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.)
For students in Canada: Due to the ongoing Canada Post strike, please use UPS or FedEx to return your scantrons for grading. You may take your exams online even if you received paper exams.
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 R
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
rising sludge
Rising sludge occurs in the secondary clarifiers of activated sludge systems when the sludge settles to the bottom of the clarifier, is compacted, and then starts to rise to the surface, usually as a result of denitrification, or anaerobic biological activity that produces carbon dioxide or methane.