Frequently Asked Questions

The Project Development and Environment (PD&E) Study considered several alternatives, including low- and mid-level movable bridges and a fixed high-level bridge. These bridge types were analyzed with several horizontal alignment options. Based on the PD&E Study, the preferred alternative is a mid-level movable bridge. This preferred alternative was finalized upon receipt of Location and Design Concept Acceptance (LDCA) by the Federal Highway Administration in March 2019. The new bridge will be a twin double-leaf bascule bridge similar to the existing bridge.

The project is in the detour phase. The US 1 bridge closed to vehicle and pedestrian traffic on March 13, 2023. Traffic is being detoured to Alternate A1A. During this phase, the existing bridge will be demolished. Construction of the replacement bridge will continue with the new bridge anticipated to open to one lane of traffic in each direction by fall 2024.

The replacement bridge’s main channel will have 125 feet of horizontal clearance (existing is 90 feet) and up to 42 feet of vertical clearance (existing is 21 feet). The increase in vertical clearance will reduce the number of bridge openings by 44%.

The preferred construction method for this project entails removing the existing bridge in its entirety and detouring traffic to Alternate A1A.

A significant portion of the new bridge will be constructed during a 20-month detour. Following the 20-month detour, a higher bridge with bicycle and pedestrian facilities will be opened to one lane of traffic in either direction. The remaining portion of the new bridge will be constructed in 15 months following the detour phase. The estimated total construction time of this method is 42 months. This preferred construction method provides the following benefits:

• Avoids delicate removal of half the existing bridge
• Significantly reduces risk of existing bridge settlement and extended unplanned detours
• Delivers new higher bridge with two lanes and 44% less openings within the first phase
• Expedites construction of bicycle and pedestrian facilities
• Improves work zone mobility and safety
• Reduces total construction duration by approximately 18 months

Construction began in October 2021 with completion anticipated in early 2026.

There will be a 20-month full bridge closure and detour to Alternate A1A. Details on the detour route can be found on the main page of this site by clicking the “Traffic Management and Intersection Improvements” tab on the left side of the main page. Prior to the bridge closure, the following intersection improvements will occur along the detour route to improve traffic flow during construction:

• • Alt A1A at Old Dixie Highway (permanent)
• Shifting the intersection to the southwest
• Adding a traffic signal
• Lengthening the left-turn lane from northbound Alt A1A to northbound Old Dixie Highway
• • US 1 at SR 706/Indiantown Road (temporary)
• Three left-turn lanes from northbound US 1 to westbound SR 706 (two left-turn lanes currently)
• •SR 706/Indiantown Road at Alt A1A (temporary)
• Two left-turn lanes from southbound Alt A1A to eastbound SR 706 (single left-turn lane currently)
• Two right-turn lanes from westbound SR 706 to northbound Alt A1A
• Alt A1A at US 1 (temporary)
• Two right-turn lanes from southbound US 1 to westbound Alt A1A

Intelligent Transportation System (ITS) devices will be placed along the detour route to allow 24/7 monitoring and active traffic management by the Florida Department of Transportation and Palm Beach County. These enhancements will improve travel times, alleviate congestion, allow real-time adjustments of traffic signal timing and allow advance notification to the public of traffic delays.

Marine traffic will be maintained at all times. Channel restrictions may occur. The Intracoastal Waterway bridge will continue to open on demand.

The estimated timeframe of the 20-month detour phase is from spring 2023 to the fall 2024. Refer to the estimated construction schedule on the main page of this website.
The Florida Department of Transportation has provided incentives / disincentives to the contractor to limit the detour’s duration. The contractor may receive up to $3.5 million if the detour ends in less than 20 months and one lane of traffic in each direction is open on the new bridge. The contractor faces a $35,000 per day penalty if the detour extends past 20 months.
The contractor may earn additional “no excuse” bonuses that includes $1.5 million to open two lanes of traffic in each direction by November 2024 and $1 million to complete the project within 1,458 days.

The estimated construction cost is $122 million.

Landscaping will be planted along the project corridor following the completion of the bridge replacement project.

The observation deck will be closed during construction. The observation deck will be demolished and a replacement observation deck will be built under the new bridge.

The replacement bridge will have a wider section to accommodate sidewalks and bike lanes in each direction. The number of vehicular lanes will remain the same. The replacement bridge also will have a higher vertical profile.