Approved by the Energy, Environment, and Water Policy Committee on March 14, 2019
Approved by the Public Policy Committee on April 28, 2019
Adopted by the Board of Direction on July 13, 2019
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. Economic feasibility for desalination projects should be consistent with other water supply projects. The public, legislators and regulators should be educated on desalination processes, its costs and benefits. Research on improvements in desalination technology techniques for the environmentally safe disposal of by-products and environmentally responsible intake systems should be continued.
Issue
Over the last few decades, desalination has been increasing throughout the world to produce drinking water from seawater and saline or brackish water and to improve the quantity and quality of supplies of fresh water for domestic, agricultural, and industrial purposes. There are thousands of desalination plants worldwide. Currently the process can be energy intensive and can have adverse environmental impacts if not sufficiently mitigated.
As water use increases and the availability of renewable supplies decreases, the cost of developing new supplies of surface and groundwater increases consequently the use of desalination may increase. In some areas, based upon lifecycle analysis with sustainability principles, it may be more cost effective to desalt saline or brackish waters than to develop new supplies of fresh water. In inland areas, the 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 application of desalination technology in these regions. Due to desalination energy requirements, project planning will often benefit from the inclusion of renewable energy components.
Rationale
One of ASCE's objectives is to promote new methods and technologies that sustain or improve the quality of life. The world's water resources are being stressed by increasing demands. Desalination technologies, including environmentally responsible concentrate management, may enable certain areas to meet water demands. Civil engineers are involved in developing effective technologies such as desalination and by-product disposal to augment potable natural water resources.
This policy has worldwide application
ASCE Policy Statement 407
First Approved in 1993