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.
(All times are PST.)

If exams are submitted:	Course certificates will be mailed:
By December 13th	By December 20th
After December 20th	Early January

Please note: Postmark dates will not be honored.

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

hydraulic gradient

The slope of the hydraulic grade line. This is the slope of the water surface in an open channel, the slope of the water surface of the groundwater table, or the slope of the water pressure for pipes under pressure.