Water and Arizona’s Future

By Karl Reiner

The water level in the Colorado River’s storage lakes has been steadily dropping, leading to the possibility that Tucson will face a water shortage in the future.  As consumers of local ground water and supplies from the Colorado, we need to start paying attention to the problem.  The combined effects of population growth, drought and global warming trends are turning the region’s water future murky.

 

A recent government report on climate change states that global warming has already brought about some climate modifications.  Man-made pollution composed of greenhouse gas emissions was found to be the main cause behind higher average temperatures in the Midwest.  The increased warming has extended the growing season by a week. It also caused more frequent heavy rain storms.

 

The report warns that these changes are only the beginning.  We will face more serious consequences if emissions are not restricted.  If the warming trend is allowed to continue, temperatures across the U.S. are projected to rise by 4 to 11 degrees by 2100.  As the temperature rises, some areas such as Arizona will become drier. 

 

In the United Kingdom, worried scientists want to undertake research to find ways to reverse the global warming process. If the world’s governments can’t agree on programs to curb greenhouse gas emissions, they want to start developing technologies that can remove carbon dioxide from the atmosphere and reflect sunlight back into space.

 

A normal summer monsoon delivers about six inches of rain to the Tucson area.  As has often been the case in recent years, this year’s monsoon rains fell short.  Rainfall was about half of the amount that should have fallen during the June to September season.  At the end of September, precipitation in most of the metropolitan area was three inches below normal.   

 

This year’s failed monsoon may be a continuation of the drought that has been plaguing Tucson for 10 years.  Some weather observers believe the drought could drag on for another 20 years. They see evidence linking the current dry period to a reoccurring drought pattern that has come and gone for the past 1,000 years. It is believed that the warming trend brought by climate change could worsen the drought pattern. 

 

Drought has upended societies in the past.  It was a factor contributing to the decline of the Hohokam culture in the early 1400’s.  Prior to its demise, Hohokam society had developed fairly sophisticated irrigation and farming techniques.  The structural ruins that remained after the Hohokam disappeared impressed and puzzled the early Spanish explorers as they traversed the region.

 

The $3.6 billion Central Arizona Project (CAP) is designed to deliver 1.5 million acre-feet of Colorado River water per year from Lake Havasu to Pima, Pinal and Maricopa counties. (An acre-foot of water equates to 325,851 gallons.)  Water travels a distance of 336 miles through a system terminating 14 miles south of Tucson. 

 

When the Colorado’s water was liberally allocated to the using states, very little was known about reoccurring drought patterns and the effects of climate change.  If runoff in the Colorado River’s watershed continues to decline, water deliveries will have to be reduced.  Depending on the severity of the drop in runoff, planners believe deliveries to Phoenix and Tucson might have to be reduced by a third or half in the future. 

 

While there is disagreement among the experts as to the causes, timing and severity of the looming water shortage, there is a general consensus that Colorado River water will be increasingly in short supply as time goes by.  Some scientists believe that if the current trend holds, the Colorado could be running extremely low by 2050.   

 

Due to the lack of recharging rains, Tucson’s groundwater supplies will also diminish.  As overall water availability declines, we will have to start looking to the costly solutions other nations have implemented.  One country that has been dealing with water problems for years is the Kingdom of Saudi Arabia. 

 

About the size of the United States east of the Mississippi River, Saudi Arabia is home to one-fifth of the world’s proven oil reserves.  The ample store of oil ensures that the Kingdom will remain among the world’s top oil exporters for the foreseeable future.  Although the country can be said to be floating in oil, it is short of water.  Being more arid than Arizona, securing a stable water supply has always been a concern.

 

To meet the country’s needs, Saudi Arabia has been seriously investing in desalination technology since the late 1970s.  Over time, it has become the world’s largest producer of desalinated water, accounting for 26% of world production.  There are 30 desalination plants in operation on Saudi Arabia’s Red Sea and Persian Gulf coasts.  To meet future demand, Saudi Arabia is expected to invest $90 billion in water and sewage systems over the next 20 years.

 

One of the world’s largest desalination plants is located at Jubail on Saudi Arabia’s Persian Gulf coast. The massive complex produces 50% of the nation’s drinking water.  The plant supplies two pipelines that move desalinated water 290 miles inland to Riyadh, the capital.

 

The Jubail-Riyadh system of pipelines and pumping stations delivers 210 million gallons of water per day.  Since Riyadh, with a population of approximately six million, suffers severely from declining ground water sources, the water from Jubail has become vital to the city’s ability to function.

 

If the dire predictions of a water shortage come true in southern Arizona, our closest source of ocean water is less than 200 miles away, along the coast of the Gulf of California in Mexico’s state of Sonora.  If we have to start scrambling to get salt water processed and delivered to Tucson’s taps, our water utilities will be rushing to participate in joint ventures in Mexico to build the desalination plants and pipelines needed to serve Sonora and Arizona.

 

With the cost of desalinated water running about 10 times the cost of current supplies, our water use habits will drastically change.  We will stop taking water for granted and have to treat it as a finite resource.  The massive increase in price will focus attention on conserving and reclaiming every available drop. 

 

Unlike the Hohokam, we will have access to technology that can help prevent a disaster.  While expensive desalination technology can provide for urban needs, it cannot support much agriculture.  As a consequence, a drying climate will bring massive changes to Arizona’s economy.  Regrettably, much of the change will not be good.