Huntington Beach Dry Weather Diversion, Oxidation Treatment & Wetland Treatment System

Huntington Beach, California

Using a combination of engineered wetlands and the restored Talbert Lake, this project provides urban dry-weather runoff treatment for a 22 square mile municipal watershed. This system involves the diversion of nuisance flows from a regional flood control channel to the wetlands area, a series of interconnected wetland treatment cells and manmade lake polishing systems. By recreating a natural biological process, this project develops a managed ecosystem that provides water quality treatment.

Advanced Elements:

• In-channel flow interception facility capable of capturing dry-weather flows but not interfering with the flood control channel hydraulic capacity.
• Underground diversion pump station which is integrated into flood control channel maintenance roadway.
• Utilizes the existing municipal storm drain system to deliver flows to the park and minimizes force main construction.
• Specialized interconnected naturalized treatment cells consisting of alternating shallow wetlands and wetland ponds.
• Wetlands include specialized surface and subsurface wetland treatment elements utilizing specialized media for the growth of treatment bacterial biofilters.
• Naturalized treatment system design within the park designed so that existing active park areas are not lost, and aesthetics and passive recreation are enhanced.
• Restoration of an existing ephemeral lake within the park provides year round water storage and final polishing treatment with submerged media biofilters, submerged aeration, and wetland planters system.
• Restored lake serving as irrigation storage for park, eliminating potable water use for irrigation.