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New Jersey State Police Marine Services Bureau. The steel bulkhead, installed between 1965 and 1972, retains the sides of the canal and protects the embankment. Bulkheads typically have a 50-year life. Sections of a bulkhead exposed to tide cycles are particularly vulnerable to rust and corrosion because of the daily exposure to seawater and oxygen. Inspections dating back to 1983 revealed minor corrosion, and USACE engineers began analyzing and studying methods to address the issue. "Through our test case, we found it was signifcantly cheaper to repair and coat the bulkhead rather than replace it," said the chief of the Philadelphia District operations division. The team studying the matter estimated that repairs could save approximately $25 million over replacement. The hard part, however, was working out the engineering of the project. That kind of work had never been done in the United States, and district engineers hoped that the project would demonstrate to USACE and local private interests that the infrastructure could be rehabilitated at a cost savings. The work to repair the bulkhead involved moving a barge carrying generators, sandblasting equipment, and a desalination station to produce freshwater to wash the steel onsite. The contractor began the process by maneuvering movable cofferdams (temporary watertight enclosures) against the bulkhead and pumping the area dry to expose the length of the steel bulkhead. Crews used a high-pressure wash to remove paint, rust, and marine growth and then checked the thickness of the steel with an ultrasonic thickness gauge. Wherever they found spots corroded by more than half of the Cofferdams allow a close examination of corrosion on the bulkheads. original thickness, workers welded steel plates to the existing structure. After a round of sandblasting, the bulkhead was ready for a special coat of marine paint. Each stretch of bulkhead repair took several days before the contractors moved the cofferdams to other areas. "Our contractor pioneered a number of different features along the way," said a USACE project engineer, who noted that the bulkhead includes three different types of sheet pile, depending on when it was installed. Each type has different interlocking features, requiring the contractor to modify and adjust plans as the work progressed. Two unique aspects of the project included the use of the movable cofferdams and the application of a marine coat that could cure in wet conditions. These features reduced the time and cost of the work. Adapting to conditions on the ground was essential for the contractor. A construction manager for the frm pointed to the engineering challenges presented by the weather, tides, boaters, bridges, and the features of the steel bulkhead itself. A safety inspector with the frm said "[The project is] prestigious, and we're all pretty proud to be involved with the work." The contract work repaired half of the bulkhead along the canal. Philadelphia District offcials hope to repair the entire length of the bulkhead before deterioration requires the full replacement of the uncoated sections. A barge serves as a staging area during bulkhead repairs along the Point Pleasant Canal. May–August 2013 Mr. Rochette is a public affairs specialist with the USACE Philadelphia District. Engineer 27