HomeMy WebLinkAboutZoning Officer's Report - Stormwater Management Dec 13, 2006.PDFSttlury uf 6ugug a Htights
MARCHAM HALL
836 HANSHAW ROAD
ITHACA, N.Y.14850
ZONING OFFICER'S REPORT
December 13,2006
PLANNING BOARD
Brent A. Cross, Zoning Officer
Stormwater Management
ln anticipation of the upcoming review of the upland Roa{ SuMivision project, I would like to
explain the Planning Boards r6le in making sure that the developer does not build a project that
will aggravate tne e*sti;g;t"in"g"conditions on.this:tt". At l result of the EPA Phase ll
stormwater Regulations, the NYSDEG has established a permit known has the state Pollutant
Discharge Elimination SYstem.
Such a pennit is required on all projects that exceed one acre of "disturbed" land' lt is a two part
permit, that requires ifre aeveloierio provlCe soil erosion and sedimentation controls during the
construction process as well as quality and quantity control of stormwater after construction is
completed.
The first part, which deals with construction, usually requires the developer to provide temporary
improvements Such "i "ift
tences and sediment ponds.'These are common construc*ion features
and developers are usually familiar with the use of them'
The second part of the pennit deals with the stormwater quantity and quality from the site after
full ,,build-out". The Oasic directive is as follows: The developer shall provide drainage controls
(such as detention n"iini that will lim,itthe rate of stormwater run-off from the developed site to
be no more that the amount of run-off from the existing site. This usually results.in-a pond that
fills up during storm events and the water is then allowed to drain out over a period of time
thrcugh a control struGture that limits the rate of flow' This feature accomplishes the quantity
controls component of the permit. The permit also requires quality control' which is. usually
provided through tne use o? a "forebay'; fot tuttling oui solids and a wet pool in the bottom of the
ilond to ac't as I buffer for other dissolved contaminants'
Although the design specifications require the developer to size the stormwater management
facilities to handle a i"ng" of storms from the 2-year storm event up to the loGyear event, no
two storms are the ,"mei. Therefore, it is not poisible to com.pletely eliminate the possibility of
downstream 1ooOing, but engineers'h"u* "#utulated
a wide range of data sets that are used
as the basis for the calculations to provide the level of 'best management practices"'
As a reminder, the Village has been designated a Municipal Separate Storm S"Ygi System
(MS4) as part of the gr;;ier metro lthaca"community' This designation requires MS4's to adopt
local regulations that"effectively assume the enactment and enforcement of such stormwater
regulations at the local level.
Telephone
@7-257-1238
Offics Hours
9A.M.-4P.M.
DrITE:
Ttf,:
FIR,OM:
RE:
REPORT:
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