You’re correct that the water isn’t actually wasted, per se. However, when wasting water, where it ends up usually isn’t somewhere readily available. Whether into the ground, which takes quite some time to become groundwater, or to a sewage treatment plant that requires time, energy and money, or ends up somewhere that it simply cannot be reused for the sake of drinking or nourishing the land. Essentially you are migrating the water to places that are less readily available to humans and/or wildlife or nature.
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