A Thin Film Could Reduce Reservoir Water Evaporation By 75 Percent
Blog Entry by Gina-Marie Cheeseman in Environment and Climate Change
Wednesday, March 19, 2014 - 5:30pm
In the midst of a drought, every bit of water conservation helps. Moshe Alamaro, a Massachusetts Institute of Technology researcher, just might hold the key to reducing evaporation of reservoir water. Alamaro formed a startup company, based in Cambridge, Massachusetts, called More Aqua, Inc. to develop a monolayer film made from material extracted from vegetable oil, which would be put over a reservoir’s surface. The monolayer film can reduce evaporation up to 75 percent.
In dry climates, reservoir water evaporation losses can be equal to or even greater than 50 percent of the surface water supply. MAI wants to develop what it terms a “commercial sized pilot demonstration” on a reservoir in California that provides water to San Francisco. Alamaro reportedly reached out to the managers of the San Francisco Public Utilities Commission, but they have not yet given MAI the green light to go ahead with the pilot project. The pilot will cost an estimated $4.5 million and its development and demonstration is expected to last for two years.
Monolayers are not a new thing and scientists have long tried to develop ones that can handle winds. MAI’s technology has been proven in the laboratory to control the film in weather conditions such as high wind and turbulence. That is important because wind blowing the monolayer to the other side of the reservoir makes it useless. The worldwide market for evaporation suppression is an estimated $10 billion a year. California is one of the largest markets for evaporation suppression, as MAI notes.
California is currently going through a severe three-year drought. Last year ended as the driest year in recorded history for many areas of California and 2014 is not expected to receive much more rain. In January Governor Jerry Brown declared a drought state of emergency. At the end of January, the Department of Water Resources (DWR) announced that water agencies who receive water from the State Water Project will not receive any allocations this year. That is the first time that all SWP customers received a zero allocation announcement. Twenty-nine public water agencies buy water from the SWP to deliver to 25 million Californians and 750,000 acres of farmland.
The DWR also told water rights holders in the Sacramento Valley that their water allocations may be reduced to 50 percent, depending on future snow survey results. A snow survey taken during the end of February revealed that the statewide snowpack water equivalent continues to be low for the third year in a row. The snowpack water equivalent was only 24 percent of the average for this time of year. A snow survey on January 30 found the water content to be only 12 percent of average for late January. As a result of the lack of snow and rain this year, California’s major reservoirs are very low. One of those reservoirs, the Hetch Hetchy Reservoir, which supplies water to San Francisco, is only at 51.5 percent of maximum storage capacity.