The 310-mi.-long St. Johns River flows near the east coast of Florida from west of Vero Beach to just north of Jacksonville. The state's longest river, the St. Johns River, flows northward. The river separates the cities of Green Cove Springs and St. Augustine, which are approximately 30 mi. south of Jacksonville.

FDOT photo

The Florida Department of Transportation (FDOT) and Florida's Turnpike Enterprise are undertaking a long-term project — the creation of the First Coast Expressway (FCE). Upon completion, the $1.9 billion FCE will be a 46-mi.-long 4-lane limited access toll road. It will connect I-10 in Duval County to I-95 in St. Johns County.

The first project began in 2008 with the initial project coming south from I-10 and is scheduled to conclude in 2030. FDOT split the expressway project into eight separate projects. Among the projects is the new Shands River Bridge, which connects Green Cove Springs in Clay County to St. Johns County.

Existing Bridge

The original Shands Bridge was opened in 1928. The wooden toll span draw bridge was replaced in 1963. The existing bridge is two lanes, has minimal shoulder width and no lighting.

Another issue with the current bridge is that the clearance is 45 ft. Clearance on the nearby Buckman Bridge, approximately 15 mi. to the north, and Memorial Bridge 22 mi. to the south, is 65 ft. (vertical). The difference in height limits marine commerce in the area.

FDOT photo

The new bridge will address each of these issues, thereby providing improved connectivity, according to CJ Youmans, associate vice president of RS&H, who is the owner's representative on the First Coast Expressway project.

"The new bridge will be high-speed [70 mph] and will include four travel lanes with wide inside/outside shoulders, lighting and a separated shared-use path to accommodate pedestrian and bicycle traffic," Youmans said.

The bridge also will feature a vertical clearance of 65 ft., allowing for larger vessels to navigate along the St. Johns River.

The overall length of the new bridge will be approximately 9,282 ft., or nearly 1.8 mi., and it will have 72 spans. In addition to travel lanes and inside and outside shoulders, the bridge will have a 12-ft.-8.5-in. shared-use path with overlooks at the center span.

"The driver experience [on the new bridge] will be greatly enhanced with improved safety, higher speeds and less congestion," Youmans said.

Note that FDOT projects the ADT to be 62,200 in 2030 and 80,000 in 2050.

The bridge is part of the third and final segment of the FCE. The segment also features interchanges at CR 16A and SR 16 near Bayard Conservation Area.

"The trip using these interchanges will not be tolled, providing for free access over the St. Johns River," Youmans said.

Soil Issues

The new Shands Bridge will be just south (approximately 90 ft.) of the current bridge. The complete separation of the old and new bridges will allow for some parts of the existing bridge to be maintained; it will be used for recreation and fishing.

FDOT photo

The new bridge, according to Thomas Woods, a senior project engineer of HNTB, the CEI consultant on this segment of the First Coast Expressway, will be a high-level concrete bridge — concrete supports, beams and deck.

"A concrete bridge was chosen for ease of maintenance, functionality, economics and general aesthetics," Woods said.

The team is installing huge concrete cylinder piles (60-in. diameter) to support the bridge at the approach spans, and large numbers of square piles (30 in.) throughout the main spans. They need to drive the piles up to 100 ft. in the soil below the surface of the water, so they provide sufficient support.

Getting to the depth has proven to be a challenge with the mix of geotechnical conditions.

"The river bridge construction is complicated by water depths on the outside edges that do not allow construction from a barge," said Woods. "The contractor has constructed an extensive trestle bridge on both sides of the river to allow construction in shallow water

"The first few challenges have been associated with the geotechnical conditions of the site. Large volumes of subsoil have had to be removed adjacent to the river — almost 300,000 cubic yards — and the contractor is averaging soil import on average 1,000 cubic yards per day to replace the mucky material."

To remove the subsoil, the team has used an excavator equipped with flotation tracks that allow it to "float" on the soft mud and the water as well.

Another geotechnical challenge — dealing with deep clays that require ground improvement strategies.

"We're placing approximately 550 wick drains per day [120,000 total] that will allow a surcharge program to speed consolidation," he said.

The team is installing the wick drains via an excavator with a mounted wick drain stitcher. The stitcher pushes the wick drain to the desired depth, Woods said. The wick drain then permits water to escape the clay soil and consolidate.

Design Build

This project is being delivered through a design-build approach.

FDOT photo

"FDOT determined that the design-build method would provide the department with the best value balancing price and technical merit in the project selection," Youmans said.

The team that won the contract includes WGI Inc., Johnson Bros. Corporation and American Bridge. They were selected to complete the project at nearly $596 million. Youmans said the project is currently on budget.

The design phase of the project began at the end of 2022. The first year and a half focused primarily on design. The original contract time was 2,580 days. However, FDOT added 123 days due to weather issues.

Project completion is expected in May 2030. Woods explained that the date is subject to change based on weather, special events and unforeseen circumstances.

When the new Shands Bridge is complete, drivers will experience a safer ride, while pedestrians and cyclists will enjoy the shared-use path, and taller boats will be able to travel the area. When the entire First Expressway travels through Clay County, it will be faster and smoother. CEG