Mercury Imports and Exports of Four Tidal Wetlands in the Sacramento Valley, California

The California Department of Water Resources (DWR) measured import and export loads of methylmercury (MeHg) and total mercury (THg) at four tidal wetlands in the Sacramento Valley of California to comply with the Central Valley Regional Water Quality Control Board’s Delta Methylmercury Total Maximum Daily Load (TMDL). In addition to mercury, DWR collected organic carbon, total suspended sediment, chlorophyll-a, temperature, dissolved oxygen, specific conductance, turbidity, total chlorophyll, velocity, level, and flow data. To do this, three sets of data were collected: 1) velocity, level, and flow data were collected continuously using an Acoustic Doppler Current Profiler, 2) continuous temperature, specific conductance, salinity, dissolved oxygen, turbidity, and total chlorophyll were collected using a water quality sonde, and 3) THg, MeHg, organic carbon, total suspended sediment, and chlorophyll-a were collected via grab samples either by sampling pole or flow-weighted composites with an autosampler.