Pierce County Environmental Services 950 64th Street West • University Place, Washington
Reduce downstream damage from runoff
Safely move, control, contain rainwater
Capture rain for reuse (of all kinds, human and natural, from irrigation and toilet flushing to groundwater recharge)
Restore or create habitat
The basic stormwater management concept at PSECB is capture, convey, cleanse, convey and cleanse more, then infiltrate, accomplished in a linear sequence of multiple treatment techniques. Roof runoff from the main building falls from a scupper into a concrete basin (made with Steilacoom gravel aggregate, a nod to the site’s history); the basin is incised with a spiral, so runoff spirals through and on to a created wetland. Any overflow continues via pipe across the building entry plaza to bioretention gardens; excess runoff continues down a bioswale that also accepts runoff from adjacent parking lots and the main pedestrian path. Bioswale overflow is carried via pipe across a road to a backup in-system flow splitter that’s pretty unique: here 2 valves divert half of the runoff into a grass-lined swale and half into a gravel-lined swale, while a third valve, currently unused, will divert some runoff into a yet-to-be-developed type of system based on future advances in technology. All remaining runoff, including from the playing fields, infiltrates.
The PCESB site design successfully combines public recreation and site reclamation in a multi-faceted landscape that not only celebrates rain, but visually links the resource of rain to the larger natural landscape and educates visitors at every turn.