HomeMy WebLinkAboutConsultant Review - 880 GREAT POND ROAD 3/12/2008 RECEIVED
Eggleston E'nvironmentq4A R 12 700
NORTH H'�uUVER
PLANNING DEPARTMENT
March 12, 2008
North Andover Conservation Commission RECEIVED
1600 Osgood Street Building 20, Suite 2-36 0tq�
North Andover, MA 01845 MAR 12 2008
RE: Stormwater Management Review NORTH ANDOVER
880 Great Pond Road, Crusader Paper Company CONSERVATION COMMISSION
Dear Commission Members:
Per your request, I have conducted an initial technical review of the proposed
development at 880 Great Pond Road in North Andover with respect to stormwater
management. The materials I have received and reviewed to date include the following:
• Plan Showing Proposed Dwelling (Site Plan), 880 Great Pond Road, North
Andover, MA. Prepared by Andover Consultants, Inc. and dated December 3,
2007, revised March 5, 2008.
• Landscape Plan, 880 Great Pond Road, North Andover MA. Prepared by
Weinmayr-Jay Associates, Inc. and dated March 5,2008.
I also conducted a brief visit to the site this morning to observe existing conditions.
It is my understanding that, due to its size, this project is not subject to the requirements
of the stormwater management and flood storage standards (Section IV) of the North
Andover Wetlands Bylaw or the Massachusetts Wetlands Protection Act and Stormwater
Management Policy. 1 have therefore focused my comments on the overall stormwater
management concept for the site, the proposed drainage system design, and potential
hydrologic impacts to wetland resources. My comments are outlined below:
1. The proposed project does discharge within a critical area, the Lake
Cochichewick watershed area, and nearly all of the proposed development is
within the 250-foot non-disturbance zone to the reservoir. The project should
therefore be held to the highest standards with regard to stormwater management.
2. No runoff calculations have been submitted comparing predevelopment runoff
flows to post-development conditions. Preservation of existing drainageways also
needs to be addressed.
3. As proposed, the flow from impervious surfaces on the site (the roof and semi-
pervious driveway areas) will be directed to three subsurface infiltration trench
systems. However, the infiltration systems appear to have been sized to store only
0.5 inches of runoff from these surfaces, e.g. the water quality volume. There is
55 Otd Coach Road Sudbury NA 01776 cel 508.259.1137 fax 866.820.7840
880 Great Pond Road, Technical Reviex 2
h4,iivh I2, 2008
no indication of where overflow from the systems will occur, and what impact the
increased rate of runoff might have on adjacent resource areas. It is also not clear
from the plans how the roof area is being distributed among the three infiltration
systems.
4. Site specific soil testing data is needed to confirm the soil type, depth to
groundwater, depth to bedrock, and storage capacity at the proposed stormwater
infiltration system locations.
5. No detail is provided for the proposed catchbasin.
6. Given its sensitive location, more detail is needed on the proposed erosion and
sediment control measures to be undertaken during construction.
7. Ongoing maintenance of the proposed drainage structures should be addressed.
8. The site plan is incorrectly shown as having a scale of 1"=800'. I believe the
correct scale is 1"=20'. The plan should also be signed and stamped by a
registered professional engineer.
I appreciate the opportunity to assist the North Andover Conservation Commission with
the review of this project, and hope that this information is suitable for your needs. Please
feel free to contact me if you or the applicants have any questions regarding the issues
addressed herein.
Sincerely,
EGGLESTON ENVIRONMENTAL
Lisa D. Eggleston, P.E.