The 48-Inch Water Transmission Main Design and Construction Project exemplifies David Mancini & Sons, Inc. (DMSI)’s multidisciplinary expertise in large-diameter pipeline design, microtunneling, and full-service utility coordination for complex regional infrastructure.

The project encompasses the design and construction of approximately 6.0 miles (15,308 linear feet) of 48-inch diameter prestressed concrete cylinder pipe (PCCP) forming a critical segment of Miami-Dade Water and Sewer Department’s (MD-WASD) transmission network. Along the route, approximately 712 linear feet of microtunneling was required to install a 48-inch carrier pipe inside a 72-inch steel casing beneath SR-874 and the CSX Railroad, ensuring uninterrupted traffic and railway operations.

DMSI’s innovative alternate route proposal to MD-WASD optimized the project’s alignment — reducing construction duration, minimizing community disruption, and lowering overall costs while maintaining full compliance with agency standards.

In addition to the 48-inch main, DMSI installed a 16-inch ductile iron force main along SW 127th Avenue (from SW 108th Street to SW 88th Street/Kendall Drive) to replace existing 16-inch and 12-inch asbestos cement (AC) pipelines. Following successful installation and testing, all existing AC mains were safely abandoned.

The project’s scope also included surveying, geotechnical analysis, utility conflict identification, MOT planning, resurfacing, SP&M coordination, QA/QC oversight, shop drawing reviews, RFI responses, and full as-built certification and close-out documentation.