The City of Tacoma and Metro Parks Tacoma shared a vision of stormwater treatment through a park amenity. The Point Defiance Regional Stormwater Treatment Facility provides innovative stormwater treatment using a large-scale regional facility. The success of this facility can be applied to other basins and has the potential to change the way stormwater professionals look at water quality treatment in marine environments.
The facility captures and treats pollutants from a 720-acre watershed before they wash into an impaired area of Puget Sound which is overloaded with heavy metals from the Tacoma Asarco Smelter Plume. As an amenity, the facility was designed to take advantage of a challenging steep slope and provide interest at the entrance of the park through an impressive six-pool waterfall. The integration of the stormwater treatment elements with proposed park improvements allows visitors to see the stormwater treatment facilities and realize their impact on the stormwater system and consequently Puget Sound. The concrete pools provide a powerful reflective mirror for all to see how we impact the world around us. The innovative approach provides a tremendous amount of treatment in a very small footprint, with only 5,500 square feet of surface area.