HomeMy Public PortalAboutPaveDrain_LetterMetropolitan
St. Louis Sewer
District
2350 Market Street
St. Louis, MO 63103-2555
(314) 768-6200
www.stlmsd.com
July 25, 2012
Mr. Dave Schuster
ASP Enterprises
1099 Cassens Industrial Ct.
Fenton, MO 63026
RE: Pavedrain Articulating Permeable Paving Surface - A Structural BMP
Dear Mr. Schuster,
The Metropolitan St. Louis Sewer District (MSD) has reviewed your application of the
Pavedrain Articulating Permeable Paving Surface and hereby grants the product Provisional Use
Level (PUL) approval. MSD understands that Pavedrain is an articulating concrete block mat
system that enhances surface permeability by the open space created between the blocks.
Pavedrain is recognized as a permeable pavement in satisfying MSD stormwater management
requirements.
MSD has determined that Pavedrain may be used under the following conditions:
1. Proposed uses and designs of Pavedrain, must be in general conformance with the
information and methodologies provided by ASP Enterprises and PaveDrain LLC
received March 28, 2012 and the detail attached to this approval letter.
2. Channel Protection Volume (CPv) storage may be provided in the sub base stone beneath
the articulating block and bedding layer.
3. The articulating block mat shall rest on a 4-inch thick layer of base stone (ASTM No. 57
or similar size), and a layer of subbase stone (ASTM No. 2 or similar size), all underlain
by MSD type 4 filter fabric. The thickness of the subbase will vary depending on storage
and anticipated traffic loads. However, a minimum 12-inch thick subbase will be required
for all applications.
4. The post -developed curve number (CN) for the footprint of the Pavedrain Articulating
Permeable Paving Surface may be reduced. Reduced CN numbers are provided below.
Soil A B C D
CN 61 61 74 80
5. The Pavedrain system will be considered as pervious area for the purpose of calculating
Water Quality Volume (WQv) and 5 percent impervious when calculating the differential
runoff with PI factors. However, the Pavedrain will be considered as 100 percent
impervious area for the purpose of calculating pipe sizes downstream and when
evaluating a site's annual post developed runoff condition.
6. Pavedrain may be considered as a stand-alone BMP in certain design instances. Those
designs are subject to MSD review and approval.
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7. Project specific design calculations and maintenance plans must be included within the
project's "Stormwater Management Facilities Report" prepared by the consulting
Engineer.
MSD reserves the ability to withdraw or modify this approval based on subsequent information,
including information indicating that Pavedrain does not satisfy MSD rules, requirements, or
construction and material specifications. Please provide MSD with a representative sample of the
product your supplying manufacturer is producing.
Sincerely,
Jason T. Peterein, P.E.
Civil Engineer (BMP Committee Chairman)
Engineering / Planning / Development Review
Metropolitan St. Louis Sewer District
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LOW SLUMP
CLASS "A" CONC.
P—ACB/M JOINTS TO
BE FILLED WITH MSD
APPROVED MATERIAL.
4" OPEN GRADED BASE -
(ASTM NO. 57)
8-12" SUB BASE -
(THICKNESS VARIES)
(ASTM NO. 2)
CAST IRON FRAME & LID.
NEENAH FOUNDRY R-1975—A
OR APPROVED EQUAL
(TYP)
6" (TYP)
6" (TYP)
6" PERFORATED
SCHEDULE 40 PVC
OBSERVATION WELL
DETAIL
OBSERVATION WELL
P—ACB/M SURFACE
CURB EDGE
(OPTIONAL)
WITH CUTS
FOR OVERFLOW
v •
•
a ; • \\\�j��
APPROVED
GEOTEXTILE
UNDERDRAIN (PERCHED OPTIONAL*)
4" TO 6" PERFORATED RIGID
SCHEDULE 40 PVC OR SDR 35.
3/8" PERFORATED ON 12" CENTERS, 2 ROWS,
5 AND 7 O'CLOCK RESPECTIVELY.
PERMEABLE - ARTICULATING CONCRETE BLOCK/MAT
TYPICAL SECTION
* THE NEED FOR A PERCHED UNDERDRAIN IS OPTIONAL AND IS
DEPENDENT ON THE INFILTRATION RATE OF THE SUBGRADE SOIL.
PLASTIC SOILS SHOULD NOT PERCH THE UNDERDRAIN. THE
HORIZONTAL AND VERTICAL LOCATION OF ALL UNDERDRAINS SHALL
BE DETERMI ED BY THE ENGINEER, AND SHOWN ON THE PLANS.
* ADDITIONAL UNDERDRAINS MAY BE PERCHED ABOVE THE
REQUIRED STORAGE ELEVATION AND WITHIN THE STORAGE
BED IN ORDER TO PROTECT THE PAVER BLOCKS FROM
UP FLOWS RESULTING FROM SURCHARGE.
PAVEDRAIN
STANDARD DETAIL.
OBSERVATION WEI J.
CROSS-SECTION
4880 W. ABBOTT AVE.
GREENFIELD, WI. 53220
(4I4) 423-(,531
\C" W.EA\'I•:DRAIN,C0�I
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