by the U.S. Geological Survey (USGS). Although the software has been subjected to rigorous review, the USGS reserves the right to update the software as needed pursuant to further analysis and review. No warranty, expressed or implied, is made by the USGS or the U.S. Government as to the functionality of the software and related material nor shall the fact of release constitute any such warranty. Furthermore, the software is released on condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from its authorized or unauthorized use. USGS Product Names Disclaimer: Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Application Version: 4.24.0 StreamStats Services Version: 1.2.22 NSS Services Version: 2.2.1 12/5/24, 1:09 PM StreamStats https://streamstats.usgs.gov/ss/3/3