PROTECTING DRINKING WATER RESOURCES: A CONSERVATION PRIORITY INDEX FOR VULNERABLE SOURCE WATER AREAS IN NEW HAMPSHIRE

Abstract

Growing development pressure and increasingly heavy rainfall events threaten New Hampshire's surface waters and the drinking water supplies they support. While Source Water Protection Areas have been designated around public water supplies, many lack formal conservation protection or planning. This project uses geospatial analysis to identify and prioritize unprotected areas for conservation based on vulnerability and landscape sensitivity. Using ArcGIS Pro, statewide datasets were integrated to assess multiple risk factors: impaired waterways, land cover-based runoff potential, FEMA flood hazard zones, and terrain-derived hydrological characteristics. These factors were standardized to construct a Conservation Priority Index identifying where water resources face the greatest cumulative threats. Results demonstrate that many Source Water Protection Areas remain unprotected and overlap with impaired waterways or areas with elevated runoff potential. High-priority zones are concentrated in central and southeastern regions, where land development pressure intersects with complex topography. The Conservation Priority Index provides a spatial support tool to guide conservation strategies that safeguard public water supplies. By identifying where protection efforts would yield the greatest benefit, this index helps target limited conservation resources more effectively. As development continues and climate change intensifies precipitation events, strategic protection of Source Water Protection Areas will become essential for ensuring safe drinking water and maintaining resilience across New Hampshire.