Presentation Abstract

The Parkersburg Utility Board (PUB) completed a Sanitary Sewer System Evaluation Survey (SSES) and sewer rehabilitation (rehab) project in a selected sanitary sewer system ‘pilot’ area to help quantify the amount of Infiltration/Inflow (I/I) that can be cost-effectively removed. The pilot area selected was in an older section of the system and was identified by flow metering as having a high wet-weather peak-to-average flow ratio. The success of removing I/I from this pilot area will be used to help develop a system-wide approach to SSES/rehab and to fine-tune total system design flows. The results will be presented and an approach identified for addressing I/I in the PUB sewer system.

It was estimated in the SSES that approximately 540 gpm of I/I would be eliminated by rehabilitation of all cost-effective defects in the public right-of-way and on private property, or about 20 percent of the total estimated I/I for the ‘pilot’ area. These values are based on a projected overall I/I removal rate effectiveness of 33 percent assumed for this study. Pre- and post-rehab flow monitoring results will be correlated with rain events. This analysis will contrast actual I/I removal in the ‘pilot’ area with the SSES predictions. Knowledge gained from the ‘pilot’ will be used to develop a system-wide approach to SSES/rehab and to predict successful I/I removal in other parts of the sewer system.