Hydrology and channel form of an urban creek : Rheem Creek in the context of restoration efforts
Rheem Creek is a three mile long urban stream, located in California’s western Contra Costa County. Since 1960, Rheem Creek has been impacted by humans in a number of ways, including channelization for flood control purposes and residential development. Due to the deteriorated state of Rheem Creek, local community groups have partnered with stream restoration organizations to clean-up and rehabilitate the Creek. Little field data exists on the conditions of the Creek itself, or on the geomorphic, hydrologic, water quality and ecological conditions at specific sites. To overcome this barrier, and serve as a resource for local restoration efforts, this study aimed to: 1) Offer an additional qualitative overview of the human impacts on Rheem Creek and 2) Quantify the hydrologic and channel form conditions at the Contra Costa College immediately downstream from a proposed restoration project.
This study reveals that variable conditions exist along Rheem Creek, including the presence of a 100-foot undisturbed riparian corridor, straightened and stagnant waste pools, and stormwater pipes that drain directly into the Creek. Longitudinal and cross-sectional surveys at Contra Costa College show the existence of five distinct reaches within the College grounds, and highlight the need to consider coordinated restoration efforts between the Contra Costa College and restoration groups in order to avoid passing upstream problems to downstream sites; this includes exacerbating the flooding problem on the valley flats. Results from this study serve as a benchmark for planned upstream restoration projects and future monitoring efforts that will measure the impact of the projects over time.