Managing water in the desert

Drought cycles are normal for our arid region

Studies of tree rings provide long-term historical insights into the duration and severity of regional droughts and show that long dry periods with sporadic “spike years” are normal.

For example, the current drought cycle started in the mid-1990s, and is reportedly the most severe in over twelve hundred years. A wet winter in 2017 increased SRP’s year-over-year storage by nearly 20% to over three-quarters full. After the dry year that followed, reservoir storage fell to below half by the following October: 46% full. By April of 2020, the reservoir system was again 98% full.

The purpose of surface water management is to capture streamflow in wet years for delivery and use in subsequent dry years; you can find current water levels at watershedconnection.com.

Monitoring water quality

As a raw water provider, SRP delivers nonpotable water to municipal water providers and treatment plants who treat the water before it is delivered to homes, schools and businesses.  We also deliver nonpotable water to agricultural, residential and commercial irrigation customers. As part of our efforts to maintain a resilient water supply, we monitor the water quality of the rivers in our watersheds, as well as the water quality in our canals and from our groundwater wells in our service area.

What we do:

• Obtain permits and approvals as required by the Clean Water Act and the Arizona Aquifer Protection Program.
• Collect water quality samples from points along the rivers and canals and from our groundwater wells. Samples are tested at our lab, which is certified by the state of Arizona.
• Use computer modeling to track water quality conditions in SRP's water delivery system.

For questions about your tap water, contact your municipality or potable water provider.

Per- and polyfluoroalkyl substances (PFAS):

PFAS are a group of chemicals widely used in many consumer and industrial products. Because PFAS break down very slowly, they persist in the environment for a long time. Scientific studies have shown that exposure to some PFAS may be linked to harmful health effects in humans and animals.

The U.S. Environmental Protection Agency (EPA) has established regulations for PFAS in drinking water. SRP does not provide drinking water but nevertheless is taking proactive steps to understand EPA guidance and regulations related to PFAS. Drinking water providers must test for PFAS in their systems by 2027 and meet the drinking water standards for PFAS starting in 2029. As a raw water provider, SRP delivers non-potable water to irrigation customers, municipal water providers and treatment plants. Municipal water providers and treatment plants treat the water to meet drinking water quality standards before delivering it to end users. SRP irrigation water is not treated prior to delivery, and it is not suitable for human consumption.

PFAS have been detected in the groundwater in some areas of the Phoenix metropolitan area, including areas where SRP has irrigation supply wells. Neither EPA nor the Arizona Department of Environmental Quality (ADEQ) has established regulations for PFAS in irrigation water. The Arizona Department of Health Services has indicated that water with PFAS concentrations above the drinking water standards may still be used for land irrigation.

SRP will continue to comply with all water quality standards applicable to its water delivery system and monitor developments from the EPA and ADEQ regarding PFAS.

For more information:

• U.S. Environmental Protection Agency: Per- and Polyfluoroalkyl Substances (PFAS) | US EPA
• Arizona Department of Environmental Quality: PFAS Resources | ADEQ
• Arizona Department of Environmental Quality: PFAS | What's Important to Know | ADEQ
• Arizona Department of Health Services: PFAS_Infographic.pdf
• U.S. Department of Agriculture: Per-and Polyfluoroalkyl Substances (PFAS) | Farmers.gov

Maintaining healthy forests

Wondering what healthy forests have to do with our water supply? Quite a bit, actually.

The water we use every day comes from forests in northern and eastern Arizona. Every part of those forests, from the tree canopy to the soil, plays a role in storing and filtering our drinking water.

That’s why we’re taking steps to keep our forests healthy by partnering with the U.S. Forest Service and others to strategically thin areas that are overgrown and at risk of wildfire. Join us by supporting the SRP Healthy Forest Initiative™.

Supplementing surface water with groundwater

SRP’s conjunctive management of our surface water and groundwater supplies provides for a reliable supply of water despite recurring dry years.

SRP's 270 wells are operated to deliver groundwater in concert with surface water supplies and have the capacity to provide nearly half of SRP’s deliveries in a given year—bolstering our system resilience.

In anticipating and reacting to the dry conditions of 2018, SRP increased pumping from 150,000 to 200,000 acre-feet. This precautionary measure was one reason the system remained nearly half full during that period.

The goal is to preserve year-over-year storage in our reservoirs, while minimizing the use of groundwater necessary to mitigate extended droughts.

Protecting Arizona’s water together

Managing the Valley’s water resources is a big job and one we can’t do alone.

That’s why we’ve partnered with Valley cities, the Central Arizona Project and the Arizona Department of Water Resources to help protect our water.

Collaborating to protect water rights

Maintaining and protecting the water rights of the Greater Phoenix area is an integral part of our water stewardship responsibility.

As part of this responsibility, we actively participate in:

• Rural water planning groups
• Regional water planning studies
• Water measurement activities
• New water supply development projects, such as the C.C. Cragin Reservoir

SRP and its shareholders have some of the most extensive senior water rights on the Salt and Verde river watersheds. We work to maintain those legal rights that protect the Phoenix metropolitan area's water supply.

In addition, we've pursued the following unique agreements that have added to the water supply:

• An agreement with the Gila River Indian Community designed to make several million acre-feet of water supplies available to water users in central Arizona.
• The SRP-CAP Interconnect Facility, SRP’s interconnect facility with the Central Arizona Project (CAP) canal system, increases flexibility and resiliency with our water supplies.