United States         August 1989
        Environmental Protection
        Agency        EPA 57079-89-000

        Office of Water (WH-550A)
oEPA Public Water

        Our Nation's
        Drinking Water
                Printed on Recycled Paper


Water is important to everyone. Water covers
over two-thirds of our planet, makes up
almost two-thirds of our bodies, and is present
in almost every type of food and drink. In
fact, we cannot live without water.

Fortunately, our planet has a lot of water —
more than 300 trillion gallons. The natural
"water cycle" continually replenishes this vast
supply, through precipitation, runoff and
percolation, evaporation, condensation,
precipitation again, and so on.  Because of its
abundance and availability, water has many
uses. Literally every home, store, business,
farm, factory, church and school relies on
water every day — for cooking, cleaning, and
bathing, for manufacturing and industrial
processes, for irrigation and livestock, for
sewage removal,  and most importantly, for
drinking water. Imagine the inconvenience if
your home or workplace was without running
water for even a day or two!!

Unfortunately, not all water is "potable" or
"drinkable." In fact, most water is not drink-
able without some kind of treatment.  Most
people in our country receive their water from
a public water system (only 15 percent of our
population obtains their water from house-
hold wells and springs). We rely on these
public water systems to gather, treat, and
deliver water to us each day.


Delivering clean water is no easy task. Both
the forces of nature and the activities of
modern, industrialized society present many
threats to the cleanliness and safety of our
water. Many different types of contaminants
can threaten our lakes, rivers, reservoirs, and
groundwater wells. As a result, public water
systems must work hard to make drinking
water free of disease-causing contaminants
and suitable for our use. Following are some
examples of the potential threats to our
drinking water

Threats from Nature
•  Bacteria, viruses, and other microorgan-
•  Naturally occurring radioactive materials
    such as radium and radon;
•  Naturally occurring metals, such as
    arsenic, cadmium, and chromium; and
•  Nitrates and nitrites from the breakdown
    of organic wastes.

Threats from Society
•  Chemicals both legally and illegally dis-
    charged from industrial and other proc-
•  Runoff from city streets, parking lots, and
•  Leakage of chemicals and wastes from
    underground storage tanks;
•  Runoff of agricultural pesticides and fertil-
•  Leachate from landfills and waste dumps;
•  Injection of waste fluids into underground
•  Improper use and disposal of household
    wastes, such as used oil, cleaning prod-
    ucts, and lawn and garden chemicals;
•  Faulty septic tanks and sewage systems.

Threats from Treatment and Distribution
•  Formation of disinfection by-products
    such as "trihalomethanes", corrosion by-
    products, and other contaminants result-
    ing from water treatment and distribution.


Congress has enacted several important
environmental laws which protect our nation's
waters. Among these laws is one designed

solely for the protection of drinking water —
the Safe Drinking Water Act of 1974.

This law required the development of:

•  National standards for drinking water
•  Monitoring and reporting requirements
   for public water systems; and
•  Regulations for underground injection of

The U.S. Environmental Protection Agency
(EPA) responded to these requirements by
•  National Primary Drinking Water Regu-
   lations. These are enforceable federal
   standards, which are established to protect
   the public against consumption of drink-
   ing water contaminants that present a risk
   to human health.
•  National Secondary Drinking Water
   Regulations. These are non-enforceable
   (at least at a federal level) guidelines,
   which are established to assist public
   water systems in managing their drinking
   water for aesthetic considerations, such as
   taste, color, and odor. These contaminants
   or physical conditions do not present a
   risk to human health at these "secondary
•  Provisions for state implementation and
   enforcement of the drinking water regu-
   lations. States may adopt their own
   regulations and assume responsibility for
   the drinking water program, provided the
   state regulations are no less strict than the
   federal requirements (more on this later).

In 1986, Congress enacted the Safe Drinking
Water Act Amendments. The amendments
revised and expanded the regulatory program
for public water supply systems. The new
requirements include:

•  Revision of the National Primary Drink-
   ing Water Regulations, which will
   initially result in the revision/develop-
   ment of regulations for 83 drinking water
   contaminants, to be followed by the
   development of regulations for 25 more
   contaminants every 3 years starting in
•  Revision/Development of the National
   Secondary Drinking Water Regulations;
•  A ban on the use of lead materials in
   public water systems and in plumbing
   that provides drinking water; and
•  Monitoring of a group of presently
   unregulated drinking water contami-
   nants, to gather information for future


In order to understand how drinking water is
managed, it is necessary to first understand
who is supplying the water, and further, who
is responsible for regulating the supplier.

