GCASE Summary

Incorporating Climate Information and Stakeholder Engagement in Groundwater Resources Planning and Management

Planning to meet water demands in semi-arid regions is particularly challenging for groundwater dependent communities where aquifers are being replenished by intermittent streamflow events.  Projected and observed climatic changes for the Southwest increase uncertainties. The proposed project employs a novel modeling framework and extensive stakeholder interactions to achieve the following three objectives: (1) Address climate uncertainties with a sophisticated modeling framework; (2) Increase stakeholder capacity to adapt water planning and management to future climate uncertainties; and (3) Establish the transferability of the modeling framework and capacity building approach.  

The geographic focus is the Santa Cruz Active Management Area in south-central Arizona. On the border of Arizona with Sonora, Mexico, the city of Nogales, Arizona, and surrounding communities rely on water resources from a relatively shallow regional aquifer. Highly variable seasonal flow events on the Upper Santa Cruz River (USCR) are the main source of recharge to this aquifer and create a tightly linked relationship between localized aquifer conditions, streamflow variability, and regional climate patterns. Recognizing the interrelated hydrologic conditions, the Arizona Legislature formed the Santa Cruz Active Management Area (SCAMA) in 1994 and assigned the Arizona Department of Water Resources (ADWR) with the task of enforcing a two-part statutory management goal:  a) Maintain a safe-yield condition in the active management area; and b) Prevent local water tables from experiencing long term declines.

To assist it in developing an understanding of regional aquifer conditions, ADWR created a model depicting localized and regional hydrologic conditions and interactions between surface flows and aquifer conditions.  As required by state law, ADWR drafted Assured Water Supply (ASW) rules that have the potential to offer a leading example of sustainable management at multiple spatial scales. The adoption of the rules has been delayed. This delay is expected to be lengthy due to state budget cuts that have closed the SCAMA field office. The delay in rule adoption provides the project team with an opportunity to work with highly interested and knowledgeable stakeholders to incorporate greater climatic uncertainty in water planning and management. Through extensive work with stakeholders and agency personnel, this effort will demonstrate how groundwater management efforts, specifically the assured water supply program, can incorporate climate science/climate change information and surface water-groundwater connectivity.

This work is funded under a grant from the Sectoral Applications Research Program (SARP) of the National Oceanic and Atmospheric Administration (NOAA) Climate Program Office. The views expressed represent those of the authors and do not necessarily reflect the views or policies of NOAA.