Coastal Resilience
Isle of Palms moved dredged sand straight to the intertidal beach
City of Isle of Palms; Ahtna beneficial-use placement, 25 February 2025
USACE linked two different maintenance jobs to one Isle of Palms receiving area. Ahtna rehandled stored AIWW material, while Cottrell dredged active shoals and used both open-water and beach-placement routes. About 700,000 cubic yards were placed below high tide between 2nd and 10th Avenue.
What changed
The USACE project page sets the original allocation, below-high-tide rationale and 26 January 2025 contract requirement. Its April 2025 fact sheet records the March 2024 award and active placement. City updates define Cottrell's material routes, Ahtna's January 2026 remaining quantity and the two contractors' work-area coordination. USACE controls the combined completion status and approximate 700,000-cubic-yard total; the City separately records Cottrell's 265,000 cubic yards, both contractors' 27 February completion, the April clay cleanup and 12 May staging clearance. A final Ahtna quantity, package-value estimate and attribution of schedule responsibility are not published. The aerial photograph shows Ahtna placement in progress on 25 February 2025, not the final 2026 beach condition.
Why it matters
The March 2024 maintenance contract originally allocated about 500,000 cubic yards to Isle of Palms and 200,000 to Sullivan's Island. Cottrell's later package added active-shoal dredging, with Dewees Inlet and shoal 1B material routed offshore before shoal 1A material went to the beach. One receiving shoreline served two separate maintenance packages, but their quantities, material routes and commercial boundaries stayed distinct.
Decision read
What remains open
Below-high-tide placement was chosen partly to save cost and let tides wash silt, clay and vegetation out of the sand. It did not remove every material risk. Concentrated clay pockets formed on the shoreline and needed a six-day low-tide cleanup in April. The original rehandling contract required completion by 26 January 2025, while both beach-placement campaigns actually finished on 27 February 2026. Public records do not assign responsibility for the longer period. The remaining questions are what changed in the sequence, what surveys show about the channel and beach, and whether recovered placement-area capacity lasts through the next maintenance cycle.
Next watchpoints
- Post-dredge condition at the AIWW and Breach Inlet shoals
- Measured beach-profile response between 2nd and 10th Avenue
- Further clay exposure or cleanup after tidal sorting
- Recovered capacity in the four source placement areas
- The interval before the next maintenance campaign
Sources used 7
- Dredging projects finish, boosting Isle of Palms coast with no local costs U.S. Army Corps of Engineers, Charleston District, 20 April 2026
- Completed beach projects City of Isle of Palms, Project updates through 12 May 2026
- Charleston District transforms dredged sand into coastal resilience U.S. Army Corps of Engineers, Charleston District via DVIDS, 28 April 2026
- FY24 Beneficial Use Sediment Rehandling at Breach Inlet U.S. Army Corps of Engineers, Charleston District, Current project page accessed 18 July 2026
- Atlantic Intracoastal Waterway, SC project fact sheet U.S. Army Corps of Engineers, Charleston District, 11 April 2025
- Update on USACE Beneficial Use Project: Sediment Rehandling at Breach Inlet City of Isle of Palms, 23 January 2026
- Update on USACE Beneficial Use Project: Dredging Intracoastal Waterway City of Isle of Palms, 16 December 2025
Corrections and methodology
Facts are dated to the source record above. IMWO updates the brief when procurement, award, delivery, or scope evidence materially changes.
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