Shall we limit evaporation with shade balls ?

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via Twitter/ pour me coffee

Do the “shade balls” actually save water? Maybe we need a life cycle analysis

by Lloyd Alter

All the blogs are excited about the shade balls being poured into a Los Angeles reservoir to save water being lost through evaporation. Brad Plumer of VOX writes:

The black plastic balls help maintain water quality by blocking sunlight, thereby preventing hazardous reactions with the chlorine and bromide in the water. (The shade balls also cut down on evaporation, though this is a relatively minor benefit.)

The mayor of LA stresses the water savings in a press conference.

By reducing evaporation, these shade balls will conserve 300 million gallons of water each year, instead of just evaporating into the sky. That’s 300 million gallons to fight this drought.

300 million gallons of water saved. But how much water did it take to make those balls? How many other resources? The balls are four inches in diameter, and made from polyethylene plastic by XavierC.  I could not find out how much they weigh, but Bloomberg Business says 96 million of them are being dumped into the reservoir.

Read the full article: Treehugger


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Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.