A major benefit of the Groundwater Replenishment System, Deshmukh and his colleagues explained to local residents, is that injection into groundwater can address one of the biggest sources of water loss.
The majority of Earth’s liquid freshwater is found in lakes. To ensure an ongoing freshwater resource, communities often invest in dams. These barriers stop the flow of rivers and create reservoirs, large bodies of water that hold freshwater for a variety of uses (freshwater source, flood control, electricity production). In Canada and the United States, these often become recreation sites and fishing resources. While reservoirs are a valuable resource, they lose an enormous amount of water every day through evaporation.
Depending on temperatures, atmospheric conditions, and the surface area of a reservoir or lake, wide-open bodies of water can evaporate tens of thousands of litres of water a day in desert settings where it’s hot and dry. The California Department of Water Resources calculated that fresh-water reservoirs in the South Coast region lost more than 200 million cubic metres to evaporation in 2000 alone. Worldwide, reservoirs lose more water to evaporation than that used for industry and domestic purposes combined.
The construction of dams can also spark political conflicts. In the Middle East, Turkey’s plans to build 22 dams that pull water from the Tigris and Euphrates rivers for agriculture and electric power will impact its neighbours Syria and Jordan downstream. With too little water available for too many people, this hotspot may be the site of future conflict. Similarly, a proposal to build two new dams on the Churchill River in Labrador to provide electricity to Newfoundland, and potentially as an export to the United States, is being met with opposition by residents and native Inuit who counter it is not worth the destruction to the natural area that the dams will cause.
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