A*    Understanding
      	1  |  the Safe  Drinking  Water Act
 % ^/
The Safe Drinking Water Act (SDWA) was
originally passed by Congress  in 1974 to protect
public health by regulating the nation's public drinking
water supply.

The law was amended in 1986 and 1996 and  requires
many actions to protect drinking water and its
sources—rivers, lakes, reservoirs, springs, and ground
water wells. (SDWA does not regulate private wells
which serve fewer than 25 individuals.)

SDWA authorizes the  United States  Environmental
Protection  Agency (US EPA) to set national health-
 All public water systems must have at least 15
 service connections or serve at least 25 people per
 day for 60 days of the year.
 Drinking water standards apply to water systems
 differently based on their type and size:
 Community Water System
                           re are approximately
                        rstem that serves the
                        ost residences including
homes, apartments, and condominiums in cities,
    ^ll towns, and mobile home parks are served by
    rnunitv Water Systems.
 Non-Community Water System
                                  lie water
                           but does not serve the
                            are two types of non-
 Non-Transient Non-Community Water System
 system that serves the same people more than six
 months per year, but not year-round, for example,
 a school with its own water supply is considered  a
 non-transient system.
 Transient non-community water system
 system that serves the public but not the same
 individuals for more than six months, for example,
 a rest area or campground may be considered a
 transient water system.
                                                   based standards for drinking water to protect against
                                                   both naturally-occurring and man-made contaminants
                                                   that may be found  in drinking water.  US EPA, states,
                                                   and water systems  then work together to make sure
                                                   that these standards are met.
   lions of Americans receive high quality drinking
water every day from their public water systems, (which
may  be publicly or privately  owned). Nonetheless,
drinking water safety cannot be taken for granted.

There are a number of threats  to drinking water:
improperly disposed  of chemicals;  animal wastes;
pesticides; human threats; wastes injected
underground; and naturally-occurring substances can
all contaminate drinking  water.

Likewise, drinking water that is not properly treated
or disinfected, or which travels through an improperly
maintained  distribution system, may also pose a health

Originally, SDWA focused primarily on treatment as
the means of  providing safe  drinking water at the tap.
The 1996 amendments greatly enhanced the  existing
law by recognizing source water protection, operator
training, funding for water system improvements, and
public information as important components  of safe
drinking water. This approach  ensures the quality of
drinking water by protecting  it from source to tap.

1996 SDWA Amendment Highlights:
Consumer Confidence Reports
                              r they
provide, including information on detected
contaminants, possible health effects, and the
water's source.
Cost-Benefit Analysis
                       JS EPA must conduct a
                    t analysis for every new
                    ne whether the  benefits of
                    ndard justify the costs.
Drinking Water State Revolving Fund
    o help systems assess an
                                     t their
Microbial Contaminants and Disinfectioi
             •  microbial  contaminants,
             ptosporidium, while strengthening
control over the byproducts of chemical
disinfection. The Stage 1 Disinfectants and
Disinfection Byproducts  Rule and the  Interim
Enhanced Surface Water Treatment Rule
Operator Certification
                           ter system
                       ified to ensure that
guidelines in February 1999  specifying
minimum  standards for the certification and
recertif ication of the operators of community
and non-transient, noncommunity water
systems.  These guidelines  apply to state
Operator Certification Programs. All states
are currently implementing EPA-approved
operator  certification programs.
                                     ght to
know what is  in their drinking water, where
it comes from, how it is treated, and how to
help protect it. US EPA distributes public
information materials (through  its Safe
Drinking Water Hotline, Safewater web site,
and Water Resource Center] and holds public
meetings, working with states, tribes,  water
systems, and  environmental and civic groups,
to encourage  public involvement.
        ater Systems
                        mall water system
                        eration and resource;
under SDWA, to make sure they have the
managerial, financial, and technical ability to
comply with drinking water  standards.
Source Water Assessment Programs
reservoirs, springs, and  ground water wells]
to identify significant potential sources
of contamination and to  determine how
susceptible the sources  are to these threats.
Roles and Responsibilities:

SDWA applies to every public water system in
the  United States. There are currently more than
1 70,000 public water systems providing water to
almost all Americans at some time in their lives. The
responsibility for making sure these public water
systems provide safe drinking water is divided among
US EPA, states, tribes, water systems, and the  public.
SDWA provides a framework in which these parties
work together to  protect this valuable resource.

US EPA sets national standards for drinking water
based on sound science to protect against health
risks, considering available technology  and costs.
These National Primary Drinking Water  Regulations
set enforceable maximum  contaminant levels for
particular contaminants in drinking water or required
ways to treat
water to remove
Each standard
also includes
requirements for
water systems
to test for
in the water
to make su re
standards are
ach ieved . In
addition to
setting  these
standards, US
EPA provides
and public
about drinking
water, collects
drinking water data, and oversees state drinking water

The most direct oversight of water systems is
conducted by state drinking water programs.  States
can apply to US EPA for "primacy," the  authority to
implement SDWA within their jurisdictions, if  they
can show that they will adopt standards at least as
stringent as US EPA's and  make sure water systems
meet these standards. All states and territories, except
Wyoming and the District of Columbia,  have  received
primacy.  While no Indian tribe has yet applied for
and received primacy, four tribes currently receive
"treatment as a state" status, and are eligible for

primacy. States, or US EPA acting as a primacy agent,
make sure water systems test for contaminants, review
plans for water system improvements, conduct on-site
inspections and sanitary surveys, provide training and
technical assistance, and take action against water
systems not meeting standards.

