Comparative Pollutant Removal of Urban BMP Designs Reducing the Impacts of Stormwater Runoff from New Development; New York State Department of Environmental Conservation. April 1992.
Figure 15.
Design 1:
First-flush runoff volume detained for six to 12 hours.
Design 2:
Runoff volume produced by 1.0 inch, detained 24 hours.
Design 3:
As in Design 2, but with shallow marsh in bottom stage.
Design 4:
Permanent pool equal to 0.5 inch storage per impervious acre.
Design 5:
Permanent pool equal to 2.5 (V7); where V7=mean storm runoff.
Design 6:
Permanent pool equal to 4.0 (V7); approx. two weeks' retention.
Design 7:
Facility exfiltrates first-flush; 0.5 inch runoff per impervious acre.
Design 8:
Facility exfiltrates one inch runoff volume per impervious acre.
Design 9:
Facility exfiltrates all runoff, up to the two-year design storm.
Design 10:
400 cubic feet wet storage per impervious acre.
Design 11:
20-foot-wide turf strip.
Design 12:
100-foot-wide forested strip, with level spreader.
Design 13:
High-slope swales, with no check dams.
Design 14:
Low-gradient swales with check dams.
Source: M.W.C.G., "Controlling Urban Runoff"
Rainfall Intensity Curves
Lake George, New York
Ref: U.S. Weather Bureau Technical Paper No. 40, May 1961 (HDM #26) National Oceanic and Atmospheric Administration Technical Memorandum NWS Hydro 35, June 1977 (HDM #27)
Sample Stormwater Control Facility Maintenance Agreement
WHEREAS, the VILLAGE OF LAKE GEORGE ("VILLAGE") and the ___________________ ("FACILITY OWNER") want to enter into an agreement to provide for the long-term maintenance and continuation of stormwater control measures approved by the VILLAGE for the below-named project, and
WHEREAS, the VILLAGE and the FACILITY OWNER desire that the stormwater control measures be built in accordance with the approved project plans and thereafter be maintained, cleaned, repaired, replaced and continued in perpetuity in order to ensure optimum performance of the components. Therefore, the VILLAGE and the FACILITY OWNER agree as follows:
1.
This agreement binds the VILLAGE and the FACILITY OWNER, its successors and assigns, to the maintenance provisions depicted in the approved project plans which are attached as Schedule A of this agreement.
2.
The FACILITY OWNER shall maintain, clean, repair, replace and continue the stormwater control measures depicted in Schedule A as necessary to ensure optimum performance of the measures to design specifications. The stormwater control measures shall include, but shall not be limited to, the following: drainage ditches, swales, dry wells, infiltrators, drop inlets, pipes, culverts, soil absorption devices and retention ponds.
3.
The FACILITY OWNER shall be responsible for all expenses related to the maintenance of the stormwater control measures and shall establish a means for the collection and distribution of expenses among parties for any commonly owned facilities.
4.
The FACILITY OWNER shall provide for the periodic inspection of the stormwater control measures, not less than once in every five-year period, to determine the condition and integrity of the measures. Such inspection shall be performed by a professional engineer licensed by the State of New York. The inspecting engineer shall prepare and submit to the VILLAGE within 30 days of the inspection a written report of the findings, including recommendations for those actions necessary for the continuation of the stormwater control measures.
5.
The FACILITY OWNER shall not authorize, undertake or permit alteration, abandonment, modification or discontinuation of the stormwater control measures except in accordance with written approval of the VILLAGE.
6.
The FACILITY OWNER shall undertake necessary repairs and replacement of the stormwater control measures at the direction of the VILLAGE or in accordance with the recommendations of the inspecting engineer.
7.
The FACILITY OWNER shall provide to the VILLAGE within 30 days of the date of this agreement a security for the maintenance and continuation of the stormwater control measures in the form of a bond, letter of credit or escrow account.
8.
This agreement shall be recorded in the Office of the County Clerk, County of Warren, together with the deed for the common property and shall be included in the offering plan and/or prospectus approved pursuant to __________________________.
9.
If ever the VILLAGE determines that the FACILITY OWNER has failed to construct or maintain the stormwater control measures in accordance with the project plan or has failed to undertake corrective action specified by the VILLAGE or by the inspecting engineer, the VILLAGE is authorized to undertake such steps as reasonably necessary for the preservation, continuation or maintenance of the stormwater control measures and to affix the expenses thereof as a lien against the property.
10.
This agreement is effective ______________.
VILLAGE OF LAKE GEORGE
By
By