Tri-Basin Natural Resources District (TBNRD) requests proposals from qualified firms interested in providing engineering services to develop a groundwater supply evaluation tool. Groundwater level changes have been observed across TBNRD for more than 45 years. TBNRD needs a tool for understanding spatial and temporal changes in groundwater levels, to evaluate and identify trends and key factors. This tool will be used for analysis of groundwater supply trends for the purpose of helping the TBNRD Board of Directors make policy decisions regarding groundwater quantity management and groundwater supply augmentation.