Strategy for Resolving MeHg and Low Dissolved Oxygen Events- Northern Suisun Marsh — State Water Resources Control Board
Siegel, S., P. Bachand, D. Gillenwater, S. Chappell, B. Wickland, O. Rocha, M. Stephenson, W. Hei, C. Enright, P. Moyle, P. Crain, B. Downing. B. Bergamaschi. 2011. Final Evaluation Memorandum, Strategies for Resolving Low Dissolved Oxygen and Methylmercury Events in Northern Suisun Marsh. Prepared for the State Water Resources Control Board, Sacramento, California. SWRCB Project Number 06 283 552 0. May.
Siegel, S., P. Bachand, D. Gillenwater, S. Chappell, B. Wickland, O. Rocha, M. Stephenson, W. Heim, C. Enright, P. Moyle, P. Crain, B. Downing. B. Bergamaschi. 2011. Best Management Practices Report , Strategies for Resolving Low Dissolved Oxygen and Methylmercury Events in Northern Suisun Marsh. Prepared for the State Water Resources Control Board, Sacramento, California. SWRCB Project Number 06 283552 0. July.
The 116,000 acre Suisun Marsh is the largest contiguous brackish water marsh remaining on North America’s west coast and represents a critical part of the San Francisco Bay-Delta estuary ecosystem. Almost half of the marsh is comprised of managed wetlands that experience seasonal flood-drain-flood cycles depending on environmental conditions and property manager objectives. In northwestern areas of the Marsh, fall flooding cycles cause severe drops in dissolved oxygen (DO) concentrations. These low DO plumes can impact aquatic ecosystems, killing at-risk fish species and impairing valuable fish nursery habitat. The low DO also can lead to elevated levels of methylated mercury (MeHg) and dissolved organic carbon (DOC), both linked to ecological and human health concerns.
The study identifies processes and practices that drive severely low DO events and MeHg and DOC production in managed wetlands, test new management practices to mitigate poor water quality conditions, and assess Best Management Practices for the broader managed wetlands community in Suisun Marsh. To achieve these goals, we partnered with a broad stakeholder group. The collaborative nature of this demonstration project allows for robust data collection, including continuous water quality monitoring, discrete water quality sampling, soil and vegetation analyses, and aquatic toxicology measurements. Our findings will aid regulatory agencies in developing policies that concurrently improve management strategies and environmental quality in the Suisun Marsh and the greater Bay Area.