Approved by the Energy, Environment, and Water Policy Committee on February 17, 2022
Approved by the Public Policy and Practice Committee on May 18, 2022
Adopted by the Board of Direction on July 22, 2022
Policy
The American Society of Civil Engineers (ASCE) recognizes that desalination of saline or brackish waters and seawater can be an alternative source for potable water. Evaluation of the technical and economic feasibility for desalination projects should be consistent with other water supply options. Additional education on desalination processes, costs, and benefits should be provided to the general public, legislators, and regulators. Research on improvements in desalination technology techniques for the environmentally safe disposal of concentrate (brine) and the application of environmentally responsible intake systems should be continued and supported.
Issue
The use of desalination has been increasing throughout the world to produce fresh water for domestic, agricultural, and industrial purposes. Currently there are over 16,000 operational desalination plants located in 177 different countries producing 25 billion gallons of fresh water. The United States has over 1,400 operational desalination plants alone. There are thousands of desalination plants worldwide. The desalination process, however, can be energy intensive, expensive to operate, and it can have adverse environmental impacts if not sufficiently mitigated.
With the growth in global water demand, current supply sources can become limited and the cost to provide new supplies of surface and groundwater can be costly. Consequently, the application of desalination processes can become more economically attractive. In some areas, based upon lifecycle analysis with sustainability principles, it may be more cost effective to desalinate saline or brackish waters than to develop new supplies of fresh water. In inland areas, desalination of saline or brackish waters may be essential for the continuation of a regional economy, but the economic, technical, or environmental constraints associated with concentrate disposal may hinder the use of desalination technology. Due to desalination’s energy requirements, projects can incorporate and benefit from the inclusion of a renewable energy source.
Rationale
One of ASCE's objectives is to promote new methods and technologies that sustain or improve the quality of life, and civil engineers engage in this by developing and implementing effective treatment processes such as desalination. The world's water resources are being stressed by increasing demands. Desalination technologies, including environmentally responsible concentrate management, have the potential to may enable certain areas to meet growing water demands.
This policy has worldwide application
ASCE Policy Statement 407
First Approved in 1993