Many new water treatment and management technologies are likely to advance rapidly in the years ahead, as communities explore creative ways to assure sustainable water resources.
Future water supply continues to be among the most critical short- and long-term issues identified in the annual American Water Works Association’s (AWWA) State of the Industry Report.
“We need broad coordination,” wrote one engineer from the western United States in the 2007 survey. “Water is a limited resource that must be managed cooperatively, including supply, quality, and regulatory issues.”
While utilities in arid climates such as the desert Southwest have long struggled with water scarcity issues, the big story this year is the drought in the Southeast. Lake Lanier for example, which supplies water to some three million people in the Atlanta area, reached historically low levels in 2007.
But drought is not the only issue threatening supplies. Shifting U.S. populations continue to put increased pressure on water resources in arid and semi-arid climates. People continue to relocate to places where water is simply not available to meet demands
In the coming decades, water systems can expect to spend time and resources on the protection of existing water sources, the development of new ones, and the optimization of utility operations to ensure a stable supply of safe water. As water suppliers seek out new sources, new technologies will play a key role, especially those used in water reuse and desalination.
While desalting technology has been around for many years, it has only become a viable choice for large-scale water treatment in the past decade in the United States. The most popular desalination treatment process is membrane-based reverse osmosis, which is the reversal of the osmosis process. In this process,pressure is applied to water, which allows freshwater to flow through a membrane, leaving the salts behind. The second
most popular form of desalination used in the U.S. is electrodialysis, which is a desalting process driven by an electrical potential difference between oppositely charged electrodes.
While desalination is most popular along the coasts, especially in Florida, California, and Texas, many inland cities are looking at desalination as well. Rather than desalting sea water, these inland desalination plants treat brackish water for drinking or nondrinking purposes.
Water reuse is the treatment of wastewater for a certain purpose. Most reclaimed water in the U.S. is currently used for industrial purposes or to supply water to golf courses or other agricultural destinations. This frees up capacity in a utility’s potable water supply for use by the general population.
Additionally, some utilities are designing dual systems in new communities to allow potable water to be delivered to residential and commercial properties for consumption, while reclaimed water can be used for irrigation purposes.
As the infrastructure in water utility’s distribution system ages, leaks can become more and more prevalent, wasting a large amount of precious water resources. This “nonrevenue water” as it’s called in the industry, is a liability because it not only removes revenue from the utility, but also can lead to expensive problems like sinkholes and damage to businesses.
Leak detection and repair technology may become increasingly important as utilities evaluate their asset management strategies in the coming years. Automated technologies are increasingly being used in leak detection. For example, some technologies use sonar to detect areas of stress or cracks in water mains. When a unit detects a leak, it sends information to receiver units carried by utility workers who patrol the system. Other technologies involve sending robotic units inside the pipe to detect leaks.
Automated Meter Readin
The ability to more accurately read water meters can help water utilities detect wasted water on the customers end. Sharp increases in water use can indicate a problem. Automated meter reading electronically reads customers meters from a central location. Data from meters are transmitted via telephone or cable television lines, wireless communications and even satellite systems to a central computer, where they are monitored by the utility. This type of monitoring allows utilities to detect major leaks on the customers’ end much more quickly.
On the consumer end of the spectrum, improved water efficiency fixtures are also likely to become more popular as communities feel the effects of strained water resources. The U.S. Environmental Protection Agency in 2005 launched a program called WaterSense, which will help consumers identify indoor and outdoor products that use water efficiently. Low-flush toilets, smart outdoor moisture sensors and a variety of other technologies will become increasingly common in new and retrofitted homes.
It’s clear that water resource challenges will continue to be a major driver for new technology development in the water industry. Water stewards from source to tap have a role to play in assuring adequate supplies for today’s and future generations. At each point in the process, new technologies will play a big role in determining the success of their efforts.
Jack Hoffbuhr is executive director of the American Waterworks Association, an international nonprofit scientific and educational society dedicated to the improvement of drinking water quality and supply. For information visit www.awwa.org.