A MULTI-SCALE ANALYSIS OF BIOCLIMATIC AND ECOHYDROLOGIC FACTORS FOR GROUNDWATER DEPENDENT ECOSYSTEMS

Groundwater resources in the West are heavily relied upon to supply water for drinking, agriculture, industrial use, recreation, and to support groundwater dependent ecosystems (GDE) and their functions. GDEs are locations in the terrestrial landscape where groundwater is the principal source of water to the surface or near-surface, creating ephemeral, intermittent, or perennial surface water features such as springs or wetland areas that support aquatic, riparian, and terrestrial ecosystems. The study of GDEs can help to understand tipping points and ecosystem transformations for these sensitive areas and scientific research can help inform actions to build drought resilience. The USGS is developing an integrated science plan to describe the current state of GDEs in the West and to apply this information to better understand and predict the impacts that climate change, extended drought, and groundwater withdrawals may have on these ecosystems. We are looking to engage stakeholders to refine goals and establish priorities.

A seven-component multidisciplinary strategy has been developed to account for and understand the long-term impacts of drought and climate change on GDEs with the following goals:

1. Develop an automated delineation process to identify where GDEs could exist.
2. Compile existing multidisciplinary data and reports on GDEs. Work with stakeholders to determine the available data and prioritize future work.
3. Create new applications to build stakeholder capacity for updating information on GDEs.
4. Collect new data at prioritized GDEs.
5. Iteratively use multidisciplinary data to assess how changes in groundwater systems may affect GDEs across the landscape.
6. Determine how GDEs support ecosystem services through an iterative ecologic and biologic characterization on GDEs.
7. Quantify how changes in recharge lead to changes in groundwater discharge and water quality at GDEs and how these changes impact ecosystems, recreation, and consumptive use. Use these relationships to predict future changes at different spatial and temporal scales related to climate and drought scenarios.