Warfield Relief Sewer

The City completed flow monitoring and XPSWMM model development of the Interceptor to determine the relief sewer sizing and connection point locations. However, it was determined early on in the design process that the modeled route was not constructible. Therefore, American Structurepoint was tasked with making significant routing design revisions while still providing the necessary relief points (cross connections). This required significant coordination with the Owner and its modeling staff. In addition, the design included several innovative components such as multiple conflict and diversion structures and two triple-barrel siphon structures to transmit relief flow under an existing creek. The design also included significant site regrading, deep sewer construction, and installation of approximately 300 lft of 48-inch steel casing under US 27. The estimated cost of the improvements, completed in fall of 2011, was $1.8 million.