Conventional sanitary sewer evaluation and survey (SSES) and renewal and replacement (R&R) techniques are steeped in tradition. Unfortunately, these approaches to wet weather management have a long track record that has just as many success stories as failures. We know this to be true because all sewer systems still experience some level of wet weather flow management issues such as inflow and infiltration (I&I) even since the EPA’s introduction of SSES programs in 1975.
For too long, the engineering industry has completed I&I investigation in some fashion, then completed some level of monitoring, then force fit a model after spending millions on renewal and replacement strategies in the hopes of I&I reduction during wet weather. Municipalities are rarely presented quantitative operational goals based on modeling alternatives such as peak flows at the plant that are based on a reduction percentage of I&I, or wet weather storage at a key location that would resolve conveyance issues without upsizing downstream pipes, pump stations, and plants. This has created 11 major pitfalls for managing wet weather concerns.
In this article, McKim & Creed Wet Weather Manager Ken Orie, PE, explains these pitfalls and offers new approaches to better manage I&I removal rates, reduce SSOs and optimize wastewater treatment operations. Click on the image to read the article in its entirety.