Prince Street Siphon Design

Randolph, Vermont

DuBois & King provided design and construction phase services for an emergency replacement of a double-barrel sewer siphon in Randolph, Vermont. The original siphon was destroyed by Tropical Storm Irene when the Third Branch of the White River migrated 90 ft to the northeast. D&K engineers assisted the Town with damage assessments immediately following the storm, including identifying and coordinating the installation of an emergency bypass pumping system to eliminate the discharge of raw wastewater into the river from approximately two-thirds of the Town.

Fast-track design included topographic survey of the new river alignment; design of a 300-ft-long, double-barrel, 8-inch diameter HDPE siphon installed using horizontal directional drilling; new siphon inlet and outlet structures; replacement/rerouting of 250 ft of gravity sewer and manholes on the north bank; and preparation of easement drawings and coordination with the Town’s attorney. Assisted the Town with an abbreviated contractor procurement process that was acceptable to FEMA, and provided administrative assistance during construction, periodic inspection, and preparation of record drawings. The project received an Engineering Excellence Grand Award from the American Council of Engineering Companies Vermont Section.