To ensure that drinking water is safe, SDWA sets up
multiple barriers against pollution.  These  barriers
include: source water protection, treatment, distribution
system integrity, and  public information. Public water
systems are responsible for ensuring that contaminants
in  tap water do not exceed the standards. Water systems
treat the water, and must test their water frequently
for specified contaminants and report the results to
states. If a water system is not meeting  these standards,
it is the water supplier's responsibility to notify its
customers. Many water suppliers  now are  also required
to  prepare annual  reports for their customers. The
public is responsible for helping local water suppliers
to  set priorities, make decisions on funding and system
improvements, and establish programs to  protect drinking
water sources. Water systems across the nation rely on
citizen advisory committees, rate boards, volunteers, and
civic leaders to actively protect this resource in every
community in America.
Protection & Prevention:

Essential components of safe drinking water include
protection and prevention. States and water suppliers
must conduct assessments of water sources to see
where they may be vulnerable to contamination. Water
systems may also voluntarily adopt programs to protect
their watershed or wellhead, and states can use legal
authorities from  other laws to prevent pollution. SDWA
mandates that states have programs
to certify water system operators and
make sure that new water systems
have the technical, financial, and
managerial capacity to provide  safe
drinking water. SDWA also sets  a
framework for the  Underground
Injection Control (UIC) program
to control the injection of wastes
into ground water. US EPA and
states implement the UIC program,
which sets standards for safe waste
injection practices and bans certain
types of injection altogether. All of
these  programs help prevent the
contamination of drinking water.
 US EPA sets primary drinking water
 standards through a three-step process:
 adversely affect public health and occur in drinking
 water with a frequency and at levels that pose a
 threat to public health. US EPA identifies these
 contaminants for further study, and determines
 contaminants to potentially regulate. Second, US
 EPA determines a maximum contaminant level goal
 for contaminants it decides to regulate. This goal is
 the level of a contaminant in drinking water below
 which there is  no known or expected risk to health.
 These goals allow for a margin of safety . Third,
 US EPA specifies a maximum contaminant level,
 the maximum permissible  level of a contaminant  in
 drinking water which is delivered  to any user of a
 public water system. These levels are enforceable
 standards, and are  set as close to  the  goals
 as feasible. SDWA defines feasible  as the level
 that may be achieved with the use of the best
 technology, treatment techniques, and other means
 which US EPA finds  (after examination for efficiency
 under field conditions] are available, taking  cost
 into consideration. When it is not economically or
 technically feasible  to set a maximum level, or when
 there is no  reliable  or economic method to  detect
 contaminants in the water, US EPA instead sets a
 required Treatment Technique which specifies  a way
 to treat the water to remove contaminants.
Setting National Drinking Water

US EPA sets national standards for tap water which help
ensure consistent quality in our nation's water supply.
US EPA prioritizes contaminants for potential regulation
based on risk and how often they  occur in water supplies.
(To aid in this effort, certain water systems monitor
                              for  the presence of
                              contaminants for which
                              no national standards
                              currently exist and
                              collect information
                              on their occurrence).
                              US  EPA sets a health
                              goal based on risk
                              (including risks to the
                              most sensitive people,
                              e.g., infants, children,
                              pregnant women,
                              the elderly, and the
                              immu no-compromised).
                              US  EPA then sets a
legal  limit for the contaminant in drinking water or a
required treatment technique—this limit or treatment
technique is set to  be as  close to the health goal as

feasible. US EPA also performs a cost-benefit analysis
and obtains input from interested parties when setting
standards.  US EPA is currently evaluating the  risks
from several specific health concerns, including:
microbial contaminants (e.g., Crypfospon'dium); the
byproducts of drinking water disinfection; radon;
arsenic;  and water systems that  don't currently
disinfect their water but get it from a potentially
vulnerable  ground water source.

Funding and Assistance:

US EPA provides grants to implement
state drinking  water programs, and to
help each state set up  a  special fund to
assist public water systems in financing
the  costs of improvements (called the
drinking  water state revolving fund).
Small water systems are given special
consideration, since  small systems
may  have a more difficult time paying
for system  improvements due to their
smaller customer base. Accordingly,
US EPA and states provide them with
extra assistance (including training
and funding) as well as allowing, on
a caseby- case basis, alternate water
treatments  that are less expensive,  but
still protective of public health.

Compliance and Enforcement:

National drinking water standards are legally
enforceable, which means that both US EPA and states
can take enforcement actions against water systems
not meeting safety standards. US EPA and states may
               issue administrative orders, take legal actions, or
               fine utilities. US  EPA and states also work to increase
               water systems, understanding of, and compliance with,

               Public Information:

               SDWA recognizes that since everyone drinks water,
               everyone has the  right to know what's in it and
               where it comes from. All water suppliers must  notify
                             consumers  quickly when  there is a
                             serious problem with  water quality.
                             Water systems serving the same people
                             year-round must provide annual
                             consumer confidence reports on the
                             source and quality of their tap  water.
                             States and  US EPA must prepare annual
                             summary reports of water system
                             compliance with drinking water safety
                             standards and make these reports
                             available to the public.  The public
                             must have a chance  to be involved in
                             developing source water assessment
                             programs, state plans to use drinking
                             water state revolving  loan funds, state
                             capacity  development plans, and state
                             operator certification programs.

               For More Information:

               To  learn more about the Safe Drinking  Water Act or
               drinking water in  general, call the Safe  Drinking Water
               Hotline at 1-800-426-4791, or visit US EPA's  Office
               of Ground Water  and Drinking Water web site: www.
Office of Water (4606)
EPA 816-F-04-030 June 2004