HomeMy WebLinkAboutTE COMMENTS 8-24-2010ril
Jacobson
Mr. Thomas Sanders
Re: Lots #28 and 438
Thomas Avenue
Site Plan Review
NLJ #0809-0157
August 23, 2010
Page 2
the site design should confirm that regrading and redirecting of surface runoff will not impact
the private road or adjacent properties.
2. The plans show yard drains on each lot with top of structure 0.5 feet above the pipe invert.
These elevations indicate that there will be little or no cover over the pipe at the structure
location.
3. Design details and elevations should be provided for the stormwater infiltration trenches. It
should be confirmed that a minimum of one foot of cover will be provided.
4. Drainage calculations and the basis of design for the stormwater infiltration trenches should be
provided. In would appear, due to the location of the trenches immediately adjacent to the
property lines, that in larger storm events, should flows exceed capacity, adjacent properties
could be impacted.
5. Since soils on the lots are characterized by high groundwater conditions, it should be
confirmed that the stormwater infiltration trenches will be above seasonally high groundwater
levels.
6. We would question how maintenance of the stormwater infiltrators will be enforced should the
systems be compromised and adjacent properties impacted.
Should you have any questions, please do not hesitate to contact me.
Very truly yours,
NATHAN L. JACOBSON & ASSOCIATES, INC.
omas H. Fenton, P.E.
THF:thf'
cc: Hon. Joseph W. Jaskiewicz
Donald W. Bourdeau, Jr.
Towne Engineering, Inc.
Jacobson
Mr. Thomas Sanders
Assistant Planner
Town of Montville
310 Norwich -New London Turnpike
Uncasville, Connecticut 06382-2599
Re: Lots #28 and #38
Thomas Avenue
Site Plan Review
NLJ #0809-0157
Dear Mr. Sanders
August 24, 2010
As requested, we have reviewed the following information received for the subject project at our
office through August 17, 2010:
Item 1: Drawing entitled "Septic System Design prepared for Tony Morizio; Lot #28, Thomas
Ave., Montville, Connecticut', scale I"=20% dated 10/15/2008 and last revised 5/I/09,
prepared by Towne Engineering, Inc.
Item 2: Drawing entitled "Septic System Design prepared for Tony Morizio, Lot #38, Thomas
Ave., Montville, Connecticut', scale 1"=20% dated 10/15/2008 and last revised 5/1/09,
prepared by Towne Engineering, Inc.
The above referenced plans provide septic system designs for two individual lots fronting on Thomas
Avenue, a private road extending easterly from Connecticut Route 32. Both lots are proposed to
have individual; on site wells and septic systems. The lots are relatively small and soil testing
indicates high ground water conditions which requires fill to construct the septic systems. The
Uncas Health District has reviewed the septic system design. Our engineering review, therefore,
focuses on the aspects of site grading and control of stormwater runoff associated with the projects.
We have the following comments
Although existing contours shown on the submitted plans extend only minimally offsite, it
appears that topography in the area slopes generally west to east and surface runoff currently
flows as sheet flow across the lots. The proposed plan will change surface drainage patterns
due to fill placed to support the septic system design. Surface runoff and roof drains will be
conveyed via swales and yard drains to proposed stormwater infiltration trenches on the
southeast corner of Lot 428 and the northeast corner of Lot #38. As further discussed below,
Nathan L Jacobson & Associates, Inc.
Nathan L. Jacobson & Associates, P.C. (NY)
86 Main Street P.O. Box 337 Chester, Connecticut 06412-0337
Tel 860.526.9691 Fax 860.526.5416
Consulting Civil and Environmental Engineers Since 1972