Nonmechanical Device for Flow Control

WWETCO, LLC control device consists of a flexible bladder that The WWETCO flow control does not require addi - 753 Grimes Bridge Road opens at the bottom in a structure containing a tional head or a vertical drop in the drainage system Roswell, GA 30075 static fluid that seals the bladder against a conduit to operate. It creates a differential head in the that transports dry and/or wet weather flow. The drainage flow path between the maximum upstream Telephone: 404-307-5731 technology can be used in a or water con - water level (set by the static level in the structure) http://www.wwetco.com veyance channel, piping network, storage basin or and the downstream attenuated flow depth. Flow structure, and as a part of a treatment system. The and treatment controls, therefore, can be placed at WWETCO flow technology can be incorporated any location in the collection network or drainage Environmental Problem into the outlet of stormwater ponds to carry a fixed system where there is existing infrastructure, avail - water level during dry weather or to completely able land/waterway for storage, or where residual To satisfy criteria or total maximum drain yet maximize their effectiveness for each pollutant removals are advantageous. daily load (TMDL) allocations, regulated sources of runoff event. wet weather pollution (stormwater, combined sewer Commercialization Information overflows (CSOs), and sanitary sewer overflows) re - The flow control device uses differential hydraulic quire cost-effective flow control and treatment tech - pressure across the membrane to passively maintain Commercial applications include the optimization nologies. Flow controls maximize wet weather flows an upstream water level during changing flow con - of various flow controls, such as diversion, storage, that can be treated without inhibiting drainage sys - ditions. The flexible membrane takes on a shape to migratory tolerant stream attenuation, inline storage, tem hydraulics or blocking the flow path. Conven - create the head loss required to maintain the up - flow to treatment, creating head for treatment, tional flow control includes fixed weirs or more stream water level and pass the excess flow to the pond/stream level management, , fish lad - expensive mechanical devices that can inhibit the downstream level. The design allows the passage of ders, or other situations requiring the maintenance drainage system hydraulics or create higher capital aquatic biology or other base flows during dry of an upstream level. The preliminary commercial - and maintenance costs. Conventional approaches, in weather. During runoff conditions after the up - ization plan was developed from Phase I research which devices are placed in the flow path, risk up - stream storage has been fully utilized, the flexible stream flooding or less than optimal wet weather membrane lifts upward as needed to pass any ex - treatment. cess volume or debris. Because the bladder opens from the bottom of the conduit, it is non-clogging SBIR Technology Solution and provides full-bore peak flow. The technology can be designed to seal the conduit completely or With support from EPA’s Small Business Innovation partially, allowing passage for dry weather flow such Research (SBIR) Program, WWETCO, LLC has de - as in a combined sewer inline storage appli - veloped a nonmechanical, passive-flow control de - cation or stream/groundwater base flows. The vice that will maximize flow attenuation and WWETCO flow control provides diversion to treat - diversion of wet weather volumes to treatment. The ment, bypass around treatment, and/or attenuated WWETCO flow control can be installed at a cost base flow through the flow control. It optimizes the comparable to the most inexpensive fixed weir con - use of all available upstream storage before bypass - trols. The device is simple, compact, and able to ing any excess flow volumes not treated or stored. It WWETCO Compressed Media Filter and Flow Controls with handle high velocities carrying trash and abrasive also has the ability to bypass peak flow with no sys - ultraviolet disinfection for Weracoba Creek stormwater materials with virtually no maintenance. It is not af - tem capacity loss, eliminating any risk of upstream treatment in Columbus, Georgia fected by corrosive environments. The passive flow flooding.

SBIR Success Stories results and combined with local, state, and federal Company History manufacturing, operations, and performance testing. agency surveys of wet weather control needs. The Since 1996, WWETCO has provided watershed Phase II commercialization plan defined full-scale WWETCO specializes in the monitoring, measure - measurements and wet weather control technology hydraulic and operation performance, fabrication ment, evaluation, control, and treatment of wet- demonstrations for solutions to combined sewer and production, specific marketing strategies, infor - weather-related pollution. The managing principals of overflows (CSOs), stormwater, tertiary filtration, mation dissemination, teaming arrangements, and this environmental products and services firm have nutrient control, optimization of biological treatment, funding. Primary focus markets include the devel - an average of 33 years of engineering experience, in - lagoon controls and filtration and industrial opment community and municipal governments cluding planning, design, construction management, pollution issues. that are under regulatory requirements with an esti - mated average value of $40 million per year for the next 30 years (dependent upon geographic loca - SBIR Impact tion, state and federal regulatory activity, and new development).

The flow control technology was tested in a project n Cost-effective flow control and treatment technologies are required for that demonstrated an innovative retrofit of an exist - wet weather pollution, and conventional approaches are inadequate. ing stormwater pond serving a 300-acre commer - cial impervious area in the Roaring Branch n WWETCO has developed a non-mechanical, passive-flow control de - watershed, a tributary to the Middle Chatta - vice that can be installed at costs comparable to the most inexpensive hoochee in Columbus and Muscogee County, fixed weir controls, and requires virtually no maintenance. Georgia, and in a demonstration of disinfection and stormwater pollutant load reduction facility in Wer - n The device operates on a flow control-created hydraulic gradient that acoba Creek Watershed in Columbus, Georgia. Ad - allows placement of flow and treatment controls at any location along ditionally, the City of Columbus implemented a stormwater treatment system to control flow and fil - the collection network or drainage system where residual pollutant ter the runoff from its 7-acre vehicle maintenance removals are advantageous. facility. The WWETCO flow control device was in - stalled to provide passive wet weather treatment. n WWETCO’s flow control device provides The first two projects above were tested under EPA passive wet weather treatment for the City grant Quality Assurance Project Plan (QAPP) proto - of Columbus, Georgia’s stormwater treat - cols, with results showing that macro-invertebrate ment system. species increased 100-fold and 60-fold, respec - tively, downstream of these facilities. This improved water quality raised the impaired stream segments from a Class C to a Class A rating.

SBIR Success Stories