Agua Fria River Petroglyphs

Arizona Water: limited perennial stream reaches and vulnerability to baseflow loss due to increased reliance on ground water requires careful management to assure the sustainability of water resources, community character, and long-term economic health of Arizona.
Introduction to Water Quality Management

BLM document on Water Quality laws in Arizona

 

1. What is Water Quality?

 

Water Quality is a term used to describe the chemical, physical, and biological characteristics of water, usually in relation to its suitability for a particular purpose, such as drinking water or wildlife use.

 

 

2. What is Non-point Source Pollution?

Nonpoint source (NPS) pollution, unlike pollution from industrial and sewage treatment plants, comes from many diffuse sources. NPS pollution is caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters, and even our underground sources of drinking water.

 

These pollutants include:

    Excess fertilizers, herbicides, and insecticides from agricultural lands and residential areas;

    Oil, grease, and toxic chemicals from urban runoff and energy production;

    Sediment from improperly managed construction sites, crop and forest lands, and eroding streambanks;

    Salt from irrigation practices and acid drainage from abandoned mines;

    Bacteria and nutrients from livestock, pet wastes, and faulty septicsystems;

 

Atmospheric deposition and hydromodification are also sources of nonpoint source pollution. (http://www.epa.gov/owow/nps/qa.html)

 

 

3. What is a TMDL?

A TMDL or Total Maximum Daily Load is a calculation of the maximum amount of a pollutant that a waterbody can receive and still meet water quality standards, and an allocation of that amount to the pollutant's sources. Water quality standards are set by States, Territories, and Tribes. They identify the uses for each waterbody, for example, drinking water supply, contact recreation (swimming), and aquatic life support (fishing), and the scientific criteria to support that use.

 

A TMDL is the sum of the allowable loads of a single pollutant from all contributing point and nonpoint sources. The calculation must include a margin of safety to ensure that the waterbody can be used for the purposes the State has designated. The calculation must also account for seasonal variation in water quality. The Clean Water Act, section 303, establishes the water quality standards and TMDL programs. (http://www.epa.gov/owow/tmdl/intro.html)

 

 

4. What are Best Management Practices (BMPs)?

Best Management Practices (BMPs) to control nonpoint source pollution problems are a combination of structural and non-structural (management or cultural) practices that a scientist, engineer, the government, or a planning agency decides upon to be the most effective and economical way of controlling a specific water quality problem without disturbing the quality of the environment.

 

 

5. What is Water Quality Management?

The purpose of water quality management is to achieve sustainable use of our water resources by protecting and enhancing their quality while maintaining economic and social development. Water quality management involves the identification and assessment of point and non-point source pollutants and their sources, and then determining the best management practices to control those pollutants to meet water quality standards.