Public Water Systems on the Navajo Nation

A PWS is a regulated water system that provides drinking water to a minimum number of people, usually 25, and any number of people over that amount. The PWSSP does not regulate water systems that provide water to fewer people, such as wells that are not hooked up to a PWS but instead serve individual families. The PWS regulations setting the standards for drinking water quality and the requirements for PWS owners and operators are available here.

The PWSSP conducts 40-50 on-site sanitary survey inspections per year of PWSs on the Navajo Nation, depending on the conditions of the PWS. These inspections are conducted to evaluate the adequacy of the source of drinking water, facilities, equipment, and operation and maintenance for producing and distributing safe drinking water. Systems using groundwater are inspected every 2-5 years depending on the condition of the PWS. Systems using surface water or Groundwater Under the Direct Influence (GWUDI) of Surface Water are inspected on an annual basis. Follow-up inspections are conducted 6 months to 1 year after the initial inspection, depending on the condition of the PWS and its compliance status.

Abandoned wells are frequently encountered during PWS inspections. The PWSSP works with the Navajo Department of Water Resources to ensure the proper abandonment of these wells. In the interim, PWSSP recommends that these wells be welded with a cap. Otherwise, they pose a threat to the overall quality of an aquifer, as pollutants can enter uncovered wells.

Categories of Public Water Systems

  • Community Water System (CWS)

    A public water system that serves at least 15 service connections used by year-round residents or regularly serves at least 25 year-round residents.

  • Non-Transient, Non-Community Water Systems (NTNCWS)

    A public water system that is not a community water system and that regularly serves at least 25 of the same persons for more than 6 months per year, including but not limited to schools, factories, and public buildings.

  • Transient, Non-Community Water System (TNCWS)

    A public water system that is neither a "community water system" nor a "non-transient non-community water system," including but not limited to seasonal facilities such as children's camps or recreational camping areas; and year-round facilities that serve more than 25 persons who are not residents thereof, such as gasoline service stations, marinas, rest areas and restaurants, and that are not served by a community water system. These systems are required to sample bacteriological quality on a quarterly basis and for nitrate/nitrite annually.

  • Consecutive Public Water System

    A public water system that purchases water from a primary purveyor. This type of water system typically purchases water, pumps the water into its own storage tanks, and distributes the water through its own pipes; schools and stores are examples of these systems. These systems are required to monitor for bacteriological quality on a monthly basis, as well as for lead, copper, and asbestos (if asbestos-cement pipes are used for distribution).