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  • Writer's pictureSophie Price

Shade Balls: Virtue or Vice?

Written by: Sophie Price

Edited by: Kyra Odell

As California is now steadily emerging out of years of struggling with drought, we can now look back and assess the strategies that the state used to save precious water. Among the odds and ends the state employed to mitigate the region’s water crisis for much of the 2010s, one of the more unique methods employed was their use of ‘shade balls’. After a video of the little black balls spilling into the Los Angeles Reservoir went viral in 2015, the public received them with mixed opinions – especially environmentalists.

The Los Angeles department of water and power (LADWP) affirms that the shade balls are a necessary investment to save water by reducing the evaporation of the reservoir by 85 to 90 percent during a drought. Furthermore, experts from LADWP claim that the annual savings could amount to up to 300 million gallons of water, which would be enough to supply drinking water to 8,100 people (Grennell 2018).

Despite the County’s claims to be protecting the integrity of Southern California’s water supply, could these plastic balls be doing more harm than good? Aside from the obvious environmental concerns they pose, when comparing the realities of their effectiveness to the expectations the LADWP set for them, there are slim margins of net benefit. In a press statement released after the introduction of shade balls into the aquifer, experts from LADWP claim that the $34.5 million investment into the city’s water quality is the most “cost effective” means of reducing water loss, estimated to be saving $250 million when compared to other comparable tools. They further remark that the genius of this project lies within the ability of the shade balls to save an estimated 300 million gallons of water a year from evaporating (LADWP 2015).

This project may seem like a very positive thing, and, yes - the shade balls have since been proven to be effective at preventing evaporation. But even so, on balance the 300 million gallons of water a year these plastic balls are intended to save is not very much when compared to other water usage habits that the state engages in – especially the amount of water used by industry and agriculture. Oil fracking alone uses an estimate of 2.14 million gallons of freshwater in California a day. Furthermore, if California’s agriculture industry cut its water use by only 5 percent, that would save 500 billion gallons in only a few months (Herzog 2015).

The production of these plastic balls have actually since been proven to be counterproductive to their intended agenda of saving water. In 2018, a team of researchers from MIT conducted an analysis on how much water was used to manufacture this project. They found that it takes more water to make the plastic balls than what they save, remarking that they would have to be sitting on the LA reservoir for over 2 years to offset this loss (Grennell 2018). Being made of high density of polyethylene (plastic), the balls require oil, natural gas, and electricity to be produced – all of which require copious amounts of water and contribute to environmental degradation as a result of fracking. The researchers further estimated that manufacturing the 96 million shade balls (not including any other bodies of water using the same technique), “required between 66 and 766 million gallons of water,” which they equated as being similar to “100 to 1,000 Olympic-sized swimming pools” (Grennell 2018).

Aside from the issue of water conservation, the use of shade balls have deeper large-scale implications for our environment. We have already discussed the environmental concerns that surround the initial manufacturing of the plastic, but there are additional considerations to take into account in regards to the ecological consequences of plastic within water sources. Dr. Max Liboiron, an expert in marine plastics, has outlined various negative impacts of introducing plastics into aquatic environments. Among the most concerning effects, he explains that leaching chemicals and micro-plastic fragments into the water supply is the most concerning. Despite HDPE plastic being considered a fairly safe plastic, the balls contain carcinogenic chemicals to make them UV resistant. This will doubtlessly result in this chemical leaching into the water supply. Liboiron explains that in general, “most plastics leach endocrine disrupting chemicals that interfere with animal and human hormone systems”, with some endocrine disruptors, such as bisphenol A (BPA), breaking down naturally in water after a few weeks or months. Most don’t, and the majority of water treatment systems don’t effectively remove these kinds of harmful chemicals from water (Liboiron 2015). Furthermore, the tiny fragments of micro-plastic that seep into water are smaller than a grain of rice. The plastic balls in the aquifer have a high potential to release microplastics that will make their way into runoff groundwater, drinking water, and agricultural practices, which will then be consumed by the public (Herzog 2015; Liboiron 2015).

It is important to remember why this all matters. This case in particular further reflects the current trend that the scales of current problems in relation to the scales of their proposed solutions are askew – shade balls seem to cause more issues than solve them. In the aftermath of leading the research study on plastic production at MIT, Erfan Haghighi expressed that people ought to “consider environmental conservation on a global scale, rather than just a local one” in the way that it is necessary to “consider the entire life cycle of the technology” (Grennell 2018). In other words, they may be saving water for use in California, but in doing so they use precious water from other areas of the world, degrade other environments through the manufacturing of plastics, and contribute to greenhouse gas production. If saving water from the Los Angeles Reservoir comes at the cost of environmental well being in other parts of the world, would it still be worth the effort?



Grennell, A. (2018, July 16). Why 96 million plastic “shade balls” dumped into the LA Reservoir may not save water. PBS NewsHour; PBS.

Herzog, K. (2015, August 19). Why shade balls aren’t such a great idea after all. Grist.

Liboiron, M. (2015, August 16). LA’s Shade Balls: The ecological costs of plastics in water. Discard Studies.

Los Angeles Department of Water and Power . (2015). Mayor Garcetti Announces Completion of Innovative “Shade Ball” Cover Project at Los Angeles Reservoir.

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