Sewer Grouting & Relining Project Overview

Courtesy of Brunswick News {click here for full article}

The City of Brunswick recently completed a major sewer grouting and relining project to help decrease the amount of inflow and infiltration (I&I) entering the sewer system.  Inflow is storm water that enters the system through rain gutters, sump pumps, and foundation drains illegally connected to the sewer system; while infiltration occurs when groundwater seeps into sewer pipes through cracks and leaking or deteriorated manholes.  I&I places a burden on the sewer collection system and waste water treatment plant (WWTP).  I&I may result in the discharge of untreated waste water, higher treatment costs, treatment capacity loss, sewer overflows, and sewer pipe failures.

To address these issues in Brunswick, the City contracted with Standard Pipe Services to complete 11,000 linear feet of sewer main relining, 34,000 linear feet of sewer main line grouting, grouting of 75 lateral connections, and installation of 75 sewer clean outs.  This work totaled $2.2 million, which was funded through bonds issued by the City.

As of direct result of this project, the City was able to reduce peak flows at the WWTP during heavy rain events by 80%, decrease ground water from entering the sewer system by 25%, and reduce the total daily infiltration from entering the sewer collection system by 65%.  This work combined represents an estimated annual savings of $283,000.

Everyone is aware that maintenance, staffing, chemicals, and equipment costs continue to increase.  While this project does not mean the City can decrease sewer rates, it does have an effect on the speed with which rates could need to be increased to help offset rising operational and chemical costs.

The City plans to continue work on improving the waste water system, including identifying and correcting illegal private gutters and floor drain connections.  The City is exploring ways to partner with homeowners with illegal connections to correct these issues.