Water Quality

Please select a category from the menu on the left to see a list of questions.

Click on the question to see CWAG's answer.

If you have a question that is not answered here, please ask us by using the Contact button above. 


Is water from the Prescott and Prescott Valley municipal systems safe to drink?

Community systems such as Prescott, Prescott Valley, and private water companies are required to meet drinking water quality standards set by the U.S. Environmental Protection Agency (EPA), as authorized by the federal Safe Drinking Water Act. The standards are expressed as a Maximum Contaminant Level (MCL) for specific contaminants. The Arizona Department of Environmental Quality oversees compliance with the MCLs. With infrequent exceptions, our local communities meet these standards. They are required to provide bill payers with a yearly summary report of their compliance with the standards. Customers should read the annual report, including any notifications of noncompliance. Although regulatory agencies consider compliance with the standards as providing sufficient safety, some citizens use supplemental treatment devices in their homes.

Is arsenic a problem in our water?

Arsenic occurs naturally in some groundwaters in our region in concentrations that exceed the drinking water standard. Arsenic is associated with a number of adverse health effects and is known to cause several types of cancers. The U.S. EPA a few years ago, after years of investigation, revised the drinking water standard (MCL) to a more stringent value of 10 micrograms per liter (µg/L). Regulatory agencies consider that arsenic poses a risk of cancer at any level greater than zero; the lower the level of arsenic, the lower the risk of cancer.

Arsenic levels vary considerably in our area so it is difficult to predict where it will be a problem. Some areas in Paulden and southern Chino Valley have very high arsenic levels in groundwater. Some wells in the Dewey-Humboldt area exceed the arsenic MCL, and soil arsenic is very high near the Iron King Superfund site. There are certainly additional areas with arsenic problems. We recommend that every domestic well be tested for arsenic using testing methods approved by the State of Arizona. Arsenic removal systems for domestic use are available at reasonable cost.

Should I test the water in my well? How do I do that?

Although Federal and Arizona drinking water standards and testing regulations do not apply to wells for individual homes, well owners should have their well water tested periodically. The test results can be compared to the state standards. The Yavapai County Health Dept. refers inquiries about well testing to Bradshaw Environmental Inc. in P.V. They have a website at http://bradshawmtnenv.com

Why can’t I swim in Watson Lake? What’s all the green stuff in the water?

Watson Lake is owned by the City of Prescott (COP), which has posted signs that prohibit swimming and has expressed concern that the quality of the water is not sufficiently safe for swimming. The Arizona Department of Environmental Quality (ADEQ) has set water quality standards based on the intended use: full body contact (swimming).

Watson Lake is listed by ADEQ as an "impaired" water due to low dissolved oxygen levels and high levels of the nutrients nitrogen and phosphorus, which cause the algae and plant growth that is visible in the water as "green stuff." High levels of pathogenic (disease causing) microorganisms may also be present at times and pose a risk to swimmers. ADEQ is studying the lakes and working with the communities to try to meet ADEQ water quality standards. That will likely be a difficult and expensive task.


  • "Ranchers need clean water for their stock, farmers need it for their crops, every employer needs it to stay in business, and every living thing needs it for life... The law needs to be clear to protect water quality and the rights of landowners."
    Mark Udall
  • "Water is the driver of Nature."
    Leonardo da Vinci
  • "When the well is dry, we know the worth of water."
    Benjamin Franklin, Poor Richard’s Almanac, 1746
  • "...and since flow of information is to spirit what water is to life, we'd best think about how to keep the pipes free and unclogged."
    Raphie Frank
  • "In an age when man has forgotten his origins and is blind even to his most essential needs for survival, water along with other resources has become the victim of his indifference."
    Rachel Carson
  • "We forget that the water cycle and the life cycle are one."
    Jacques Yves Cousteau
  • "Water is life's matter and matrix, mother and medium. There is no life without water."
    Albert Szent-Gyorgyi, 1937 Nobel Prize for Medicine
  • "Water is everywhere and in all living things; we cannot be separated from water. No water, no life. Period..."
    Robert Fulghum
  • "It's the water. Everything is driven by the water."
    Mike Thompson
  • "Whiskey is for drinking; water is for fighting over."
    Mark Twain