Caltrans Headquarters - Stormwater Quality Monitoring Program - San Francisco – Oakland Bay Bridge Bioretention Pilot Project

BMP influent monitoring point for use in pollutant load reduction analysis
Prime Contractor: 
Location: 
Period of Performance: 
December, 2008 to October, 2014
Project Description: 

In 2002, the California Regional Water Quality Control Board (RWQCB) San Francisco Bay Region issued a set of Waste Discharge Requirements (WDRs) to address post-construction stormwater runoff impacts associated with the proposed San Francisco-Oakland Bay Bridge East Span Seismic Safety Project (East Span Project). Caltrans associated Storm Water Management Plan (SWMP) was submitted to fulfill the requirements described in Provision D.10g of the WDR adopted by the RWQCB San Francisco Bay Region for the East Span Project. Provision D.10g of the WDR requires Caltrans to submit a final SWMP with final construction details and all other appropriate information associated with design elements from the original SWMP work plan.

To address the provisions of the SWMP, ADH has supported Caltrans since 2008, as a subcontractor on this five year study by providing programmatic and technical support to Caltrans District 4 decision makers to ensure successful implementation of the pilot project. ADH played a critical role, in consultation with Caltrans managers, to develop solutions to site-specific monitoring, sampling, and analyses challenges that were endemic to the implementation of the study. ADH successfully installed and operated over a dozen automated monitoring and sampling stations necessary to test the effectiveness of six bioretention basins to attenuate influent stormwater of a wide variety of physical, chemical and biological pollutants.

ADH Responsibilities: 
  • Installation, maintenance and operation of remote stormwater monitoring stations; equipment includes flow meters, primary devices, auto samplers, satellite telemetry, rain gauges and solar power
  • Remote data communication and instrument control; maintain a remote command center capable of reprogramming automated sampling equipment, real-time data acquisition and review, and focused dispatch of field crews during storms
  • Flow-weighted composite sample collection and manual grab sampling of specific constituents at peak storm flow
  • Identification and tracking of treatment bypass from planned and unplanned sources
  • Tidal monitoring and timed exclusion of bay water from biofiltration basins during monitoring events
  • Groundwater discharge flow monitoring from submarine passageway dewatering
  • Fish monitoring in storm drain system and installation of fish exclusion screens
  • Programming and operation of stormwater pump stations • Confined space entry operations
  • Vegetation maintenance
  • Erosion and sediment control BMP installation
  • Design flume extensions and installation
  • Coordination with Caltrans managers and maintenance staff regarding exclusion of tidal inflows, dewatering discharge to a stormwater pump station, presence of fish in the stormwater system, flow monitoring challenges, sources of treatment bypass
  • Database management and data analysis
  • Recommendations for improvements to monitoring technology
  • Preparation of post-storm technical memoranda components
  • Preparation of annual monitoring report components
  • Editorial review of memoranda and reports