21094_Town Engineer Response
38 High Rock Ave, Suite 3 | P.O. Box 272 | Saratoga Springs, NY 12866 | 518.450.4030
July 15, 2022
Mr. Craig Brown
Zoning Administrator and Code Compliance Officer
Town of Queensbury
742 Bay Road
Queensbury, New York 12804
Re: Foothills Builders Apartments
Town of Queensbury, Warren County, New York
Queensbury Ref #SP27-2022
Dear Mr. Brown,
We are in receipt of The LaBella review letter, dated May 23, 2022, pertaining to the above
referenced project located in the Town of Queensbury, NY. With respect to the comments
provided in the above referenced Town Engineer letter, please see the following responses:
Regarding Comment No. 2:
A 50-year storm analysis has been provided for the proposed development and results
demonstrate that the proposed stormwater system attenuates runoff rates and volumes to be
equal to or less than existing conditions.
Regarding Comment No. 3:
Offsite tributary areas were evaluated to determine appropriate boundaries of tributary areas to
the project site. Based on existing topography and development, it is our opinion that the
subcatchment boundaries shown on the current subcatchment plans are accurate and include
applicable tributary areas.
Regarding Comment No. 4:
Additional test pits can be conducted at the request of the Town to verify that required
separation from restrictive layers is achieved.
Results of the four test pits completed at the site indicate that in-situ soils are uniform across the
site area and consist of poorly graded sand. These results are also consistent with those provided
in the USDA soil survey. As such, it is our opinion that the infiltration tests completed at the site
are sufficient and represent accurate infiltration rates of the in-situ material and further tests are
not required to evaluate infiltration within the area proposed for stormwater control practices.
Regarding Comment No. 5:
The quantity and layout of the proposed infiltrator system is provided on construction drawing C-
3.10, Utilities Plan, and in detail #2 on construction drawing C-5.11. Additionally, details regarding
the quantity of the infiltrator system are provided in the HydroCAD report for post-construction
conditions via the chamber wizard tool that is available for the specified infiltrator units.
Regarding Comment No. 6:
The plans and stormwater calculations have been updated to include pretreatment via an isolator
row. The revised plans and stormwater calculations are provided as attachments enclosed with
this letter.
Regarding Comment No. 7:
The 10” dia. orifice included as an outlet device as a conservative check to evaluate the behavior
of stored runoff during the 50-year storm analysis and confirm that runoff is exfiltrating through
the stone base and not returning to the catch basin via the distribution manifold. The orifice
invert elevation is set at 494.0’ to mimic the inlet invert elevation to the infiltrator system
Regarding Comment No. 8:
The proposed infiltration practices, including infiltrator chambers will be installed beneath the
proposed parking lot area within an excavated void. Therefore, it is not feasible to protect the
area above the proposed location of the infiltrator chamber system throughout the duration of
construction considering the nature of proposed development. Further, appropriate maintenance
measures will be applied to the catch basin inlets and storm pipe to prevent the accumulation of
sediment proceeding installation.
Regarding Comment No. 9:
Drawing C-0.20 has been revised to include enhanced erosion and sediment control measures for
construction activities occurring between November 15th and April 1st.
Please find the following attachments enclosed:
- Revised Stormwater Management Narrative, dated July 12, 2022
- Revised Construction Drawings
If you have any questions, please contact the undersigned at (518) 450-4030.
Sincerely,
Matthew E. Huntington, PE
Principal
For
Studio A | Landscape Architecture + Engineering