Americas marine construction intelligence

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Barkley: The Repair Window Runs Through Loaded Testing

Barkley's 2026 dewatering programme put miter-gate and valve repairs inside a planned 52-day navigation outage. USACE's 15 September account described a sequence extending from underwater clearance and chamber isolation through repairs, refilling and tests of miter-gate cycling and valve operation under hydraulic pressure. The work targeted miter gates and filling and emptying valves. Its September programme aimed to restore navigation on 1 October. A separate 2 October navigation notice identified Barkley as the diversion route for Kentucky Lock's planned 13-20 October closure. [1][2]

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Chickamauga: The $19 Million Adjustment After Termination

Chickamauga's lock-chamber termination changed Shimmick's reported revenue while the company contested the decision. The company disclosed a $19 million reduction in both revenue and cost of revenue in its results for the quarter ended 3 April 2026. Its subsequent-events note attributes the adjustment to the 8 May termination notice and previously estimated contract revenue. Shimmick disputes the termination and reported project claims still in process. [1]

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Poplar Island: Grading for the Marsh That Develops After Placement

At Poplar Island, the grading level helps determine how a constructed marsh develops after planting. A 2024 field study compared two areas of Cell 5AB with initial platform elevations of 0.22 m and 0.32 m NAVD88. Three surface elevation tables monitored each area. Mean elevation gains were 13.2 and 7.8 mm/year respectively over the study record through 2021. The lower area gained height faster; the higher area began with 0.10 m more elevation above the same datum. [1]

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Duke Marine Lab: Quantifying a Living Shoreline's Elevation Deficit

Duke Marine Lab's living shoreline has retained its granite sill while the water around it has risen. NOAA's site report records consistent sill elevations between the post-construction survey and a 2025 resurvey. Its 2004-24 monitoring summary puts lower-marsh elevation gain at 2.0 mm/year and mid-marsh gain at 0.3 mm/year, against a local mean sea-level rise of 4.5 mm/year [1]. Those measurements describe different maintenance demands within one functioning coastal asset.

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West Point links gate maintenance to reservoir drawdown and dam-road closure

USACE's 2026 plan for maintenance and painting of West Point Dam spillway gates 1 and 2 combines reservoir drawdown with closure of Resource Management Drive across the dam. The 14 September notice scheduled work and road closure from 21 September, with maintenance expected to finish in mid-January 2027. Its reservoir target was 625 ft by 1 October; the notice leaves the elevation datum unspecified. The dam's technical sheet uses NGVD29. [1][2]

Gulfport's deepening plan includes a later sponsor payment

Gulfport's recommended navigation improvements carry two different sponsor payments. The signed 23 June 2026 Chief's Report assigns $137.102 million of the $548.216 million initial project cost to the Mississippi State Port Authority. It also estimates an additional General Navigation Features payment at $50.8 million, before eligible credits. Paragraph 9(d) places that additional payment after construction, with interest, over a period of up to 30 years. A sponsor's funding forecast therefore needs a construction contribution and a separate post-completion repayment schedule. Annual federal operation, maintenance, repair, replacement and rehabilitation (OMRR&R) is estimated at $17 million, including anticipated maintenance dredging. [1]