Stormwater Flow Control Device

Regulated sources of wet weather pollution include stormwater, combined sewer overflows (CSOs), and sanitary sewer overflows. These programs require cost-effective flow control and treatment technologies as well as other watershed management measures to satisfy water quality criteria or total maximum daily load (TMDL) allocations. Cost-effective flow controls are needed in all of these market areas to maximize wet weather flows that can be treated without inhibitions of drainage system hydraulics or without any blockage of the flow path. Conventional flow control includes fixed weirs or more expensive mechanical devices that either inhibit the drainage system hydraulics or add to the capital and maintenance cost. Conventional approaches, in which devices or structures are placed in the flow path, add to the risk of upstream flooding or inadequate wet weather treatment. WWETCO, LLC, has developed a nonmechanical, passive-flow control device that will maximize flow attenuation and diversion of wet weather volumes to treatment. The flow control will not inhibit the existing drainage system hydraulic capacity, providing a full-bore flow path for transport of solids and trash without causing blockages or incomplete treatment. The WWETCO flow control device is simple, compact, and rugged enough to withstand high velocities carrying trash and abrasive materials and is not affected by corrosive environments. The WWETCO flow control can be installed at a cost similar to the most inexpensive fixed weir controls. The goals of this Phase I research project include development of the prototype flow control device and the evaluation of construction and fabrication materials. Alternatives will be tested in the WWETCO laboratory for examining hydraulic performance under the various flow control applications, including diversion, migratory tolerant attenuation, and inline storage optimization. Costs and performance will be evaluated to delineate cost effectiveness and other optimization benefits. Results will be used to define the work plan for Phase II full-scale testing at the Columbus, GA CSO Technology Demonstration Facility and at the City of Columbus 319(h) Best Management Practices Demonstration Project. The preliminary commercialization plan will be developed from Phase I research results and combined with local, state, and federal agency surveys of wet weather control needs. The Phase II commercialization plan will further define full-scale hydraulic and operation performance, fabrication and production, specific marketing strategies, information dissemination, teaming arrangements, and funding. Markets include municipal governments and the development community and are estimated at more than $40 million per year for the next 30 years. Funding will be leveraged with loans, private investments, and demonstration grants to accomplish Phase I and II efforts, including commercialization of the technology.