Post-Project Assessment of the 2003 Cerrito Creek Restoration and Recommendations for Additional Stormwater Management

ABSTRACTA 700-foot-long daylighted reach of Cerrito Creek defines the southern border of the 29-acre El Cerrito Plaza shopping center and receives a majority of the Plaza’s stormwater runoff. In 2003, this reach, between Talbot and Kains Avenues, underwent a restoration project that widened, re-graded and re-vegetated the channel as well as added a gravel pedestrian path parallel to the stream. The project was completed while the shopping center and parking lot underwent a major renovation. In this study, we assessed current creek conditions and compared them to the original project design as well as a 2005 post-project assessment. We found that there may have been minor channel incision since 2005, but this evidence was unreliable due to the cross section locations having not been permanently monumented. An increase in the number of gravel bars, and an increase in the diversity of sediment size indicated that the stream was transporting sediment. Native vegetation planted during the restoration appeared to be flourishing, although we documented a few invasive species that have established as well. Although the creek restoration was successful at creating wildlife habitat and a new amenity for the public, it did not address the treatment of stormwater, raising concerns about the impacts of potentially harmful urban runoff on creek water quality. We considered options to retrofit stormwater management infrastructure and concluded that flow-through biofiltration structures such as sand filters, basins, or planters would be most feasible based on the local soil conditions and available land area