A State Playbook for Creating and Sharing Drinking Water Service Area Boundaries

There are nearly 50,000 community water systems in the United States that serve 90 percent of the population. Given the importance of water in the health, safety, economic mobility and overall well-being of the public, the EPA has released a comprehensive, nationwide map displaying water utilities and whom they serve.

States have a unique opportunity: help develop, update and provide feedback to the map of water system service areas for your state to improve the design and implementation of water infrastructure, rate design, drought planning, and numerous other programs. 

This State Playbook is designed to be a resource to state actors, but it can also inform action at the local or federal scale as well.

For general information on drinking water utility service area boundaries, learn more here.

Data Use

Better information about water service area boundaries can have cascading, long term benefits for water management. Interviews with several stakeholders revealed a number of applications that would be improved with accurate and accessible service boundary data, such as: projecting populations to estimate future water supply and demand; evaluating alternative water supply options; assessing climate change variability, including wildfire impacts on water supply; and determining grant eligibility and prioritization of State Revolving Fund allocation - among many others.

Learn more about specific use cases by using the drop down to the right.

  • Interviews with four states revealed a number of applications that could be improved with accurate and accessible service boundary data include: future water supply and demand projections to regionalization studies and emergency response. Read more from state agency representatives here.

  • Water service area boundaries could help agencies incorporate drinking water metrics into the Climate and Economic Justice Screening Tool and track who is benefiting from water infrastructure improvements. Read more about how service area boundaries could help implement the Justice40 program here.

  • Community members want to know where their water comes from. At the same time, many communities do not trust water authorities, in part due to significant information and communications gaps. By pairing water service area boundaries with other environmental indicators, states can help build trust in water systems and better address issues exacerbated by climate change. Read from advocate’s perspective how this data can be used in community engagement and advocacy here.

  • The lack of data on water systems that serve tribes has rippling effects wherein the inaccurate data at the local level is added to state-managed databases and then comprises analyses of states, policymakers, and researchers about access to safe drinking water. Read from EPIC’s Tribal Mitigation Manager about the importance of Tribal representation here.