Water Supply Q & A

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​​​​Phoenix's water supply is good, but it is important to conserve water as a lifestyle. It's everyone's job to think about water…every time you use it…and use it responsibly. Phoenix has the water it needs - but none to waste.

What is the status of Phoenix's water supply?

Phoenix's water supply is in very good shape. Even though Phoenix remains in a regional period of climatic drought that began in 2000, our water supply is not dependent on annual precipitation events.  Our water supply originates as snow pack far north and east of the Valley that melts and flows into vast reservoirs that store it for delivery during low-flow years .  

From where does the city of Phoenix get its water?

The city of  Phoenix 's water supply comes primarily from the Salt River Project (SRP) which brings water by canal and pipeline from the Salt and Verde Rivers , and the Central Arizona Project (CAP) which transports Colorado River water. A small amount of Phoenix's supply comes from wells, or groundwater.  Phoenix also uses a portion of its reclaimed effluent to maintain parks and for recharging local groundwater aquifers.

How can Phoenix 's water supply be so good, when I keep hearing about drought and other areas that are considering water restrictions?

Phoenix has had a hundred years of sure-handed water management. Extremely wise planning for drought in the desert and the fact that we have several water sources has kept Phoenix way ahead of the drought curve for decades. Phoenix diversified its water portfolio long ago and amended the city code to promote reuse of water and water conservation​

Are mandatory water use restrictions coming soon? What happens to our water supply if drought continues for a long time?

Even though it is usually dry in the Valley, Phoenix will not need to impose mandatory water use restrictions in the foreseeable future. If, during the next ten-to-fifteen years, the west were to experience widespread drought conditions that are as bad or worse than we’ve seen over the past fifteen years,, the reduction of available water supplies on the Colorado and Salt/Verde Rivers may reach a point where Phoenix would initiate mandatory water use restrictions that go beyond our traditional low water use lifestyle. This gives everyone time to start preparing for such an event. Continued wise planning and water conservation remain big parts of ensuring our future water supply, especially if the regional drought lasts for a long time. Phoenix will have the water it needs, but none to waste…with your help​.

What might some future water restrictions be?

If we reach a point where drought restrictions are required, these restrictions would be phased to become increasingly severe as drought continues. Initially these restrictions would focus on outdoor water use and water waste. Restrictions might include watering on certain days, banning the use of outdoor water features, and stringent enforcement of water wasting laws. More severe restrictions may include using child safe pool covers to reduce evaporation, banning turf irrigation (letting lawns go brown), and banning car washing. Phoenix would only ask you to implement such drastic measures if it is really needed to protect the public health and safety. We will give you plenty of notice and we will end restrictions as soon as we can to make as little impact on your life as possible.

However, there are things you can do now to prepare for water use restrictions and lessen the impact. Zone your irrigation so you can turn water off to your turf and flower beds and still water your trees and shrubs. Be prepared to turn off outdoor water features - like fountains. If you are building a new pool or rehabbing an old pool, include the hardware needed to install a child safe pool cover. And, if you are replacing water using appliances, pick the most water efficient ones, along with low flow toilets and faucets.

Does Phoenix have a drought response plan?

Yes. It is called the Drought Management Plan and it is part of Phoenix City Code (Chapter 37, Sections 121 through 130.2). The Drought Management Plan is implemented when Phoenix projects that the available water supply may not meet total customer demand. The plan identifies varied levels of voluntary and mandatory conservation measures, education, possible usage restrictions, and possible surcharges, as well as possible bans and penalties for misuse of water. Download or read the 2021 Drought Management Plan​. For additional information about the drought plan,  email the Water Services Water Resources and Conservation Office .

Do other cities or the state of Arizona have drought plans?

Yes.  State statutes established in 2005 require drinking water providers to develop water supply, conservation and drought plans.   In addition, the State has developed an Arizona Drought Prepa​redness Plan. The principal​ intent of the Arizona D​rought Preparedness Plan was to establish a flexible framework to refine the State’s drought monitoring process, its understanding of drought impacts, and the mechanisms for limiting future vulnerability. The plan was adopted in 2004 and its continued implementation was ordered in 2007 (EO2007-10).  The Arizona Department of Water Resources prepares an Arizona Drought Preparedness Annual Report that covers the drought conditions and preparedness activities for the water year.​

 What is Phoenix doing to insure our water supply for the future?

