I-595 Corridor Improvements

The I-595 Corridor Improvements project in South Florida is one of the largest public-private partnerships (P3) in the U.S. The $1.8 billion in improvements to widen and expand the 10.5-mile corridor include the addition of auxiliary lanes, bypass and braided ramps, collector-distributor roadways, and a tolled reversible express lanes system.

Serving as the Owner’s Representative to the Florida Department of Transportation (FDOT), RS&H developed the initial design, supported FDOT throughout the procurement process, and assisted with the ultimate selection of the concessionaire team. We continue to provide project reviews and engineering oversight throughout the design and construction, including working closely with the concessionaire team to identify and implement innovative concepts and address technical solutions.

Our involvement in this project dates back to 2000 when we served as the Corridor Design Consultant. In this role, we oversaw the Master Plan development, prepared the Preliminary Engineering Study for the corridor, and developed the preliminary engineering plans for procurement of the P3 project.

PD&E Study
I-595 (SR 862) is the only east-west corridor in the heavily urbanized Southeast Florida region, linking Fort Lauderdale-Hollywood International Airport, Port Everglades, I-95, Florida’s Turnpike, and I-75. Increasing traffic volumes and congestion required improvements to the corridor that would ensure sufficient capacity to accommodate the region’s continued growth. In 2006, RS&H conducted a Project Development and Environment (PD&E) Study to investigate improvements to east-west travel operations, capacity, and safety along 12 miles of the corridor.

RS&H developed the study in conjunction with several diverse interests in mind, including the surrounding municipalities and counties, local water management district, toll authority, and rail service. The team also considered other current and future projects in the region, as well as ensured nearby pristine wetlands adjacent to the corridor were protected from encroachment by the new or reconstructed corridor features.

The PD&E Study led to the selection of an ultimate system alternative that included a transit component, elevated reversible lanes, braided ramps, and auxiliary lanes, a continuous connection for SR 84, and interchange improvements/upgrades along the corridor. Phasing of the corridor resulted in the development of 15 separate projects ready for design.

Owner’s Representative
RS&H served as the owner’s representative and was responsible for a wide variety of services:

• Development of project costs for financial model
• Preliminary design
• Coordination with legal and financial teams
• Public involvement and outreach
• Risk assessments and evaluations
• Preparation of Request for Qualifications and Request for Proposals
• Development of evaluation criteria and scoring recommendations
• Presentations to scorers based on factual finding of the evaluation of proposals
• Negotiation support for contract execution
• Review of design submittals
• Release for construction plans
• Design and management support throughout construction

Shared-Use Drainage
Limited right-of-way available along the 10.5-mile corridor posed significant permitting and drainage challenges. To minimize right-of-way acquisition and avoid impacts to nearby residents and businesses, RS&H designed shared-use drainage facilities by partnering with three privately owned golf courses adjacent to the corridor: Lago Mar, Pine Island Ridge, and Arrowhead.

RS&H provided quality verification and oversight on the final design and construction of the Lago Mar and Pine Island Ridge Golf Courses and served as the final design consultant for the Arrowhead Golf Course. The drainage facilities within the Arrowhead Golf Course consist of a series of wet detention ponds, which are interconnected with 48-inch pipes. The increased pond areas and modifications to the interconnecting pipes and control structures maintain the peak stages within the golf course ponds and the peak discharges from the ponds into the receiving water bodies at approximately the existing levels.

By incorporating social, economic, and sustainable design considerations, the I-595 shared-use drainage project offered a “soft” engineering solution that effectively balanced transportation needs with the surrounding environment and community. The project ultimately saved FDOT over $60 million in potential right-of-way acquisition costs, offered a solution for implementing capacity improvements in highly populated and dense urban areas, and balanced the state’s transportation needs with social and environmental considerations.

North New River Canal Hydraulic Analysis
While serving as the Corridor Design Consultant for the I-595 Corridor Roadway Improvements in Broward County, Florida, RS&H completed a hydraulic analysis of the North New River Canal (NNRC), which lies within the study corridor right-of-way. The proposed improvements require portions of the canal banks to be filled in behind sheet pile bulkhead. Several bridges that cross the NNRC will be replaced and new crossings added. The Florida Department of Transportation has committed to preserving the flow capacity and maintainability of the canal while making the proposed roadway improvements, therefore analysis was required to ensure the capacity of the canal remained at or above the existing level.

The NNRC Basin has an area of approximately 30 square miles and is bordered by Water Conservation Area (WCA) 2B, Florida’s Turnpike, and I-595. The Canal Hydraulic Analysis assessed the hydraulic conditions associated with the existing and proposed canal geometry, as well as the structures that cross it. Approximately half of the canal within the study area is controlled by a gated control structure, Sewell Lock (G-54), which discharges to the North New River, a tidally influenced stream.

Utilizing detailed topographic survey, along with Microstation and Geopak, RS&H created a detailed set of existing condition cross sections for use in HEC-RAS. The HEC-RAS model extended approximately 9.6 miles upstream of the Sewell Lock and included 14 individual bridge structures and approximately four miles of channel cross-section modification. RS&H then conducted a detailed analysis of impacts to the water surface profiles by creating an updated proposed condition model that incorporated the proposed bridge modifications. Through this analysis and careful coordination with the project team, the team selected and recommended a design that would not impact water surface elevations in the canal.