Practical Uses of GIS for Public Water Systems

Public water systems face ongoing challenges, including aging infrastructure, limited staffing, and increasing regulatory requirements. These challenges are often greater for small, rural, and tribal systems that may not have dedicated technical staff or centralized records. Geographic Information Systems (GIS) provide a practical and flexible way to organize information, understand system layout, and support daily operations, regulatory compliance, and planning. When used at an appropriate scale, GIS can help systems make better decisions without adding unnecessary complexity.  

Using GIS to Document Lead and Copper Inventories 

Midwest Assistance Program, Inc. (MAP) staff used GIS to support tribal public water systems in Minnesota by documenting lead and copper inventories in response to requirements under the Lead and Copper Rule. This work focused on mapping service line locations and recording known or suspected pipe materials so systems could submit accurate inventory information. MAP staff helped map over 1,200 service lines for a tribal community and was able to give them a spreadsheet detailing the material of every service line.  

Linking inventory data to maps allows systems to easily review their records, identify unknown materials, and update information as new details become available. GIS-based inventories also provide clear documentation during regulatory reviews and help systems plan future investigation or replacement efforts. 

Suggested Uses of GIS for Asset Management 

Beyond this specific example, GIS can be used more broadly by public water systems to support asset management. Utilities may choose to map wells, treatment facilities, water towers, hydrants, valves, pressure tanks, and other system components. Each mapped asset can be linked to basic information such as installation year, condition, and maintenance notes.  

Viewing infrastructure on a map helps operators understand how the system is connected, identify critical assets, and plan maintenance or replacement work. GIS can also support emergency response by showing valve locations and helping staff isolate affected areas during main breaks or water quality issues. 

Inventory and Recordkeeping Opportunities 

GIS can serve as a central location for storing equipment and facility information. Systems may use GIS to track pumps, control panels, treatment equipment, chemicals in storage, and other plant components. Well construction details such as depth, casing type, and pump settings can also be linked to mapped locations.  Keeping records in GIS reduces reliance on paper files and information stored across multiple computers. Centralized records can make inspections, audits, staff training, and day-to-day operations more efficient, especially for systems with limited staff or turnover. MAP staff are currently working with a Tribal community to document all information on all their lift stations. The on-site visits are using GIS technology to collect all the pump data. Additionally, a map and spreadsheet resource are being developed for the Tribal operator to utilize long term.  

Supporting Regulatory Compliance 

Regulatory compliance was another area where MAP staff used GIS to help public water systems. MAP staff used GIS to create and maintain sampling plans for requirements such as the Revised Total Coliform Rule, the Lead and Copper Rule, and the Disinfection Byproducts Rule. Sampling locations were mapped so operators knew where to collect samples and could more easily document compliance. 

Over time, MAP staff updated GIS sampling plans as systems changed, helping keep sampling locations accurate, reducing errors, and providing clear records during sanitary surveys and inspections. 

Planning, Funding, and Communication 

GIS is also a useful tool for planning and communication. Maps and visual information can help systems explain infrastructure needs to their governing boards, community members, and funding agencies. GIS outputs may support capital improvement planning, funding applications, and long-term decision-making. 

Many systems can begin using GIS with free or low-cost tools such as QGIS, Google Earth Pro, or simple spreadsheet-based inventories. Systems can start small and expand their use of GIS as staff capacity and needs grow. 

Using GIS for Targeted Data Collection in Schools 

In addition to regulatory-focused work, MAP staff also used GIS to support a school drinking water project through targeted data collection. Drinking water stations within school buildings were mapped to document how many access points existed and where they were located. 

This project was intentionally limited in scope and focused on collecting accurate location-based information to support planning and funding decisions. The GIS documentation helped support funding requests aimed at improving student access to safe drinking water, demonstrating how GIS can be applied to short-term projects with clear public health benefits. 

Conclusion 

MAP staff’s use of GIS for lead and copper inventory documentation and school drinking water data collection shows how GIS can be applied in practical, focused ways to meet specific needs. At the same time, GIS offers many additional opportunities for public water systems to strengthen asset management, regulatory compliance, planning, and communication. By starting with manageable projects and building over time, systems can use GIS to support a safer and more reliable drinking water service. 

This article is funded by EPA under RCAP’s NPA 1 Drinking Water 2024-2026 grant.