noun
water purification plant; water filtration plant
A facility where raw water is treated to make it safe for drinking or other uses.
この町の浄水場は一日に十万トンの水を処理できる。
This town's water purification plant can treat 100,000 tons of water per day.
浄水場の見学
I went on a tour of the water purification plant and learned how water is cleaned.
下水処理場 is a sewage treatment plant for wastewater, whereas 浄水場 treats raw water to make it potable.
Compound of 浄水 (purified water) + 場 (place). The term straightforwardly describes a facility for water purification.