United States
            Environmental Protection
            Agency
EPA/820/F-11/001 | February 2011 | water.epa.gov
WATER QUALITY STANDARDS:
 Prrte&wig H-uwuMi  H-ealtk  twui
 Aquatic Life,
We use water in a variety of ways. Humans drink it, swim
in it, wash with it and travel across it. We use water to cool
our machines and provide power to our cities. Aquatic
organisms, such as fish, snails, frogs and insects, live in
water for part or all of their lives. To protect human  health
and aquatic life, states, territories and authorized tribes
establish water quality standards regulating how clean
their water bodies should be. The Environmental Protection
Agency (EPA) reviews these water quality standards and
approves them if they meet the requirements of the Clean
Water Act and EPA's water quality standards regulations.
States, territories and authorized tribes are required to hold
public hearings to review water quality standards every
three years to ensure that the standards in their regulations
align with current science and uses of specific water bodies
by people and aquatic life. This review is an opportunity for
you to help protect the water bodies in your area. State,
territorial and tribal environmental departments need your
help to learn how water bodies in your area are used or
could be used.

WHAT ARE WATER QUALITY STANDARDS?
Set by each state, water quality standards regulate how clean a water body should be. The standards consist
of the water body's designated uses, water quality criteria to protect those uses and determine if they are
being attained, and antidegradation policies to help protect high quality water bodies.
  DESIGNATED USES. States designate water bodies
   for specific uses based on their goals and expectations
   for their waters. Typical designated uses include:
   -   Protection and propagation  of fish, shellfish and
      wildlife.
   -   Recreation.
   -   Public water supply.
   -  Agricultural, industrial, navigational and other
       purposes.
   A water body's designated use can be changed if the state, territory or authorized tribe can demonstrate
   that the water body's current use is not attainable and if  EPA approves of the change.

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    WATER QUALITY CRITERIA Water quality criteria
    are set to protect each designated use and are based
    only on data and scientific judgments about pollutant
    concentrations and their effects. Whether numeric
    or narrative in form, water quality criteria protect
    designated uses by describing the chemical, physical
    and biological conditions necessary for safe use of
    waters by humans and aquatic life. Definitions and
    examples of some criteria appear in the table below.
TYPE
Numeric
Criteria
Narrative
"Free From"
Criteria
Narrative
Biological
Criteria
DEFINITION
Lists the maximum pollutant
concentration levels allowed in a
water body.
Describes the desired conditions
for a water body as being "free
from" certain negative conditions.
Describes the kinds of organisms
expected in a healthy water body.
EXAMPLE
The maximum concentration of lead that aquatic life can
tolerate in a water body on a short-term (acute) basis is
65 micrograms of lead per liter of freshwater.
Free from excessive algae blooms.
Capable of supporting and maintaining a balanced,
integrated, adaptive community of diverse warm water
aquatic organisms.
   ANTIDEGRADATION POLICIES, states, territories
    and authorized tribes are required to complete the
    following:
    -   Protect existing uses and the water quality
        necessary to support such uses for all of their water
        bodies.
    -   Establish a public decision-making process for
        water bodies with water quality that is better than
        necessary to support the designated uses and for
        which  an activity is proposed that would lower
        water quality.
    -   Maintain and protect water quality of Outstanding National Resource Waters from degradation.
        Outstanding National Resource Waters are water bodies that a state chooses to protect most
        strictly.
    -   Identify methods for implementing their antidegradation policies.

HELP PROTECT YOUR WATER BODIES
   Check out your state's water quality standards
    regulations at http://water.epa.gov/scitech/swguidance/
    waterquality/standards/wqslibrary/index.cfm and
    contact your state's environmental department to voice
    your ideas  or concerns  about current or proposed
    standards.
   Contact your state's EPA regional water quality
    standards coordinator at http://water.epa.gov/scitech/swguidance/waterquality/standards/regions.cfm
    if you have questions or concerns.
   Attend public hearings or information sessions to learn about water-related issues in your state.
   Check the designated uses for the water bodies near you. Are you or people you know using water
    bodies in other ways? If so, tell your state's environmental department.
   Visit http://water.epa.gov/action for more ways you can  help protect and clean up your state's waters.

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