State Pier Offshore Wind Port Infrastructure Improvements New London, Connecticut

Presentation Description: A case study of geotechnical engineering lessons learned during the construction phase of Connecticut's first offshore wind port development. The $235 million project involves the redevelopment of the State Pier facility in New London, CT. The intent of the project is to provide a purpose-built facility for heavy cargo staging and deployment, specifically offshore wind components. The existing bulkheads and marine structures are being replaced and the area between the solid filled State Pier and Central Vermont Railroad Pier, known as “Central Wharf”, is being filled to provide additional staging area at the port. Filling Central Wharf will require about 400,000 cubic yards of material to be placed though about 40 feet of water ( the tidally influenced Thames River ) and then compacted. Originally, the design involved soil-mixing and ground improvement with stone columns. GZA’s innovative method involves a staged approach to filling where the first stage of filling is intended to penetrate and stabilize the soft organic sediment. The second stage is mass filling completed by end-dumping and pushing material from land into the Central Wharf, which is a more efficient way to place this volume of material. GZA designed alternatives to the stone column method of compaction which provided significant cost savings to the project. The project is scheduled for completion in October 2022. A virtual construction project tour of the facility can be provided in this presentation..