Phoenix plans its water supply for 50 to 100 years into the future. Along with monitoring usage and working with its water partners, Phoenix continues to adopt effective water supply standards, improve groundwater capacity to supplement its surface water supply from snows, and expand the use of highly treated wastewater, or reclaimed water, which saves on drinking water. Reclaimed water is used for parks, enhancement of riparian areas, and recharging groundwater aquifers as well as the cooling towers at the Palo Verde power plant.

During years when adequate water supplies are available, the city also has been banking water. This is done by storing excess water in underground aquifers. During times of water restrictions, this water will be pumped back up and used as a supply to meet demand. Arizona is a leader in such water banking.

Phoenix was the first Valley city to adopt a Drought Management Plan (in 1990) and continues to enhance and update it as necessary. We also maintain a Water Resources Plan that is updated every five years and Water infrastructure Master Plans that are updated annually.

As part of the development of the Water Resources Plan, Phoenix rigorously analyzes drought scenarios that exceed the State's 100 year water supply requirement. This results in a robust Water Resources Plan that sets a high standard,  allowing us to better withstand long term drought. To implement this standard, Phoenix has initiated several programs, including enhancing its 25 year-old award winning water conservation public awareness program that urges residents and businesses to join Phoenix government by adopting a water conservation lifestyle. Phoenix has also initiated an effort to improve groundwater capacity. Currently, the city has substantial reserves of groundwater, but uses very little of it to meet customers' normal water needs. These groundwater reserves will play a critical role if our supplies from the Colorado , Salt and Verde Rivers are reduced as a result of long term drought. Additionally, Phoenix will expand its use of reclaimed water. Simply stated, Phoenix is working to ensure that our grandchildren can live in the desert even during times of long term drought.

Does lack of rain in the Valley have any effect on our water supply?

Rain in the Valley will help with irrigating grass, trees and plants, but it does not fill the reservoirs, which store water from snows north and east of the Valley, before sending that water to the city of Phoenix's treatment plants. And, if landscape watering systems are not turned off when it rains, there is no water savings. While Phoenix customers have increasingly adopted a low water use lifestyle over the years, people simply use more water when it doesn't rain in the Valley.

Why doesn't Phoenix just stop growth to save water?

Fortunately, meeting current and future water demands during times of drought does not require stopping growth in Phoenix . Our current economy relies on continued growth and most people in Phoenix and the region support policies that favor managed growth. We recently looked at the 50 year future of Phoenix and its ability to meet water needs of a growing city even under long term drought. Our conclusion was that new water facilities and supplies needed for growth could be met without having a negative impact on existing customers. Phoenix has moved forward with new policies that take this approach, such as requiring low water use for new construction. But existing customers must still do their part, increasing your efforts to live a low water use lifestyle will means that we will be able to supply you with water, even during drought, at the least possible cost to you.

New homes require new water resources, and Phoenix expects development to fund the cost of these resources. In addition, most new development utilizes low water use systems and landscaping, thus, the average household water use of a new house is less than the average household water use of houses built more than a decade ago. New commercial and industrial uses also are more efficient. The result is that in the city of Phoenix, the rate at which total water consumption is increasing is lower than our growth rate. Thus stopping growth would not result in significant water savings that would benefit current customers.

However, stopping growth could result in a drastic slow-down in the local economy; a slowdown that would hurt not only the home building industry, but the entire employment and commerce base that sustains our community. This would limit the city's ability to finance the development of new water resources and have a major impact on our ability to meet demand during times of drought..

I don't think I should have to pay for new customers' water, should I?

Phoenix uses developer's fees to help pay for new water infrastructure and supplies, so existing customers don't foot the bill for growth. 

Can the drought cause higher water rates?

Yes.  Drought could eventually affect our water rates in a number of ways.  For example, a reduction in Colorado River supplies may not impact water supplies available to Phoenix (due to our high priority for receiving water from the Central Arizona Project), but the cost for that CAP water could increase because fewer customers would be covering the base CAP operating costs.  In addition, costs for water will increase if the city needs to pump additional groundwater, purchase additional water supplies that may be available at the time, or hire additional staff to enforce mandated water restrictions. In the future, a drought surcharge could be imposed to charge people according to the amount of water they use each month.

