| MadSci Network: Engineering |
This is a somewhat common "urban myth". Drinking fountains have a water supply line and a drain line -- just like the faucet and sink in your house. There is no attempt to recycle the water in the fountain. Fountains that supply cooled water do so via cooling coils; basically the fountain contains a miniature refrigerator to cool the water. It would be very costly (and impractical) to have a public fountain that could filter and purify the waste water.
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