OWP will be closed from 4:00 pm on Friday, December 20, 2024, until 8:00 am on Thursday, January 2, 2025, for Winter Break.
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Water and Wastewater Terms Beginning H

A B C D E F G H I J K L M N O P Q R S T U V W Y Z

HTH (high test hypochlorite)

Calcium hypochlorite or Ca(OCl)₂.