US 41 Design-Build from SR 951 to Greenway Road

WGI was the engineer of record for this project which reconstructed 3.5 miles of US 41 from a two-lane rural roadway to a six-lane divided suburban typical section. WGI incorporated a number of innovations into the design of this project resulting in both a $7.7M savings to the state and a superior design. First, the presence of near-surface limestone and an unusually high ground water table created a challenge to both drainage and permitting. The original concept envisioned a deep drainage system (exfiltration) that would be difficult to excavate and would risk penetration of the Upper Floridan Aquifer. Our team eliminated the deep exfiltration system and proposed dry treatment swales, reducing this burden, as well as saving an estimated $3M for the Florida Department of Transportation. Second, since no off-site ponds were available, the Team designed the stormwater conveyance system to fit within the existing right-of-way, thereby saving the time and money associated with the acquisition process.

In addition, the project required relocation of 14 utilities to a joint use trench which presented complex coordination issues with depth, placement and timing of the relocations. Construction scheduling was intricately coordinated with FPL to eliminate de‐energization occurrences and power interruptions to the local residents. The Team also offered a Cost Savings Initiative Proposal to eliminate the gravity wall at the right-of-way, offering a redesigned noise wall foundation from 36” to 30” to take advantage of the hard limestone soil support. This reduced the cost and construction time needed for installation and saved the FDOT an additional $300,000. The specially designed bottom panels were used to retain fill on the roadway side and, in turn, improved aesthetics on the residential side of the wall.

The project crossed critical Florida Panther habitat; therefore, bridge replacement at Henderson Creek incorporated a panther crossing shelf below the superstructure. To save additional dollars, the Team used recycled 24” pile cut offs for the wildlife shelf reducing the number of piles needed and the foundation footprint. And, finally, the project was completed 150 days earlier than bid, which provided for an additional cost savings.