Public Water Systems

By definition, a "public water system" has 15
or more service connections or regularly
serves an average of at least 25 people daily at
least 60 days each year. Public water systems
are split into two categories: community  and
non-community water systems.

A "community water system" has at least 15
service connections used by year-round
residents, or regularly serves at least 25 year-
round residents. These water systems gener-
ally serve cities and towns. They may also
serve  special residential communities, such as
mobile home parks and universities, which
have their own supply of drinking water.

A "non-community water system" can be
either a "transient non-community
system"(TNC) or a "non-transient non-
community system"(NTNC). TNCs typically

serve travelers and other transients at locations
such as highway rest stops, restaurants, and
public parks.  The system serves at least 25
people a day for at least 60 days a year, but
typically not the same 25 people each day.  On
the other hand, NTNCs do serve the same 25
persons for at least 6 months a year, but not
year round. Some common examples of
NTNCs are schools and factories (or other
workplaces) that have their own supply of
drinking water and serve 25 of the same
people each day.

States' Role
Each state has the opportunity to acquire
primary enforcement authority from EPA, and
by doing so, assumes responsibility for the
public water supply program. All states,
excluding Indiana and Wyoming and the
District of Columbia, have such authority. In
these three cases, EPA maintains responsibility
for the administration of the drinking water

If a state wants to acquire primary enforce-
ment authority, then it must adopt its own
health-based drinking water regulations that
are no less stringent than the federal require-
ments (states may always be more stringent).
These regulations represent the tapwater
quality goals that public water systems must
achieve.  As such, these regulations  are
designed to provide both short and long term
protection against adverse health effects that
may result from the consumption of drinking
water contaminants.

Once established, these state regulations
become the enforceable standards that must be
followed by all public water systems in that
state. In addition, the states must ensure that
the public systems continue to comply with all
applicable National Primary Drinking Water
Regulations. In order to provide assistance to
this effort, EPA, through its 10 regional
offices, provides regulatory and enforcement
oversight to each of the state programs.
The states also establish state design and
operation requirements for public water
systems.  These requirements may vary some-
what from state to state, but generally they
include the following:

•   acceptable operational procedures;
•   acceptable design and engineering
•   criteria for rate determination (i.e., how
    and what amount to charge);
•   criteria for identifying acceptable supply

These state design and operation require-
ments ensure that public water systems are
capable of achieving the federal health-based
tapwater quality goals.


•  First, identify your local water supplier.
    If you pay a water bill, the supplier's
    name, address and phone number should
    be on the bill. If you do not pay a water
    bill, contact your landlord, building
    manager, or the local health department—
    they should know.
•  Second, contact your local water supplier.
    Ask for the list of contaminants that the
    supplier must monitor and the standards
    they must meet. Further, ask for actual
    monitoring results that will assure you
    that your water supplier is providing safe
    drinking water.
•  Third, if you need further assistance or
    more information, contact your state
    drinking water program. Most state
    programs are located in the state capital
    (or another major city), and are usually
    part of the state department of health or
    environmental regulation.  Consult the
    blue "government pages" of your local
    phone book, or call the Safe Drinking
    Water Hotline.

•   Fourth, learn as much as possible about
    your local water supply — Who owns or
    operates the system? How can you
    become active in ensuring that your public
    water system supplies safe drinking
    water? How can you support your water
    supplier's efforts to improve existing
    facilities? Answers to these questions can
    be obtained from your local water sup-
    plier, your state drinking water program,
    or your county or city government.
•   Finally, support rate increases, where
    necessary, to upgrade your local water
    supplier's treatment facilities in order to
    meet drinking water standards.


For a good general overview of the public
water supply program and some insights into
the citizen's role, write or call to obtain these
two booklets:

Safety on Tap: A Citizen's Drinking Water
Handbook. Available from League of Women
Voters of the United States, 1730 M Street,
NW, Washington, DC  20036. (202)429-1965.
Publication #840.
Drinking Water: A Community Action Guide.
Available from CONCERN, Inc.,  1794 Colum-
bia Road, NW, Washington, DC  20009.
For more information on drinking water laws
and regulations, including a list of the state
drinking water programs, write:

        U.S. Environmental Protection Agency
        Office of Drinking Water
        401 M Street, SW
        Washington, DC 20460

Or call:  The Safe Drinking Water Hotline
        (800) 426-4791  or (202) 382-5533
 jUS GPO 1989—625-360