HomeMy WebLinkAboutStormwater Management - COM Letters / Memos - 4/20/1994 GARY YANDO,DIRECTOR
Py�N.STgT�O
c A o u DEPARTMENT OF COMMUNITY DEVELOPMENT
_
r a T z PLANNING-SOLID WASTE.-UTILITIES
z� N Y y BLDG.III • 426 W.CEDAR• P.O.BOX
1864 578
SHELTON,WA 98584 • (206)427=9670
-
April 20, 1994
Cascade Floral Products
PO Box 1299
Belfair, WA 98528
Please reference the accompanying enclosed document regarding stormwater management. We
are unable to further process your building permit application until we receive the information
requested. t'
Respec�tfull
anassee, Planner
ZJ�Dlnartment
of Community Development
c:
Me
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GARY YANDO,DMECTOR
PyON.STgTFo
o A° N u DEPARTMENT OF COMMUNITY DEVELOPMENT
o T i PLANNING-SOLID WASTE-UTI11=S
i� N Y y BLDG.III •_426 W.CEDAR • P.O.BOX 578
of 1864 `'o SHELTON;WA 98584 • (206)427-9670'
STORMWATER MANAGE TENT GUIDELINES
Mason County,requires development of this type to meet the following minimum standards
for the management of storm water:
4.2 Runoff Quantity ;
All proposed projects must provide runoff quantity controls to achieve the,following three
purposes unless exempted because of direct..discharge to a regional facility or a:major body of
water or because of negligible increase in runoff( see 4.2.1, below)
1. Infiltrate at least the excess runoff volume generated by the proposed development for
the 2-year , 24-hour design storm, provided that site conditions are appropriate and
ground water quality will not be impaired. Release any residual runoff from the 2-year,
24-hour design storm at no greater than 100% of the peak runoff rate for that storm for `
existing site conditions.
2. If infiltration is precluded because of site conditions then detain and release runoff from
the 2-year,24-hour design storm at no greater than 50% of the peak runoff rate for pre-
existing site conditions.
3. Detain and release runoff from the 10 and 100-year, 24-hour design storm at no greater
than 100% of the peak rate for existing site conditions.
Your submitted drainage report should-include at a minimum, a site plan showing topographic
lines, facility design and supporting calculations. All site preparation .should be done in
accordance with Best Management Practices as outlined in the Stormwater Management Manual
for the Puget Sound Basin.
If you have specific questions about stormwater facility design please contact Alan Tahja of the
Mason County Public Works Department. Please submit your plans to the address below,
ATTN J. Manassee.
i
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