How do they clean the plastics and detergents out of our tap water?

Hand dishwashing liquid contains a lot of polymers and other petroleum derivatives. And people actually think it's safe to drink our tap water (USA)?

Update:

solid, no one thinks bottled water is safer, but it sure as cahones tastes a lot better.

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  • 1 decade ago
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    Wastewater is not directly recycled into the tap. It goes through a series of treatments before it is released back into nature, and from there it is further purified through the water cycle. Here's a brief idea of what happens to water after it goes down the drain:

    At the treatment plant (takes several days):

    - screened for solid objects

    - flocculant added and separated by density (the heavier and lighter particles are skimmed off the top and bottom)

    - biological organisms are used to digest impurities

    - more density separation

    - sand filtration (sometimes even reverse osmosis)

    - disinfection (chlorine, ozone, or UV)

    - released into ocean, or river, and then ...

    Water cycle (can take decades, particularly the last steps):

    - flows into the ocean

    - evaporates

    - condenses into clouds

    - precipitates in the mountains

    - seeps into groundwater

    - very slowly filters naturally through layers of rock and sand

    - fills aquifer

    Finally, we tap into the aquifer (groundwater), further purify it and test it again, and then send it to your tap. If you think bottled water is safer, it basically originates from the same place (groundwater) in nearly all cases. Some bottled water even starts out as tap water.

    There are some wastewater treatment programs that accelerate the process by releasing the treated water directly into the watershed, which then feeds the aquifer. The water still gets naturally filtered through the rock; they just skip the evaporation/condensation parts of the water cycle. To justify this, they do extra thorough treatment steps like reverse osmosis, which is the same that many bottled water producers use. These programs are sometimes (incorrectly and misleadingly) referred to as "toilet to tap".

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