AquaShield™ Inc. manufactures stormwater treatment systems used worldwide to protect sensitive receiving waters from the harmful effects of stormwater. The Aqua-Swirl™ hydrodynamic separator removes gross sediment while the Aqua-Filter™ is a treatment train for the most sensitive stormwater applications. The Aqua-Guardian™ catch basin insert is an effective means of sediment removal for smaller projects. Every AquaShield™ system is custom engineered to meet the stormwater quality standards expected today.
AquaShield`s line of patented stormwater treatment products provide for three levels of stormwater treatment:
AQUA-SWIRL
The patented Aqua-Swirl™ Concentrator provides a highly effective means for the removal of sediment, floating debris and free-oil. Swirl technology, or vortex separation, is a proven form of treatment utilized in the stormwater industry to accelerate gravitational separation. Independent university laboratory performance evaluations have shown the Aqua-Swirl™ achieves a TSS (Total Suspended Solids) removal of 91% calculated on a net annual basis.
Each Aqua-Swirl™ is constructed of High-Density Polyethylene (HDPE), and is therefore modular, lightweight and durable, eliminating the need for heavy lifting equipment during installation. Inspection and maintenance are made easy, with oversized risers that allow for both examination and cleanout without entering the chamber.
System Operation
The Aqua-Swirl™ Concentrator Conveyance Flow Diversion System provides full treatment for the most contaminated first flush, while the cleaner peak storm flow is diverted and channeled through the main conveyance pipe. Many regulatory agencies are establishing water quality treatment flow rates for their areas based on the initial movement of pollutants into the storm drainage system.
The operation begins when stormwater enters the Aqua-Swirl™ through a tangential inlet pipe which produces a circular (or vortex) flow pattern that causes contaminates to settle. Because stormwater flow is intermittent by nature, the Aqua-Swirl Concentrator retains water between storm events providing both dynamic and quiescent settling of inorganic solids. The dynamic settling occurs during each storm event, while the quiescent settling takes place between successive storms. A combination of gravitational and hydrodynamic drag forces encourages the solids to drop out of the flow and migrate to the center of the chamber where velocities are the lowest, as shown from extensive CFD modeling.
A large percentage of settleable solids in stormwater are reported to be small and have low settling velocities. Therefore, the volume of water retained in the Aqua-Swirl™ Concentrator provides the quiescent settling that increases performance. Furthermore, due to finer sediment adhering onto larger particles (less than 200 microns), these larger particles settle rather than stay suspended in the water.
The treated flow exits the Aqua-Swirl™ Concentrator behind the arched outer baffle. The top of the baffle is sealed across the treatment channel, thereby eliminating any possibility of floatable pollutants to escape the system. A vent pipe is extended up the riser to expose the backside of the baffle to atmospheric conditions, preventing a siphon from forming at the bottom of the baffle.
AQUA-FILTER
The Aqua-Filter™ Stormwater Filtration System is designed for sites that require advanced treatment of runoff stormwater that may discharge into sensitive receiving waters.
The Aqua-Filter™ is not only unique because of its modular design, and HDPE construction, but also because of the ease of installation. The system can be designed for new construction projects or be retrofit for existing storm drainage structures.
System Operation
Each Aqua-Filter™ system is custom engineered and utilizes a unique approach for pollutant removal. This patented configuration begins with the removal of gross pollutants by the Swirl Concentrator, followed by the removal of fine sediments and water-borne pollutants by the Filtration Chamber.
The Aqua-Filter™ System is engineered such that the filtration capacity complies with established water quality treatment requirements. This means that the system filters the initial movement of fine sediment pollutants that can be particularly harmful.
The Aqua-Filter™ Stormwater Filtration System operates under gravitational and hydrodynamic forces with no moving parts or valves, which simplifies the treatment process. The Aqua-Filter™ System also normally operates in an off-line configuration as recommended by the Center for Watershed Protection and most municipalities; fully treating the more frequent 6-month to 1-year design storms (or roughly 90% - 95% of the annual rainfall on a given site).
AQUA-GUARDIAN
AquaShield Inc. has improved the patented Aqua-Guardian Catch Basin Insert by increasing the treatment flow rates while maintaining TSS and debris removal efficiency. Filtration of fine sediment and associated pollutants transported during the first flush of the storm continues to be the initial level of treatment.
Each Aqua-Guardian Insert includes a sediment collection/storage area within the HDPE structure.
System Operation
The Aqua-Guardian Catch Basin Insert is suspended inside the catch basin by a stainless steel support collar, which acts as a funnel to direct runoff water into the sediment collection and storage area. The support collar forms a baffle around the inside of the insert which acts to trap floatable debris, even during overflow conditions.
Stormwater enters the Aqua-Guardian from the surface and accumulates in the sediment chamber to begin the treatment process of capturing pollutants. As the storm continues, water flows through the locked filter screen standpipe and is dispersed over the filter media where fine sediment, petroleum hydrocarbons, nutrients (phosphates) and heavy metals (zinc) are removed before exiting the insert through the base plate.
As the runoff increases, water rises in the sediment chamber to the level of the filter screen outlets built into the perimeter of HDPE structure. Removal, or treatment, of sediment and debris continues at increased flow rates as shown in the Aqua-Guardian Catch Basin Insert Sizing Chart. The internal high-flow bypass openings at the top of the structure reduce the possibility of water backing onto the surface. The baffle formed by the stainless steel support collar prevents captured floatable debris from exiting through the overflow holes.
