Future Flow

By Angie Johnson-Schmit

Water Management and Conservation in Prescott Valley.

Water is what allows us to keep our bodies functioning, grow our food, keep our businesses and industries thriving, and maintain our outdoor recreation areas. While it seems incredible that a simple chemical compound made up of two atoms of hydrogen bonded with a single atom of oxygen is responsible for so much, our physical health and the health of our economy depend on water. To keep the water flowing to meet these needs in Prescott Valley, AZ, water resource management and water conservation are necessary.

Arizona relies on four main sources of water. These include surface water, water from the Colorado River, effluent, and groundwater.

Surface water encompasses water from lakes, rivers, and streams. The Colorado River provides over a third of the water used in Arizona, primarily to Maricopa and Pima counties. Effluent water is reclaimed water and is most commonly used for industries, recreational areas like parks and golf courses, and agriculture.

Groundwater is water found in aquifers, or underground reservoirs. From an economic standpoint, groundwater is one of Arizona’s most valuable resources. In 2020, the Economic Importance of Groundwater in Arizona, 2010-2018 study, conducted by Arizona State University, the W. P. Carey School of Business, and the L. William Seidman Research Institute, was released. It found that groundwater generates approximately $1.2 trillion dollars for the state economy.

Approximately 43% of Arizona's water comes from groundwater.

As part of managing this resource, areas that rely primarily on mined groundwater are designated as Active Management Areas (AMAs). A large part of Yavapai County, including Prescott Valley, Prescott, Chino Valley, parts of Dewey-Humboldt, the Yavapai-Prescott Indian Tribe reservation, and other areas fall under the Prescott AMA.

These AMAs fall under the Arizona Department of Water Resources (ADWR) and must also adhere to the Groundwater Management Act of 1980. This act essentially lays a path to water resource security by requiring AMAs to reach “safe yield” by 2025. Safe yield means achieving a rough balance between the amount of water taken from the aquifer and the amount returned to the aquifer.

Photocredit: Michael Wilson, Lynx Creek Falls

When the Prescott Valley area was first settled in the late 1800s, it was populated mainly by farmers and ranchers. Then known as Lonesome Valley, the agricultural community served as a major food supply for surrounding communities. As the number of settlers increased, so did the need for water. Manmade reservoirs were built with an eye to providing water for both agricultural irrigation and drinking water. It wasn’t long before surface water was no longer enough to meet the needs of the community.

In the 1930s, turbine pumps were used to pump groundwater from the vast aquifer underneath the land. Soon, like many municipalities around the state, more groundwater was being pumped to meet the community needs. The Groundwater Management Act of 1980 was a heavily contested state-level attempt to address water concerns in Arizona. Whether or not this act provides the best balance for the state’s water future continues to be debated to this day.

Arizona originally planned to use Colorado River water imported by the Central Arizona Project (CAP) Canal in place of groundwater. While the CAP Canal provides over a million acrefeet of water to the Phoenix and Tucson AMAs, the project was not extended to transport water to the Prescott AMA. Instead, the Prescott AMA sold their Colorado River water allotment to Scottsdale and was granted the right to import water from the Big Chino Aquifer.

Ensuring there is enough water to support the population of the Prescott AMA is a complex issue. The challenge for the Prescott AMA is to meet the safe yield goal of the Groundwater Management Act of 1980 with fewer water resource options. According to the Town of Prescott Valley, “the only legally available source of water for the Prescott AMA is the Big Chino Sub-basin as defined in Arizona Revised Statues section 45- 555.”

While there is a large underground reservoir of water about 500 feet beneath the surface of the town, it is not a resource that can be utilized at will. To reach the safe yield goal, Prescott Valley is pursuing the Big Chino Water Ranch project and to use treated reclaimed water, or effluent, to recharge the aquifer. The state of Arizona has regulated programs for this process.

Like many other communities in the region, the Town of Prescott Valley is actively working to meet these challenges through a combination of water management and water conservation. The good news is that the town has been doing a good job of both. With a per-capita use rate of less than 100 gallons per day, Prescott Valley has one of the lowest water use rates of the regulated municipalities in Arizona.

The town has implemented a variety of conservation efforts. The WaterSmart program is a multi-municipality program aimed to educate the public on ways they can conserve water, including rainwater harvesting. Prescott Valley has also instituted a tiered block rate water cost that has resulted in a downward daily water use trend since the program began in 2004.

With a per-capita use rate less than 100 gallons per day, Prescott Valley has one of the lowest water use rates of the regulated municipalities in Arizona.

Outdoor landscaping is another water conservation focus for Prescott Valley. Unlike Phoenix, Prescott Valley is taking the need to reduce outdoor landscape watering seriously. Michael J. Pearce, an attorney and expert in water rights, water management and water policy matters said, “Prescott valley has been kind of an outstanding example of adopting the new trend of xeriscape.”

Xeriscaping focuses on choosing plants and trees that are drought tolerant and either do not need irrigation or need only limited watering to thrive. The town has adopted xeriscape landscaping, both for city properties and in new home developments. A simple, beautiful and effective method to conserve water, xeriscaping stands in contrast with the water intensive landscaped grass lawns, trees and plants found in urban areas like Maricopa County.

In line with this xeriscaping approach and with a grant awarded by the U.S. Bureau of Reclamation, the town installed smart irrigation clocks that calculate water needs in public spaces according to weather data. This technology also sends alerts about the mechanical functioning of the system, letting Parks Department staff know if there is a sprinkler that needs to be mended or replaced.

Maintaining groundwater supplies while meeting the needs of growing municipalities is a tricky balance. The complexities of water rights and how to continue municipal growth without removing more groundwater requires continued scientific study and innovation. Long term solutions will likely include both legislative action on water, and employing developed technology, such as desalinating water from the ocean.

Arizonans are a resourceful lot, though, and are committed to ensuring water security for the state. As communities like Prescott Valley keep one eye on their water resources and the other on the future, their water resource management and conservation efforts will continue adapt and innovate to meet the challenge.