Redi-Rock Wall Reinforces Green Cove Springs Riverfront

THE CHALLENGE

Faced with a rapidly eroding 12 ft (3.6 m) bluff at the end of a dead-end street in Green Cove Springs, city officials and their engineering team identified Redi-Rock as the right solution for river stabilization and shoreline protection along the St. John’s River.

The project site required a retaining wall system to support maintenance access, manage stormwater, and withstand North Florida’s unpredictable weather conditions, including floodwater and hurricane-force storms. To meet permitting requirements and Florida building codes, additional structural engineering was needed. Truemont Materials stepped in, bringing in a trusted engineering partner to get the job done right. It was a true collaboration, with the city leading the vision and Truemont supporting with the expertise and tools to make it a reality.

THE SOLUTION

To help the City of Green Cove Springs meet its long-term resiliency goals, the project’s engineers made a strategic choice: a Redi-Rock gravity retaining wall system. Knowing the site demanded more than basic structural support, they prioritized a retaining wall solution built to endure storm surge, hurricane-force winds, and ongoing tidal fluctuations.

Sheet pile walls were initially considered but quickly ruled out due to their rigidity and inability to allow water to flow through the structure. Another deciding factor was the ability to incorporate a cast-in-place collar for stormwater into the wall, an option easily integrated into the final design. Once city officials saw that Redi-Rock offered similar upfront costs with far greater long-term durability, the decision was clear.

The completed Redi-Rock wall delivers:

• Stormwater Management Redi-Rock systems are designed to manage water more effectively than sheet pile walls. Their dry-stacked joints allow stormwater to pass horizontally and vertically, with each seam functioning as a built-in relief joint to reduce hydrostatic pressure. To further enhance drainage, especially in the event of a rapid floodwater drawdown, a 1:1 wedge of stone was placed behind the wall. A stormwater pipe and outfall were integrated directly into the wall to support targeted water management. These features make Redi-Rock an ideal solution for sites with variable water flow.

• Wave and Erosion Control A layer of riprap placed in front of the wall serves multiple purposes: it absorbs wave energy, prevents scour, and helps retain soil at the base. By catching sediment, the riprap adds an extra layer of erosion protection. It also supports a living shoreline environment by encouraging vegetative growth and providing habitat for wildlife, enhancing both the stability and ecological value of the Redi-Rock installation.

• Engineered Drainage Behind the wall is a 1:1 stone wedge that promotes substantial drainage. Additional drainage materials, fabric, and #57 stone, placed beneath the wall, work together to relieve hydrostatic pressure.

• Resilient to Water Level Changes The Redi-Rock gravity system is built to prevent erosion and handle water fluctuations, protecting infrastructure from long-term flood damage. The completed wall withstands rapid drawdown as stormwater recedes, critical for overall wall performance in hurricane - and flood-prone environments.

• Expedited Installation In approximately one week, contractor DB Civil installed a 989 sq ft (91.8 sq m) wall featuring a cast-in-place collar and integrated pipe for stormwater. As the contractor’s first Redi-Rock installation, the modular Redi-Rock concrete blocks, made of reinforced concrete, helped streamline the installation without compromising performance. A traditional steel bulkhead design would have taken weeks to install and delayed project progress.

• Lifetime Performance with Aesthetics While aesthetics weren’t the primary concern, the system offers a natural, consistent finish. More importantly, it delivers the longevity and resilience the city requires to protect its infrastructure for the long haul, and is already being considered for seven more riverfront projects.

• Approved for Use Truemont Material’s Redi-Rock solutions are Florida Department of Transportation (FDOT) approved for incidental products, making them a trusted choice for public projects across Florida.

“The faster we could get in and out of the river, the better. Once the base was in place, the wall itself went up in just one week. Installing traditional steel sheet pile would’ve taken weeks and caused far more disruption.”

Mike Null, Assistant City Manager, City of Green Cove Springs

THE PROJECT

A permit from the City's building department was required for any bulkhead or retaining wall project in Green Cove Springs. This added a layer of complexity for the city team, particularly regarding the structural documentation needed to meet state building codes for wall structures in coastal and flood-prone zones. The scope of the requirements extended beyond the expertise of the city’s civil engineer.

That’s where Truemont Materials stepped in. To help navigate the permitting process, Truemont coordinated with a trusted structural engineering partner. They delivered the supplemental drawings and technical support needed to satisfy all code requirements, keeping the project on track and compliant. By stepping up at a critical moment, Truemont ensured the city had the confidence to move forward.

With the gravity wall approved, installation took just one week to complete.

THE OUTCOME

Faced with the urgent need to protect critical infrastructure and municipal streetscapes from severe weather events, the engineers leading this project made a pivotal choice: Redi-Rock. Aesthetics didn’t drive their decision, but performance, durability, and long-term impact. This installation became a key part of the City of Green Cove Springs’ broader resiliency initiative to protect municipal assets from future storms. Additionally, the natural stone-like aesthetic of the completed Ledgestone wall convinced nearby homeowners that the city made the right decision to bring on Redi-Rock.

Encouraged by this project’s success, the city plans to use Redi-Rock as the standard across its resiliency program, with seven more retaining walls of similar design already in the works.

Products Featured

28 in (710 mm) Top Block 28 in (710 mm) Middle Block 41 in (1030 mm) Middle Block 52 in (1320 mm) XL Block 72 in (1830 mm) XL Block