California Sea Grant College Program

We proposed directed field and modeling research to address the following hypotheses: (H1) Submarine groundwater discharge (SGD), its quality, and the percentage that is fresh versus saline, is modulated by season, tides, and wave conditions; (H2) the chemical (nutrient, carbon, trace metal) and biological (human health indicators) composition of SGD is affected by land use and geology; (H3) human health indicators and nutrients can be freely transported through the beach aquifer and are not removed via interactions with the sediments, and (H4) SGD impacts the water quality of the nearshore environment at a level comparable to surficial runoff.