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Source: ENVIRONMENTAL MONITORING HANDBOOK
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WATER
WATER QUALITY GUIDELINES
Barry T. Hart
INTRODUCTION
Most countries now have water resources management policies aimed at achieving sus-
tainable use of their water resources by protecting and enhancing their quality while main-
taining economic and social development. Achieving this objective requires that the needs
and wants of the community for each water resource are defined and that these resources
are protected from degradation. These community needs generally are called the environ-
mental values (or beneficial uses) of the water body and can include water for drinking,
swimming, fishing, recreation, agricultural food production, and/or ecosystem protection.
Water quality guidelines (or criteria) are the scientific and technical information used
to provide an objective means for judging the quality needed to maintain a particular envi-
ronmental value. Knowledge-based management decisions made on the basis of this scien-
tific knowledge are far more preferable than those resulting from pressure by narrowly
focused lobby groups.
A number of water quality guideline compilations are now available (e.g., USEPA,
1986a; CCREM, 1991; ANZECC, 1992). With few exceptions, these are broadly similar in
their approach and in the threshold values they recommend. However, the recently released
Australian and New Zealand water quality guidelines mark a radical departure from the
conventionally derived water quality guidelines (ANZECC/ARMCANZ, 2000a). The key
elements of these new guidelines are that they are risk-b