What is Your NPDES Compliance Criteria?

Typical Street Right-of-way for: ClearWater BMP Treatment Capacity*
Rainfall Intensity, Inches/Hr
0.20 0.25 0.50 0.75
R.O.W.Treatment Capacity, Acres
2.5 2.0 1.0 0.67
*treatment capacity = 200 gpm before flow bypassing occurs .46 cfs
ClearWater BMP
Design Consideration
Feature Specifications Benefits
Targeting Urban Retrofit and New Development:Impervious surface runoff capture and treatment area equivalent . Filters up to 1.5" of rain per hour. At .50" of rain per hour unit can handle 43,560 square feet of drainage (1 acre). Conserves land for other uses; optimizes land use where space is at a premium, e.g., urban retrofit.
Flow Thru Design Limits:
Continuous flow-thru design limit 200 gpm (based on a 5/8" weir opening) Exceeds NPDES criteria for "first flush".
Overflow flow-thru to flood system 250 gpm (based on a ¾" weir opening) No clogging of stormdrains.
Primary Chamber Capacity Coarse Settling
5.5 cf capacity
Cover and Back-panel Baffle ensures that it never scours/re-suspends sediments.
Secondary Chamber Capacity Fine Settling ¾" to 5/8" submerged neck-down between chambers ensures stilling and sedimentation
Final Chamber Soluable Filtering Soluable Filtration including Bacteria.
Filter Media:
  • Perlite-zeolite
  • mix
  • AbTec panel smart sponge (option)
  • Rubberizer oil-sock
  • Fish Filter pad
  • Metals,
  • emulsified hydrocarbons, organics (chlorine, ammonia)
  • Pathogens
  • Floating
  • hydrocarbons
  • Larger diameter suspended
  • solids
  • Pollution reduction at/near the source.
  • Removal efficiencies:
    97% TSS, 86% Oil and Grease (O&G), 81% for lead (Pb), 83% for Zinc (Zn).
  • Satisfactory rates for heavy metals in solution.
Maintenance Requirements:
  • Filter media
  • Sediment removal
As required. Can be done from the curb using shop vac and generator or pumper truck. Does not require sophisticated system. Is accessed from the curb.
Fabrication Materials .304 gauge stainless steel, 16 GA Won't corrode.
Outside Dimensions 30" wide; 30" high at rear-tapers to 20" at front, 34" front to back including trash hoops and nets.
Assembly Assembles inside existing drain box. Can be retrofitted to older systems if box is large enough. Narrower Model is available.
Mosquito Free Self-draining Presents no health hazard.
Water Capture: 100% (at 200 gpm with 5/8" weir opening) Design brings all water through the system; water tight seals between wall of drain box and filter. Treats all water; captures all trash.