When a large residential development wanted to incorporate decentralized water quality treatment, there were a number of issues associated with designing and delivering the right solution:
- Over sixty inlets needed decentralized inlet treatment inserts.
- Water quality volume needed PADEP recognized water quality treatment prior to discharge off site.
- Fabco Industries provided StormBasin inserts that met the high threshold for water quality treatment.
- Due to inconsistencies within the constructed inlets, Fabco had to design and fabricate a total of 18 different models to complete the project.
Project Issue #1: Acceptable Water Quality Treatment
Fabco Industries’ StormSacks, ScreenBoxes and StormBasins are recognized by the EPA and the State of Pennsylvania as stormwater inlet controls/water quality filters. Not all inserts are evaluated and recognized for the same pollutant removal efficiencies. Ferguson Waterworks representatitves Rob Woodman and Greg Kramer introduced the project engineer to Fabco to work out the details.
Fabco’s StormSack and ScreenBox recognized removal efficiencies of 60% TSS, 50% TP and 20% NO3 were not acceptable for this project. Another solution was needed!
Fabco’s standard filter cartridge (used in a variety of StormBasin designs) with recognized removal efficiencies of 80% TSS, 60% TP and 40% NO3 were acceptable for this project.
Project Issue #2: Fitting the inlets with Fabco StormBasins
The sixty plus inlets on this project consist of the following components:
A PennDOT Type M Precast Top
A PennDOT Type C Precast Top
Precast Inlet
Precast Risers
If the inlet tops are not aligned with the inlet or riser box, a ledge protrusion can be created that will impede the ability of the insert to fit the inlet. Some common protrusions in the inlet open space are:
Following are five example inlets with StormBasin filter inserts. The basic concepts to fit the StormBasin can be used for virtually any protrusions. StormBasin models for this project include variations of PLUS Dovetail units with plastic basins, or PLUS/BMP units with aluminum basins. Based on design, source and manufacturing efficiencies, the full aluminum basin unit is the most common and cost effective option.
Inlet Example #1: Shallow Inlet with Mild Pipe Protrusions
Pipes do protrude slightly into the inlet open space.
Fabco’s “A Type” Flat Flange allows the insert to sit higher on the inlet and avoid the pipes.
StormBasin overlay above shows how Fabco StormBasin insert fits the inlet.
Rendering of StormBasin 9730-1A Inlet Insert
Inlet Example #2: Ladder Rungs and Ribbed Grate
Ladder rungs are deep and not problematic, but this inlet does have a “ribbed” grate to be addressed.
Fabco’s drop flange allows the insert to sit lower in the inlet and avoid the ribs.
StormBasin “Type E” Flange provides a rubber divertor to capture overflow in the curb throat during severe events.
Rendering of StormBasin 9730-1E Inlet Insert
Inlet Example #3: Inlet with Severe Ledge Protrusion
Misaligned riser box creates a ledge that extends 6″ into the inlet open space.
StormBasin BMP with slotted aluminum frame is customized with extended frame deck.
Extended frame allows StormBasin BMP unit to bridge the ledge and fit the inlet.
StormBasin 2445-4E Inlet Insert
Inlet Example #4: Inlet Ladder Rungs and Ledges
Two pipes and the ladder rungs protrude into the inlet open space.
StormBasin BMP with slotted aluminum frame is customized with extended frame deck.
Two pipes and the ladder rungs protrude into the inlet open space.
StormBasin BMP Cartridge Based Filter 2445-4 Render
Inlet Example #5: Second Inlet with Ladder Rungs and Ledges
Misaligned riser box creates a ledge that extends 6.0″ into the inlet open space.
StormBasin BMP with slotted aluminum frame is customized with extended frame deck.
Extended frame desk allows the StormBasin BMP unit to bridge the ledge and fit the inlet.
StormBasin BMP Cartridge Based Inlet Filter 2445-2E Render Example
About Fabco Industries:
Fabco Industries is a leader in stormwater management. We design and manufacture high performance storm water filter systems that are highly effective for various treatment applications including retrofits, new construction and green infrastructure. Our range of cost-effective, durable products are designed to meet increasingly stringent pollution control regulations and best management practices for municipal and commercial stormwater markets.
We offer sustainable, simple-to-maintain filtration solutions to meet virtually any stormwater pollution control challenge. Innovative technology. Proven performance. Unbeatable quality and value. Discover all the reasons why Fabco gives you…Evolved Stormwater Solutions.