This project work will model the risk of pesticide pollution in 225 sub-catchments of the Sacramento-San Joaquin Bay-Delta. The model will account for water management practices, land use, pesticide use rates, and cumulative pesticide stress. Additionally, this work will produce a web-based tool to simulate current and future risks based on the ranking of primary sources of pesticide contribution. This work will provide a framework to predict risk from chemical stressors. Specific objectives are: (1) enhanced pro-active chemical risk assessment, (2) creation of a tool which enables science-based chemical use decisions, (3) improved risk screening for vulnerable areas, and (4) identification of adverse effects of current and future chemical use strategies.
The Sacramento-San Joaquin Delta is a highly altered and impaired ecosystem that is critical to the freshwater infrastructure of the State of California. Salt intrusion from San Francisco Bay into the Delta, however, threatens freshwater delivery to the southern portions of the state and so management and restoration actions within the Bay-Delta must continuously balance both ecosystem and operational needs. While previous numerical modeling studies have sought to examine changes in the estuarine physics of the system, these tools are costly to develop and run. Thus there is a need to develop alternate methods for monitoring the movement of water through the Bay-Delta, as proposed here. The proposed research project approaches tracking the mixing between the Bay and Delta waters through the novel use of daily satellite color imagery. These findings will be linked to in situ measurements throughout the system and used to inform relevant agencies of flow characteristics within the waterways. This work is motivated by a need for high frequency monitoring of finescale features within the dynamic Bay-Delta ecosystem and to take advantage of new advanced remote sensing technology to inform on long-term trends within the Delta.
The primary objectives of this research are to: 1. Enhance monitoring programs to inform management in the presence of climate change and additional stressors, 2. Inform on ecosystem resilience to interannual hydrologic variations and climate change impacts, and 3. Evaluate how climate change and flow regime changes will impact water quality in the Delta.