Public Water Systems

In Ohio, around 4,400 public water systems serve approximately 11 million people daily.

Public water systems (PWSs) are regulated by the Ohio EPA Division of Drinking and Ground Waters (Ohio EPA DDAGW). Public water systems use either a ground water source, a surface water source or a ground water under the direct influence of surface water source. In Ohio, around 4,400 public water systems serve approximately 11 million people daily. Public water systems are required to monitor their water regularly for contaminants. Currently, more than 95% of community water systems meet all health-based standards. When a system doesn't meet a standard, consumers are notified.

For information about individual programs, please see the pages below. 

What is a public water system?

A public water system (PWS)is defined in Ohio Administrative Code 3745-81-01as a system that provides water for human consumption to at least 15 service connections or regularly serves an average of at least 25 individuals for at least 60 days each year. This includes water used for drinking, food preparation, bathing, showering, tooth brushing, dishwashing, and handwashing. A system could meet the definition of a PWS either by meeting the service connection threshold or by meeting the population threshold. PWSs range in size from large municipalities to small churches and restaurants relying on a single well.

In addition, systems associated with agricultural labor camps, defined in Ohio Revised Code 3733.41, are regulated as public water systems even though they may not meet the service connection or population thresholds.

These are the three categories of PWS:

  • Community water systems are PWSs that serve or could serve the same residents year-round. Examples include cities, mobile home parks, and nursing homes.
  • Nontransient, noncommunity water systems are PWSs that regularly serve the same persons over six months per year and are not a community water system. Examples include schools, hospitals, and factories.
  • Transient noncommunity water systemsare PWSs that do not regularly serve the same persons and are not a community or non-transient, non-community water system. Examples include campgrounds, restaurants, and gas stations.

For more detailed definitions of a public water system, service connection, regularly serve, and other terms used above, along with an explanation of how population counts are determined, additional examples, and other information, please reference Ohio Revised Code 6109.01 and Ohio Administrative Code 3745-81-01.

Private water systems are systems that do not meet the definition of a public water system. These systems are regulated by the Ohio Department of Health. Private water systems typically include such things as households and small businesses.

Understanding Your Drinking Water

In a typical community public water system, water is transported under pressure through a distribution network of buried pipes. Smaller pipes, called house service lines, are attached to the main water lines to bring water from the distribution network to your house.

In many community water systems, water pressure is provided by pumping water up into storage tanks that store water at higher elevations than the houses they serve. The force of gravity then "pushes" the water into your home when you turn on your tap.

Some water suppliers use treatment processes if it's necessary to remove contaminants from the drinking water. The most commonly used processes include filtration, flocculation, sedimentation and disinfection. If you want to know what types of treatment are used for your water supply, contact your local water supplier or public works department.

More information about where your drinking water comes from is also available.

The Multiple Barrier Approach to Protecting Public Health

U.S. EPA and Ohio EPA use a multiple barrier approach to defend against waterborne pathogens and chemical contaminants in drinking water. Protection against contaminants occurs at each step from source to tap, beginning in the watershed or aquifer recharge area, continuing at the treatment facility and extending through the distribution system.

Source Water Assessment and Protection

Selection of the best source of water available is an important step in protecting against contamination. For surface water sources, this means locating and constructing water intakes to ensure little or no contamination. For ground water sources, this means constructing wells in appropriate locations, at appropriate depths and with approved construction methods (e.g., casing and grouting).

Source Water Assessment and Protection helps public waters systems understand where the drinking water comes from, how contaminants can get into the water supply and how to protect the water from contamination at the source. Ohio EPA completes source water assessments for every public water system. Each assessment includes:

  • Delineating (or mapping) the source water assessment area;
  • Conducting an inventory of potential sources of contamination in the delineated area;
  • Determining the susceptibility of the water supply to those contamination sources; and
  • Releasing the results of the determinations to the public.

The results of the assessment can be used to organize, develop and implement a source water protection plan.

System Design and Operation

Plan approval ensures that the system is well-engineered and constructed to reliably protect finished water from contamination. The type of treatment required depends on the physical, microbiological and chemical characteristics and the types of contaminants present in the source water. Also, storage facilities and distribution systems must have full circulation and avoid stagnant water conditions that might facilitate contamination.

Sanitary surveys are routine inspections of public water systems to ensure proper construction and operation. The purpose of the sanitary survey is to evaluate and document the capabilities of a water system’s sources, treatment, storage, distribution network, operation and maintenance and overall management to continually provide safe drinking water and to identify any deficiencies that might adversely impact a public water system’s ability to meet applicable regulations and provide a safe reliable water supply.

Competent operating personnel are vitally important to the safety of drinking water. Ohio EPA's Operator Certification rules require that certain public water systems have a certified operator that is qualified to operate the system. To become a certified operator, a person must meet educational and experience requirements, pass an exam and maintain their certification through continuing education (contact hours).

Resources

Additional Resources for Public Water Suppliers

Contact Information

For questions related to specific public water systems, please contact the local Ohio EPA district office of the Division of Drinking and Ground Waters or contact the public water system directly.

Rules, Policies, Procedures and Guidance

Engineering and Plan Approval

Please see the engineering webpage for the most current versions of these documents.

Information to Assist Small Public Water Systems

General Resources