Technical Description:
- Debris Separating Baffle Box® Separators
- UrbanPond® Concrete Detention System
- (3) Modular Wetlands® Linear Bioretention Systems
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The development of a 16 acre commercial site directly adjacent to the Santa Ana River in Colton, California, resulted in the need for a robust stormwater treatment system.
Challenges included tricky soil conditions and the need to address pollutants of concern, such as oil, grease, total suspended solids (TSS), trash, debris, metals, and pathogens, along with meeting the regulations of the Santa Ana Regional Water Quality Board NPDES Permit and County of San Bernardino Water Quality Management Plan.
Thienes Engineering elected to partner with Contech to engineer a treatment train of three Contech devices: the Debris Separating Baffle Box (DSBB Separator), UrbanPond® concrete detention system, and the Modular Wetlands® Linear.
The UrbanPond, a traffic-rated underground stormwater storage system, was designed and produced with considerations such as height of cover, live and dead loads, proximity to adjacent structures, and required detention volume. This land-saving precast storage system allows for development above grade while providing stormwater storage below grade.
Upstream of the 156 UrbanPond modules is a 5’x’10’ DSBB that reduces flow velocity and separates floatables like trash, debris, oil, and sediment. Positioning the DSBB upstream of the UrbanPond pretreats the stormwater and supports the connected systems’ efficiency and long-term maintenance costs.
Downstream of the UrbanPond System are three 10’x20’ Modular Wetland Linear units. The Modular Wetlands will treat downstream flows from the UrbanPond for nutrients, heavy metals, hydrocarbons, and more. The units were engineered and sized for the required treatment flow rates, working together as a treatment train to address the pollutants of concern and meet local regulations.
This stormwater project in Colton represents the ability to engineer a creative treatment train system that satisfies local regulations while meeting unique challenges and site constraints.
Technical Description:
- Debris Separating Baffle Box® Separators
- UrbanPond® Concrete Detention System
- (3) Modular Wetlands® Linear Bioretention Systems
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