Microtunneling under I-75 to Expand Sewer System Capacity in Venice, Florida

To expand capacity and provide redundancy to their sewer collection system, the City of Venice, Florida, completed the Second Force Main Under I-75 project to add a parallel force main beneath Interstate 75 (I-75), with tie-ins to existing infrastructure and a provision for a future connection. At the crossing location, I-75 is a limited-access, heavily traveled, divided highway over 1,000 ft wide from west to east boundaries. Design phase permitting efforts secured approval for a design alternative to Florida Department of Transportation (FDOT) requirements to allow for trenchless construction below the pavement with open-cut construction in the median as opposed to a single, full-length trenchless installation. Project construction was completed in June 2024. This paper summarizes the design and permitting efforts for crossing I-75, the drivers and decisions for the installation method and vertical alignment, explains the contractor pre-qualification and selection process, and provides an overview of construction, including lessons learned and guidance for future designs.