The City of Los Angeles has just finished spending $34.5 million on 96 million 'Shade Balls' which are 4 inch black HDPE balls that form a floating cover on liquid surfaces. The City and their manufacturer are claiming that 300 million gallons of water will be saved from evaporation each year but they present absolutely no data to verify those claims. The City experiences roughly 70-100 inches of surface water loss annually due to evaporation. 'Shade Balls', being black HDPE and a partial cover, retain 80% more thermal energy and conform to S. Assouline's findings from 2010 on the efficiency of partial covers. Those findings cite decades of evaporation studies that clearly explain how evaporation works and why temperature, or thermal energy, is the most important variable for predicting actual evaporation rates. 'Shade Balls' were not designed with an understanding of how evaporation works. 'Shade Balls' were designed to be cheap; black HDPE is one of the least expensive and most commonly used resins in plastics manufacturing. It seems that Mayor Eric Garcetti and the LADWP are satisfied with their lack of basic evaporation understanding because of reassurances from their vendors XavierC LLC, Microdyne Plastics, Orange Products, and ECC LLC that their "tested" black balls "come with the added benefit of reducing evaporation off the reservoir surfaces by 85 to 90 percent." But they don't. Additionally, if 'Shade Balls' suppress 300 million gallons from evaporating as is claimed, then Los Angeles must also be evaporating over 14 ft. from reservoir surfaces and experiencing average temperatures of over 90 degrees Fahrenheit annually (U.S. Climate Data says it's closer to 63.8 degrees). But they aren't. With 70-100 inches of evaporation, a white floating ball cover could suppress between 126 million and 183 million gallons of water from evaporating each year with 90% efficiency. Black 'Shade Balls' are only 50-70% efficient due to their high solar energy retention which increases the evaporative energy of the hyperbolic diffusion streamlines of water vapor. Los Angeles' 'Shade Balls' will only prevent a maximum of 141 million gallons from evaporating each year but may only suppress as little as 70 million gallons from evaporating at higher temperatures. Those are the facts, backed by published science, publicly available on the internet. What if I told you a white cover was on the market for almost half the cost and twice the performance (www.hydroorb.com)? What if Los Angeles did their homework on this project (they'd save $15.3 million and save more water). Do your research. Share this information. Let me know if I can provide any citations.

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The City of Los Angeles has just finished spending $34.5 million on 96 million 'Shade Balls' which are 4 inch black HDPE balls that form a floating cover on liquid surfaces. The City and their manufacturer are claiming that 300 million gallons of water will be saved from evaporation each year but they present absolutely no data to verify those claims.

The City experiences roughly 70-100 inches of surface water loss annually due to evaporation. 'Shade Balls', being black HDPE and a partial cover, retain 80% more thermal energy and conform to S. Assouline's findings from 2010 on the efficiency of partial covers. Those findings cite decades of evaporation studies that clearly explain how evaporation works and why temperature, or thermal energy, is the most important variable for predicting actual evaporation rates. 'Shade Balls' were not designed with an understanding of how evaporation works. 'Shade Balls' were designed to be cheap; black HDPE is one of the least expensive and most commonly used resins in plastics manufacturing.

It seems that Mayor Eric Garcetti and the LADWP are satisfied with their lack of basic evaporation understanding because of reassurances from their vendors XavierC LLC, Microdyne Plastics, Orange Products, and ECC LLC that their "tested" black balls "come with the added benefit of reducing evaporation off the reservoir surfaces by 85 to 90 percent." But they don't. Additionally, if 'Shade Balls' suppress 300 million gallons from evaporating as is claimed, then Los Angeles must also be evaporating over 14 ft. from reservoir surfaces and experiencing average temperatures of over 90 degrees Fahrenheit annually (U.S. Climate Data says it's closer to 63.8 degrees). But they aren't.

With 70-100 inches of evaporation, a white floating ball cover could suppress between 126 million and 183 million gallons of water from evaporating each year with 90% efficiency. Black 'Shade Balls' are only 50-70% efficient due to their high solar energy retention which increases the evaporative energy of the hyperbolic diffusion streamlines of water vapor.

Los Angeles' 'Shade Balls' will only prevent a maximum of 141 million gallons from evaporating each year but may only suppress as little as 70 million gallons from evaporating at higher temperatures.

Those are the facts, backed by published science, publicly available on the internet.

What if I told you a white cover was on the market for almost half the cost and twice the performance (www.hydroorb.com)? What if Los Angeles did their homework on this project (they'd save $15.3 million and save more water).

Do your research. Share this information.

Let me know if I can provide any citations.