Integrated Remote Sensing, Groundwater Monitoring & Modeling to Manage Groundwater-Dependent Ecosystems (GDEs)

California’s Sustainable Groundwater Management Act requires establishing measurable objectives, trigger thresholds and management actions to protect GDEs. Effective resource management must consider groundwater hydrology, surface-groundwater interaction, plant physiology, and habitat quality. We will discuss projects where remote sensing data were used to assess GDE stress and establish management action thresholds related to groundwater extraction, and present an approach that correlates GDE stress and habitat suitability indicators with hydrologic indicators to establish GDE management frameworks.

Satellite data were used to map spatial and temporal changes in Leaf Area Index (LAI) and wetland free water surface area, which are useful indicators of wetland health and productivity. For a site in eastern California, LAI over a 5-year period was compared to baseline conditions, and effects of groundwater extraction quantified. A change threshold was developed to trigger on-the-ground GDE surveys of habitat quality and degradation. The findings of these surveys and the remote sensing data were used to prepare a Habitat Suitability Index model and develop groundwater pumping prescriptions.

We propose a process which correlates remote sensing metrics of GDE stress with groundwater levels, stream baseflow, seepage discharge, ponding depth or other hydrologic indicators to establish a system of thresholds and escalating management actions.