Prysmian Du Quoin Plant

Since 2023, G&W has engineered two rounds of expansion at this Du Quoin, Illinois manufacturing plant, working through a general contractor, two architects, and directly for the owner.

The work began with front-end studies for a general contractor. The first used calculations in coordination with the manufacturer to select process cooling towers. The second reviewed utility bills, peak demand, and the existing one-line to test whether the plant’s electrical service could carry the planned growth. The first expansion added 119,300 SF to the existing 226,000 SF plant across expanded production lines, a two-level office area, an enlarged parking lot, and storage. G&W started on design-build bridging documents for the architect, and the project converted to fully engineered MEPFP construction documents with G&W as engineer of record. To keep the schedule moving, three pieces were released early as accelerated packages: the cooling towers, including decommissioning an existing pond; a new quality lab; and final switchgear selection. Utility coordination, site photometrics, a fire protection performance specification, final construction drawings, and phased construction administration followed.

A second architect and general contractor brought G&W back for four more building additions totaling 65,500 SF, led by a 44,200 SF production addition. MEPFP Engineering tied each addition into existing plant systems. Further, G&W’s civil team is designing a new truck route: 60,000 SF of new road, a widened existing road, a turnaround, a 250 LF retaining wall, and an at-grade railroad crossing, with documents to be submitted to the City of Du Quoin and IDOT. At the new entry into the site, a 400 SF guard building and weigh station serve two semi-truck scales.

Alongside the project work, the owner retains G&W directly for ongoing MEP consulting at the plant.