Protecting our water supply

Our water supply is a very precious resource, especially because we live in a desert. At SRP, our goal is to manage our water supplies to make sure we have enough for both current and future generations. 

We’re managing SRP’s water supply system to take on its biggest threats: 

• Loss of system storage capacity 
• Drought 
• Changing climate 

Where does Phoenix get its water from? For more than 100 years, SRP has managed the water from the Salt and Verde rivers, bringing in more than half of the Valley’s water supply. 

Our water supply is ready to weather climate change

According to a recent U.S. Bureau of Reclamation study, the Salt and Verde rivers’ water supply is less likely to be impacted by climate change than the Colorado River system. 

Why is that? Because of two main factors:

• Location 
• Timing of snowmelt 

Maintaining our water supply  

Typically, Arizona only gets 7 or 8 inches of rain a year. We depend on snowmelt runoff from the forested watershed up north to feed our water supply.  

A watershed is an area of land that channels rainfall and snowmelt to creeks, streams and rivers to be stored in the state’s water reservoir systems.   

Before it really heats up in Arizona, the Salt and Verde river systems are fed by snow that melts in March and early April. The cooler temperatures during that time of year means less water evaporates and as a result, more water makes its way into SRP’s reservoirs and lakes.  

Comparatively, the Colorado River system is fed by snowmelt in the warmer months of May and June. Since it’s hotter during those months, more water evaporates and so less water is available to feed the river. 

Maintaining our water supply 

To create a water supply that’s large enough to meet the Valley’s needs, we need a robust system of storage locations and water sources. This is what we call our water infrastructure system.   

In addition to the reservoirs, SRP’s water system infrastructure enhances the reliability of our water supply. The system includes:  

• Underground water storage facilities  
• A groundwater well system that sustainably withdraws water from SRP aquifers    
• Connection to the Central Arizona Project (CAP) Canal and Colorado River water supplies   

Did you know? In addition to storing water, underground water storage facilities help to protect underground aquifers and allow us to grow how much we can store.   

Even though it’s enough water for now, we are always preparing for an uncertain future.   

How we stay prepared  

While we hope for the best each year, we plan for the worst. Because rain and snowfall are unpredictable, we manage our water resources every year as if we’re heading into a drought.   

In fact, SRP reservoirs, or lakes, have more than 1 trillion gallons of storage capacity. Maintaining storage capacity is vital in case of droughts and floods.  

To better understand the Salt and Verde water system’s sensitivity to climate change, we’re continuing our research work with a few universities and partners.  

This includes Arizona State University, the University of Arizona and Northern Arizona University. We also utilize SRP’s infrastructure to improve the water situation in the region by helping others on an ongoing basis.  

You can help protect our water supply

In fact, you already have! Our research shows that SRP’s reservoirs are in good shape partly because the Valley has been conserving more water.    

According to AZ Central, Valley cities, including Phoenix as the fifth-largest city in the nation, are using less water. This is credited to the cities’ dedication to water conservation programs and education.   

See how you can become part of our culture of conservation. Every drop we save today is one more we can store for tomorrow.