Tucson Arizona's Water Problems

We live in the Sonoran desert...we need to know how to preserve precious water. The amount of water used by Tucson and its surrounding area is 114 billion gallons a year. City dwellers and farmers use the majority, while a smaller amount is taken by local mines. Golf courses account for slightly more than 5 percent of the total water use. As our areas grow, and water needs change, we must be aware of this precious resource. We live in a very arrid place and we need to be thinking of our water supply. Eight of the past nine years have been unusually dry, and Arizona experienced its sixth consecutive dry winter in 2003-04.

Most of this water comes from natural aquifers under the city. Other sources include recycled sewer water and supplies from the Central Arizona Project. The pumping of groundwater has led to several problems. The aquifers are draining at nearly three times the rate that they are being recharged through natural processes. Over the years, the city has had to dig deeper wells, costing money and delving into the bottom of the aquifers where the water contains more minerals and other particles. As a result of this, central Tucson is sinking at the rate of an eighth of an inch a year. Local rivers are also drying up. The Santa Cruz used by Native Americans and early pioneers for fishing and irrigation, now stands empty most of the year.

Tucsonans face very hard choices if they want to achieve a sustainable water supply. There will be hard choices about who will have to bear the burden of water efficiency. The Central Arizona Project, which imports water from approximately 136,000 acre-feet of the Colorado River, was hailed as the solution to Tucson's supply problems when it was completed in 1990, but high costs kept most mines and farms from using the project. In 1992, CAP water was delivered to municipal pipes. Customers complained of murky water that corroded pipes, damaged swimming pools and killed their pet fish. Complaints poored in, and by 1995, the city had paid more than $1 million in damages. Voters passed a ballot to halt the use of CAP water for the city the same year. Recycled wastewater has had more success. The majority is released into the Santa Cruz River channel, where it trickles into the aquifer and is used for irrigation, parks, and golf courses. At the moment, the majority of water used for those purposes is drinkable ground water. Two-thirds of the water sprayed onto golf courses is treated drinking water. Since May 3, 2001, we've been fortunate to have an additional water supply from the Clearwater Renewable Resource Facility west of the Tucson Mountains that helps us make it through the high-demand Summer months.

Tucson Water is now pumping Central Avra Valley Storage and Recovery Project (CAVSARP) water along with groundwater from four well fields (200 groundwater wells) that are located in and around the Tucson metropolitan area. In urban Tucson, most of the wells (also known as Points of Entry or POE) serve the neighborhood in which they are located, with excess supply routed to reservoirs for use elsewhere in the system. Whenever the demand for water exceeds the amount of groundwater being pumped from wells, the excess is supplied from Tucson Water's reservoirs. Reservoir capacity is 240 million gallons available in 48 reservoirs scattered throughout the Tucson Water service area. Reservoirs help balance water pressure. They provide opportunities to move water where it's needed in the system. At the end of 2003, the blend Tucson water delivered was about 85% native groundwater and 15% recharged Colorado River water. Over time, it will contain an increasing percentage of recharged Colorado River water.

Pollution is another problem. Runoff from rain introduces pollutants from the surface into the aquifers. Contamination from Hughes Aircraft, now owned by Raytheon, led to high levels of the industrial solvent Trichloroethylene(TCE), which is suspected of causing cancer and liver problems. The contaminated water is currently being treated by the Tucson Airport Area Remediation Project(TARP) and then mixed with the municipal water supply. TARP was developed in order to clean and make beneficial use of water contaminated with TCE, by removing the solvent. The TARP plant treats approximately 6.2 million gallons of water per day. During 2003, this plant treated a total of approximately 2.25 billion gallons of water.

Our conservation efforts will allow the water table to continue to recover from decades of groundwater overpumping and, over time, may even contribute to the recovery of some of Tucson's river bank areas. Tucson Water customers can make common sense decisions and create water savings both indoors and out. Desert adapted landscaping, proper use of drip irrigation, water smart indoor fixtures, and making wise water use choices - all of these ingredients add up to a recipe for water use reduction. We call it Beat the Peak, during the summer months. Daily water demand doubles during these months. More than 60% of the water used during this season is used outdoors. Tucson Water's daily water demand is influenced primarily by two factors: high daily temperature and rainfall. Rainfall plays an important role in daily water demand, particularly during the summer months. Even the hint of rain with summer monsoon thunderclouds will cause a significant drop in water demand, although, our community only receives seven inches of rainfall a year and we use the equivalent of 36 inches of water every year.

In 2003, Tucson Water delivered up to 36 million gallons a day of blended water to about 675,000 people in the Tucson area, and that rose to 54 million gallons a day by the end of 2004. This critical new supply has allowed us to turn off more than 60 wells in the Central Wellfield. The only way to ensure that these wells remain on standby is through conservation. Tucson Water customers play a critical role in determining daily water usage. Residential, commercial, and industrial customers are encouraged to do all they can to make conservation a habit. If every Tucson Water customer made a change which produced one gallon in savings each day, the total effort would result in an annual reduction of more than 235 million gallons. Most of us are able to make that one gallon savings choice. Commercial and multi-family customers, whose outdoor water use is higher, have even more of an opportunity to reduce their water use by making sure they properly maintain their irrigation system and use efficient water management strategies. Conservation efforts add up to big savings for everyone. We need to start helping to conserve water supplies and protect the diversity and quality of life in the desert environment, today.