Built in the 1950s, the previous parking lots at the Alameda County Public Works Agency’s buildings, located at 951 and 951A Turner Court in Hayward, Alameda County, were due for an upgrade – specifically, implementation of low-impact development (LID) and stormwater runoff water quality treatment measures. In addition to treating local runoff at the parking lots, the project serves as a demonstration site for LID concepts with interpretive signage and workshops for Alameda County contractors and Clean Water Program stormwater managers. Alameda County had a specific design goal in mind, which included installing 14 different LID measures to determine which were cost-effective and sustainable. LID measures implemented at the site included bioretention, tree-wells, rain gardens, rainwater harvesting, silva cells, and porous pavement.
As the lead consultant, WRECO designed various LID/stormwater treatments and worked closely with Alameda County throughout the project. WRECO used “Bay-Friendly” rated landscaping that included drought-tolerant, native, and climate-adapted plants and trees in order to conserve water while creating a diverse and colorful landscape. At 951 Turner Court, impervious areas were reduced from 84% to 35%, and at 951A Turner Court, impervious areas were reduced from 50% to 40%.
The project was funded in part by the Proposition 84 Storm Water Grant Program.
Piloting innovative stormwater treatment best management practices (BMPs) with existing, aging infrastructure required extra time coordinating with proprietary vendors and revising their specifications for ease of implementation by the contractors. This project was delayed and went out to bid twice because of the numerous non-standard BMPs being tested and limited flexibility for contractors. This project has proven as a learning experience for both design and construction.
Electrical lines were also upgraded and/or created to provide connections for planned solar panels (to be installed as a separate project in the future) as well as to help power the new irrigation features, electrical vehicle charging stations, and the existing buildings’ electrical needs.