6101 ASSOCIATED BLVD BASE FILE 2017-06-05

Vortechs° As a storm subsides,treated runoff decants out of the Vortechs The Vortechs system is a high-performance hydrodynamic system at a controlled rate, restoring the water level to a dry- separator that effectively removes finer sediment(e.g. weather level equal to the invert of the inlet pipe.The low water 50-microns(um),oil,and floating and sinking debris.The swirl level facilitates easier inspection and cleaning, and significantly concentration operation and flow controls work together to reduces maintenance costs by reducing pump-out volume. minimize turbulence and provide stable storage of captured Design Basics pollutants. Precast models can treat peak design flows up to 30-cfs(850-L/s);cast-in-place models handle even greater flows. Each Vortechs system is custom designed based on site size,site A typical system is sized to provide a specific removal efficiency runoff coefficient, regional precipitation intensity distribution, of a predefined particle size distribution (PSD). and anticipated pollutant characteristics.There are two primary methods of sizing a Vortechs system.The first is to determine Operation Overview which model size provides the desired removal efficiency at a Stormwater enters the swirl chamber inducing a gentle swirling given flow for a defined particle size or PSD.The second and flow pattern and enhancing gravitational separation. Sinking more in depth method is the summation of Rational Rainfalt pollutants stay in the swirl chamber while floatables are stopped Method" which uses a summation process described below in at the baffle wall.Vortechs systems are usually sized to efficiently detail and is used when a specific removal efficiency of the net treat the frequently occurring runoff events and are primarily annual sediment load is required. controlled by the low flow control orifice.This orifice effectively Typically Vortechs systems are designed to achieve an 80%annual reduces inflow velocity and turbulence by inducing a slight solids load reduction based on lab generated performance curves backwater that is appropriate to the site. for either 50 jtm particles,or a particle gradation found in typical During larger storms,the water level rises above the low flow urban runoff(see performance section of this manual for more control orifice and begins to flow through the high flow control. information). Any layer of floating pollutants is elevated above the invert of The Rational Rainfall Method' the Floatables Baffle Wall,preventing release.Swirling action Differences in local climate,topography and scale make every increases in relation to the storm intensity,while sediment pile site hydraulically unique.It is important to take these factors into remains stable.When the storm drain is flowing at peak capacity, consideration when estimating the long-term performance of the water surface in the system approaches the top of the high any stormwater treatment system.The Rational Rainfall Method flow control.The Vortechs system will be sized large enough so combines site-specific information with laboratory generated that previously captured pollutants are retained in the system, performance data,and local historical precipitation records to even during these infrequent events. estimate removal efficiencies as accurately as possible. —, HIGH FLOW CONTROL SWIRL CHAMBER -- -OUTLET PIPE INLET PIPE OUTLET CHAMBER ___7! 1 ' LOW FLOW CONTROL FLOATABLES CHAMBER '- FLOATABLES BAFFLE WAL L 2