Water Quality Sampling in Flowing Streams

Client: San Francisco Public Utilities Commission

In 2001, the Division of Safety of Dams of the California Department of Water Resources directed the San Francisco Public Utilities Commission (SFPUC) to reduce the water storage level in Calaveras Reservoir due to seismic safety concerns. To address these concerns, the SFPUC is constructing a replacement dam with improved seismic safety design.

The Calaveras Dam Replacement Project includes a new dam located immediately downstream of the existing dam, on Calaveras Creek. The excavation, placing, and grading of roughly 8 million cubic yards of rock and soil to create the new dam could release naturally occurring asbestos and various metals into the creek, which flows into Alameda Creek approximately 1,000 feet downstream of the new dam site.

The SFPUC developed a Water Quality Monitoring Program to address potential water quality issues associated with the dam replacement project. As part of that program, WRE engineers collected water samples from Alameda and Calaveras creeks for over a year and compiled data for over 35 constituents. Field measurements were collected and data compiled for seven water quality parameters.