Russian River Erosion ControlGeyserville, California
California Department of Transportation
Caltrans retained Geocon under an emergency on-call contract to perform surface water quality monitoring during diversion of the Russian River to prevent erosion of the Geyserville Bridge abutment. The monitoring was performed in accordance with Central Valley Regional Water Quality Control Board permit requirements to minimize river water turbidity during placement of rock fills, redirective rock vanes and tree plantings. River water samples were collected simultaneously at designated upstream and downstream locations every 30 minutes. Construction activities were suspended where turbidity levels exceeded project-specific thresholds or when sediment plumes were visually identified.