Green Harbor in Marshfield is situated in the northwestern end of Cape Cod Bay, about 30 miles southeast of Boston and nine miles north of Plymouth Harbor. It is located at the mouth of Green Harbor River, a small stream that drains nearby marshlands. Green Harbor is a popular recreational boating and sport fishing center.

The project consists of:

• A channel extending 4,000 feet from deep water to a six-footdeep turning basin located below the Route 139 Bridge. The channel is six feet deep (eight feet from deep water to the jetties) and 100 feet wide.
• An anchorage six feet deep and five acres in area adjacent to the Town Pier.
• Rehabilitation of the existing state-built west jetty at the harbor entrance. This work included raising the jetty and extending it by 200 feet.
• Raising the existing state-built east jetty.

Green Harbor was completed in October 1969 as a small project under Section 107 of the Continuing Authorities Program.