Problem During rainy periods in Nederland, Texas, storm water inflow and infiltration (I&I) was seriously impacting manholes up- stream and downstream of a 30-inch sanitary main trunk line. Soil was eroding into the line, and large voids were forming in proximity to the manholes. The situation became critical when the city treatment plant became overloaded with excess water. Facing water treatment cost overruns as well as potential failure of an increasingly compromised sewer system, city officials were looking for answers. Analysis A video of the line revealed that the I&I was occurring at the manholes. City officials originally considered a cured-in-place liner for the repair but digging up the line was not feasible due to the complexity of parallel and cross pipelines above and bel

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