A short drive from downtown Seattle, a forested area near Mount Rainer was
developed for a new Centex home subdivision, The Arbors at Rock Creek.
The residential site needed a solution to protect the sensitive habitat and
groundwater within the Rock Creek Natural Area. Stormceptor inlet units were
selected to accept road runoff and pretreat a number of rain gardens and
gravel infiltration beds throughout the community.
Capture and retention of fine particles, sediment bound pollutants and
hydrocarbons for the pretreatment of stormwater runoff was an ideal fit
for incorporating Stormceptor. Removal of the urban pollutant load from
the surrounding roadways prior to water entering the rain gardens offered
a primary single point of maintenance. This provided the functionality and
aesthetic appeal of the Low Impact Development (LID) application.
For this LID/treatment train approach, Stormceptor was designed to capture and retain total suspended solids (TSS) and
hydrocarbons prior to discharge into the rain gardens.
Selection of Stormceptor eliminated the need for additional drainage infrastructure and provided the necessary pretreatment
for each of the rain gardens and infiltration beds, extending the life of the treatment systems, positively impacting the life-cycle
cost. Stormceptor offers lower overall maintenance cost, being easily inspected and maintained from grade at a single point. If
gone untreated, hydrocarbons, fine sediment and small debris could easily clog the downstream surface filtration systems, not
allowing them to function as designed.
The Stormceptor STC 450i’s key design flexibility features and low inlet to outlet drop made this unit ideal for pretreating
gardens and infiltration cells. At this site, surface runoff can enter units from both surface
inlet grates or from piped flow from other inlet structures. Stormceptor reduces infrastructure
cost by serving as a bend and junction structure, in addition to providing treatment.