Baxter Creek Gateway Park: assessment of an urban stream restoration project

This study describes a post-project evaluation of the Baxter Creek Gateway Restoration Project located in a small, urbanized section of creek in the City of El Cerrito, Contra Costa County, California. The project was conducted to restore sinuosity, provide aquatic and riparian habitat, and enhance public access to a 700-foot section of channelized stream. Our assessment of this project’s performance (completed less than a year after the project was constructed) evaluated the restoration effort’s progress and provides a baseline for future assessments of the project as it matures. Assessment approaches and techniques included physical surveys of the creek’s longitudinal (long) profile and several cross sections, facies mapping of the creek’s bed structure, estimation of a sediment budget for the site’s drainage basin, observations of site users, interviews with community stakeholders, visual evaluation of vegetation success rates, and photo documentation of current site conditions.Although the restoration project is new and some intended features will take years to develop, we evaluated the project based on the proposed goals that we could measure and interpret with only two to three days of field work. We found that the creek’s planform was similar to the plans but detected some bank erosion as well as bed material transport from the upstream to downstream end of the project. The current sediment yield for the urban catchment is much less than during historical conditions. Based on bed structure measurements, sediments will need to be managed at the site as common flows were predicted to move gravels and cobbles in the restored reach. The quality of potential vegetative and aquatic habitat within the project site had increased as a result of the restoration, but the site’s surrounding culverted creek and urbanized landscape limit the feasibility of fish and amphibian colonization. Exotic riparian vegetation grew prolifically despite the fact that crews removed all vegetation during construction, planted only natives, and a citizen group frequently removed invasives. The multi-use trail and interpretive signs contributed to a successful recreational community space, but the trail will need improvements in connectivity beyond the project site before it can serve as a viable segment of the intercity Ohlone Greenway trail system. The current monitoring plan for the restoration is well written and includes important abiotic and biotic factors, but we also recommend installing a permanent stream gauge at the site, monitoring flood overflow conveyance in adjacent streets, conducting physical surveys of the long profile and established cross sections, and regular facies mapping