HomeMy Public PortalAbout333028etropolitan
St. Louis Sewer
District
2350 Market Street
St. Louis, MO 63103-2555
(314) 768-6200
December 15, 2008
Mr. Brad Gianotti
Regulatory Compliance Coordinator
BaySaver Technologies, Inc.
1302 Rising Ridge Road
Mount Airy, MD 21771
RE: Baysaver Technologies BaySeparator: St. Louis MSD Submission
Redevelopment Use Level (RUL) Approval within District
Dear Sir:
The Metropolitan St. Louis Sewer District (MSD) has reviewed your application regarding the
BaySeparator for use as a Best Management Practice for stormwater management. MSD is
pleased to provide Redevelopment Use Level (RUL) approval for use of the BaySeparator as a
stand-alone water quality BMP, subject to the following provisions.
® The BaySeparator is only approved for use on redevelopment sites less than 5 acres. This
approval is based on compliance with requirements listed in MSD's Proprietary Water
Quality Products and the MSD's Stormwater Management Program (Jan. 2008).
The BaySeparator must be sized to capture all floatable trash and free oil, and remove
80% of total suspended solids for the OK-1 10 particle size distribution at the site water
quality flow -rate (WQr). Procedures for calculating WQt are provided in Appendix D.10
of the Maryland Stormwater Design Manual (2000). Table 1 provides a list of approved
models and their respective instantaneous peak treatment WQ,-.
Table : BaySeparator Approved Models and Peak W
System Model
Primary & Secondary Manhole
Max Treatment Flow
(cfs)
Depth (feet)
Diameter (feet)
1/4 K
6
4
0.24
1K
8
4
0.3
3K
8
5
1.0
5K
8
6
2.0
1 OK
8
10
3.7
The primary and secondary manhole, as well as the Baysaver unit, should be configured
in an off-line layout. In most cases the BMP will be installed without the need to store
the water quality volume (WQ,;) upstream of the unit.
All devices shall provide a minimum sediment storage capacity of 10 ft3.
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E n g i n e e r i n g / D e s i g n
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