What are the drawbacks of desalinating water?

Desalination creates heavily salted brine, which can harm sea life. Desalination also can leak the chemicals used into the "clean" water, resulting in health issues in the humans that drink it. The most effected sea life by the brine released by desalination would be plankton and photoplankton, which take damage from this.
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Sequoia national park  /  inyo national forest, california, u.s. mount whitney is the tallest mountain in california, as well as the highest summit in the contiguous united states and thesierra nevada—with an elevation of 14,505 feet (4,421 m).