Stream Maintenance Program Water Quality and Sediment Sampling Program

Horizon Water and Environment (Horizon) developed water and sediment quality monitoring programs for the Sonoma County Water Agency (SCWA) in support of their Stream Maintenance Program (SMP). Horizon worked closely with the North Coast and San Francisco Bay Regional Water Quality Control Boards (Regional Boards) to develop water and sediment quality monitoring and reporting programs to comply with Clean Water Act and Porter-Cologne requirements. For the water quality monitoring program, Horizon coordinated with the Regional Boards to refine and focus the list of sampled constituents, coordinated sampling, laboratory analysis, and guided SCWA and the Regional Boards in interpreting results.

For sediment quality monitoring, Horizon developed a Regional Board approved sampling methodology, identified sampling frequencies/locations, developed best management practices for sample handling, and importantly identified the relevant analytes for testing. Horizon staff coordinated laboratory analysis and prepared annual summary reports of the results. Horizon staff trained SCWA’s sampling crew on proper equipment decontamination and sampling procedures. A key role for Horizon was interpreting sediment quality results to determine allowable reuse and disposal options. Horizon then successfully obtained disposal approvals from the Regional Boards on behalf of SCWA.