Ohio State University Extension Fact Sheet

Ohio State University Extension Fact Sheet

Food, Agricultural, and Biological Engineering

590 Woody Hayes Dr., Columbus, Ohio 43210


Drinking Water Regulations

AEX-423-98

Martha Wells
Karen Mancl

Providing high quality drinking water to homes and businesses is a priority in Ohio and the nation. To accomplish this, the United States Congress first passed the Safe Drinking Water Act in 1974. The act charged the US Environmental Protection Agency (US EPA) to develop national drinking water standards and establish requirements for treatment, monitoring, and reporting by public water systems. The federal laws are interpreted by the US EPA and Ohio EPA in regulations that are constantly being revised.

Classifications of Public Water Systems

A public water system is defined as a system for the provision to the public of piped water for human consumption. Public systems serve at least 15 connections or regularly serve an average of at least 25 individuals daily at least 60 days of the year. Public water systems fall into three categories:

  1. Where people live - Community water systems (municipal systems, rural water districts and mobile home parks)
  2. Where people work - Nontransient, noncommunity water systems (schools, factories, and office buildings)
  3. Where people visit - Transient, noncommunity water systems (parks, motels, restaurants, and churches)

Public water systems are also classified into four categories by size. The classification of the water system determines the frequency of monitoring. The smaller the system, the more lenient the monitoring requirements.

Very Small Populationless than 250
Small Population250-3299
Medium Population3300-50,000
Large Populationmore than 50,000

Public Water System Responsibilities

The owners and operators of public drinking water systems are responsible to both the public and the state of Ohio. Local governments or private organizations that operate public water systems have several responsibilities that include:

  1. Obtain a drinking water license and plan approval from Ohio EPA.
  2. Hire a qualified (certified, if serving over 250 people) operator.
  3. Test drinking water and report the results to Ohio EPA and customers.
  4. Notify Ohio EPA and customers if a violation occurs.
  5. Correct any compliance problems.

Water systems hire certified systems operators to test and treat water. However, the system owner is ultimately responsible for compliance with regulations.

Drinking Water Standards

The Safe Drinking Water Act sets requirements for treatment, monitoring, and reporting by public water systems. The Act also directs the US EPA to identify contaminants and establish maximum acceptable levels in drinking water. The US EPA is charged with establishing national primary enforceable drinking water regulations for the protection of the public health and establishing secondary nonenforceable regulations that are related to taste, odor, and appearance of drinking water. Figure 1 on the next page illustrates how the number of standards have grown over a twenty-two-year period.

The specific allowable contaminant levels continue to change. For an up-to-date list, contact the district office of Ohio EPA or the US EPA Safe Drinking Water Hotline at 1-800-426-4791.

Figure 1

Adapted from "Drinking Water and Wastewater Regulation" by Martha Wells,
Tennessee Technological University. This project was supported, in part,
by the Ohio Small Community Environmental Infrastructure Group and the
National Environmental Training Center for Small Communities.


NOTE: Disclaimer - This publication may contain pesticide recommendations that are subject to change at any time. These recommendations are provided only as a guide. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. Due to constantly changing labels and product registrations, some of the recommendations given in this writing may no longer be legal by the time you read them. If any information in these recommendations disagrees with the label, the recommendation must be disregarded. No endorsement is intended for products mentioned, nor is criticism meant for products not mentioned. The author and Ohio State University Extension assume no liability resulting from the use of these recommendations.


All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status.

Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.

TDD No. 800-589-8292 (Ohio only) or 614-292-6181



| Ohioline | Search | Fact Sheets | Bulletins |