City staff has worked with our consultant, Consor, to complete a project package for manhole rehabilitation work. The overall focus of this project is to reduce the amount of groundwater and riverwater that enters the wastewater system through manholes. This is known as reducing the inflow/infiltration (I/I) of groundwater into manholes located where there is river influence contributing to groundwater getting inside the manholes.
The extra water in the wastewater system impacts the overall effectiveness of the wastewater treatment & resource recovery facility (WWTRRF). The WWTRRF provides biological treatment of sanitary sewer collection flows, and when groundwater is mixed with sanitary sewer flow, it has to be pumped out and impacts the overall biological treatment.
This project provides for measures to seal the contact points between the manhole base and the first, and in some cases the second barrel rings. Imagine sections of 4-foot diameter pipe, turned on its side and stacked on top each other. The contact points where the pipes are stacked will be sealed from this project work to keep groundwater from entering. The project will focus on 98 manholes located to the west of Main Street ending near McKennon Road.
Estimated completion: 2025
FISCAL IMPACT: Project costs will be expended from the Sewer Fund and is budgeted under capital outlay.
500 SW Dorion Ave
Pendleton, OR 97801
United States
Project Milestones
City Council approved a contract of $110,186 to Cascade Industrial Services, Rathdrum, ID for the Manhole Rehabilitation Project.
Work begins