I/I rehabilitation has been expanded to include private sector sources
The city of Wheaton, Ill., and the Wheaton Sanitary District jointly developed a master plan, in which the city agreed to reduce excess flows in Basin 4 by 40% and in Basin 3 by 60%. RJN Group Inc. originally began working on the Basin 4 Sanitary Sewer System Rehabilitation Program in February of 2011. In May of 2012, the contract for the rehabilitation program was extended for another year to July 2013 and was expanded to cover City Sewer Basin 3.
The city has performed extensive public sector rehabilitation, yet unacceptable levels of Inflow/Infiltration (I/I) remain. I/I in the sanitary sewer system results in basement backups and sanitary sewer overflows (SSOs) after even small rain events. Since extensive work has already been done in the public sector, the city must now address the private sector sources.
In Basin 4, RJN had previously completed smoke testing and a small amount of building inspection. RJN will now be performing additional services in a portion of Basin 4 designated as a pilot area. In the pilot area, all 600 properties will undergo building inspections by RJN field technicians. In addition, televising will be done on all service laterals from the sewer main. The 40% flow reduction target in the master plan will be accomplished in the pilot area through a combination of removal of any remaining public sector sources, removal of private sector sump pump sources and lining of service laterals. Long term flow metering and utilizing city meters will be used to assess the flows before and after the rehabilitation work.
Services that RJN will perform in Basin 3 include data analysis on city-owned meters and rain gauges, smoke testing on a total of 65,000 linear ft, assessment of manhole condition and creation of a complete basin hydraulic model. Based on this work RJN will provide recommendations for removal of excess flow from the Basin.