Californian aquifers located near coastal regions face stress due to saltwater intrusion, which has contaminated many coastal aquifers, rendered municipal drinking water supplies unpotable, and has reduced vital freshwater discharge to coastal ecosystems.
A delicate balance must be struck between human groundwater demand and the strain on coastal environmental health. Without effective evaluation and management of coastal groundwater, the sustainability of coastal aquifers is in jeopardy, which will have negative ramifications for human use and the broader environment alike. Field scale studies using direct methods to resolve spatial saltwater intrusion are plagued by a lack of data, since many expensive and deep wells must be drilled to collect data in even a small—often biased—fraction of the area of interest.
We are learning more about the process of saltwater intrusion by integrating geophysical methods with geostatistics. In contrast to point measurements from wells, indirect geophysical methods provide near-continuous measurements over a sampled domain. These indirect measurements contain uncertainty, since the response signal is a function of multiple variables. To quantify and constrain uncertainty, we are integrating our geophysical data with geostatistical methods to simulate equiprobable earth scenarios, each of which explain our data.