Canal board asks staff to re-evaluate seawall materials after Taylor study; local supplier pitches noncorrosive rebar

The Punta Gorda Isles Canal Advisory Committee on Sept. 15 asked city staff to update the 2021 Taylor engineering study and provide revised cost and life-expectancy estimates for alternative seawall materials, including stainless-steel reinforcement, fiberglass-reinforced polymer (GFRP) rebar and vinyl panels.

The request came during a detailed presentation by Mark Storm, canal maintenance supervisor in the city public works department, who summarized the original Taylor study and the city’s current seawall program. “The canal maintenance program included designs, materials, manufacturing process, construction methods, maintenance, and inspection records,” Storm said. The study covered about 110 miles of seawall in the city; staff told the committee the Taylor work (completed in 2021) needs targeted updates to reflect new materials and current pricing.

Why it matters: Punta Gorda’s seawall replacement program is a multi-year, multi-site effort funded partly by property assessments and affected by FEMA reimbursements, and material choices affect longevity, staging logistics and overall cost. Committee members repeatedly urged staff to balance the cost of any new study with pragmatic, targeted updates that will inform imminent procurement decisions.

What staff recommended and what the board asked for Staff recommended reevaluating: (a) the city’s current concrete panel mix (including possible stainless-steel reinforcement), (b) GFRP (fiberglass) rebar options, (c) alternative panel materials such as vinyl or fiber-based panels, and (d) life expectancy and replacement timing for tieback anchors (often called manta-ray or MR1 anchors).

Storm told the board he favored limiting the update to a narrow set of options — the current design plus up to two alternatives — rather than a full, repeat of the original 600-page Taylor study. “Materials change all the time,” Storm said. The board asked staff to return with updated costing, expected service life, and notes on constructability and staging for the top alternatives.

Supplier presentation on GFRP Local supplier Richard Kipper addressed the committee and urged approval of GFRP as a direct replacement for the steel (Chromex/MMFX) reinforcement currently used in panels and caps. Kipper said the material is “a 100% non corrosive solution” and argued it can reduce weight and long-term corrosion risk. He supplied a vendor cost comparison tied to a 2024 bid package, saying the Chromex bar in that solicitation was about $57,000 for the order while his GFRP quote for equivalent pieces was $20,794. Kipper also said the product is already in use on Florida Department of Transportation projects and on local projects such as the Sanibel Causeway.

Public works staff noted technical caveats. Brian Clemens, public works, and Storm explained that FRP rebar is encapsulated in concrete and that vibration during casting can sometimes allow lighter rebars to shift; they recommended any update include constructability testing and specification changes to address that risk. Storm also asked the board whether the city should re-evaluate the life expectancy of common tiebacks (MR1/manta-ray anchored plates) so anchors and panels age together.

Project status and logistics Staff reported on ongoing seawall replacement work: pay applications are moving through (one pay application was approved the morning of the meeting), two sites in the Mangrove area were complete, and the larger panel replacement program is progressing by zones. Committee members asked about the number of barges used for repair work; staff said four barges are dedicated to reef/repair work with one additional barge for routine maintenance and that the contractor’s schedule targets substantially increased installation through the coming spring, subject to weather and hurricane damage.

Permitting and mangrove trimming Jake Dye raised questions about state and federal authority over mangrove trimming and removal near seawalls. He noted that state statute can allow mangrove removal where it interferes with docks in seawalled, man-made canals but that federal agencies — the National Marine Fisheries Service and the U.S. Army Corps of Engineers — may require joint federal permits. Brian Clemens said seawall replacement permits include limited allowances for trimming and that removal may require mitigation credits; staff said they would review specific statutes and federal permit language and follow up.

Board direction After public comment and supplier testimony, the committee provided a consensus to have staff update the Taylor analysis to (1) evaluate the city’s current concrete mix and stainless option; (2) evaluate GFRP rebar and up to two alternative panel materials (for example vinyl or fiber panels); (3) review tieback life expectancy and compatibility; and (4) report revised unit costs, life-expectancies and constructability concerns back to the committee. Mark Storm summarized the request: “We’re just kinda looking for a consensus whether we want to revisit this topic.”

Public comment Richard Kipper, representing a local supply business, urged the city to adopt GFRP and provided the vendor cost comparison cited above. Community member Debbie Lux offered an independent perspective in public comment, urging the committee to consider rapidly changing composite technologies and the broader lifecycle costs.

Next steps Staff said it would provide the committee with the Taylor study and a targeted update comparing the top alternatives at the next meeting; the committee asked staff to avoid analysis paralysis and to focus on actionable cost/life information that can be used in upcoming procurement steps.