Why is Phoenix's water supply so different from rural Arizona's supply?

Comparing Phoenix's water supplies to any other city's or region's supply is an apples and oranges comparison. The reliability of Phoenix's water supply is better than many rural Arizona areas because Phoenix has multiple water sources – surface water, groundwater and highly treated wastewater (for crops, parks, etc.).  More than 90 percent of our water supply is surface water that originates as snow in the mountains north and east of Phoenix.  As the snow melts, it flows into reservoirs on the Colorado, Salt and Verde Rivers where it is stored for future release to our water treatment plants.  These extensive reservoir systems allow for the capture of water during wet periods for use during the dry years.  Fortunately, Phoenix holds high-priority rights to the use of these surface water supplies, so they are extremely reliable.  In addition, over the past century, Phoenix has taken proactive measures to secure additional surface water rights (through various purchases, leases and infrastructure development projects), which further enhances our water supply position.

Other parts of Arizona rely more heavily on shallow groundwater supplies or low-capacity storage systems that are much more susceptible to dry cycles. Phoenix's foresight and use of surface, ground and reclaimed water, as well as smart water conservation efforts, allow for a redundancy of supply that protects our customers during times of drought.

Why doesn't Phoenix do something about golf courses and others who use a lot of water?

Golf courses and many other businesses, not only are vital to our economy, but they use some of the most highly advanced watering systems available. After all, they need to look out for their bottom line. Additionally, many Valley golf courses use non-potable water, such as non-drinkable well water and reclaimed water, which is highly treated wastewater, to water their turf areas. Golf courses are an asset that contributes heavily to the draw for tourism in the Valley, which, in turn, creates jobs and helps keep the economy healthy. In total, golf course water use constitutes less than three percent of total water delivered by the city of Phoenix .

Professional turf managers use real-time data to assess how much moisture is lost from turf areas each day and how much is put back. That same grass management data is available to all citizens. The Arizona Republic newspaper reports on water needs daily on the weather page, and there is a website to help you plan watering schedules for your lawn and plants. You can create a personal lawn watering guide by visiting the AZMET website. ​There also are a variety of materials available through the water conservation office which you can request electronically or by calling us at (602) 261-8367.

In the future, a drought surcharge could be imposed to charge people according to the amount of water they use each month.

Why should I save water when my neighbors and businesses use so much?

Water conservation is everyone's individual responsibility. It is true that there may be those who may not respect the fact we live in a desert and that was is a precious resource, we can only hope that eventually people will take water conservation advice to heart and do their part. 

I don't even live in the desert, why should I save water?

If you live anywhere in Phoenix or the Valley, you live in the desert. So, please, simply think about water every time you use it...and use it responsibly.

Will the drought get worse?

Research of climatic conditions indicates that droughts as long as 20 to 30 years have occurred several times over the last 1,000 years. Such droughts were characteristic of our current drought in that they covered the entire western United States and other parts of North America . Though we cannot predict how long drought will continue, we can assess how long it will take to recover from drought. In the west, normal climatic conditions include some years of below normal precipitation and some years of above normal precipitation. Low rainfall is normal. However, after an extended period of below normal rainfall, the soil moisture and reservoir storage deficits are not typically made up in one year. The U.S. Drought monitor website ​ provides information and forecasts on a weekly basis.

​What can I do to conserve water?

Simply Think About Water...every time you use it...and use it responsibly. You can prepare to live under more severe drought conditions. Outdoor water needs use more than sixty percent of our water. It is also the usage where restrictions can create the largest benefit, should they become necessary. There are a number of techniques which can help you prepare for more severe drought without adversely affecting your lifestyle or your pocketbook. For more information, see the   Water Conservation section of this website.

In general, the following steps can be taken to help conserve water:

  • Know how your landscaping or sprinkler timer works. Decrease watering a​​s weather cools or whenever it rains in your area.

  • Don't over-water native plants. Learn how much water they need and realize that they are desert plants and will die from too much water.

  • Plant grass only where children and pets use it, not just as a decoration.

  • Invest in a swimming pool cover to help prevent evaporation.

  • Sweep your driveway instead of hosing it down.

  • Don't fill your washing machine with water if you don't have a full load of clothes in it.

  • Run your dishwasher only when it's full.

  • Buy low-flow toilets and faucets when you replace existing ones.

 Where can I find out more?