The Neoponset River is located just below South Boston off Dorchester Bay behind Columbia Point. Though not particularly a specific yachting destination for many boaters, the area is well protected and the approach is deep and wide. South Boston is known for its residents (known as Southies who have a rough and tumble attitude, but are generally good-spirited folk.
The image above is a view from the north looking south over the Neoponset River where it squeezes between Commercial and Squantum points (Commercial Point is to the right (west) where the colorful tank is located and Squantum Point can be seen on the left (east) as a long spit of sand).
The larger marine facility on the right-hand side of the image is the Old Colony Yacht Club, while Thomas Marine can be seen at the top center of the image on the opposite shore. Neither facility accepts transient guests, unfortunately, but Thomas Marine doe perform repairs.
Use NOAA Chart 13270.
The approach to the Neoponset River begins back off Dorchester Bay near the main Boston shipping channel (president Roads) at waypoint N42 19.57 W71 00.00. Once you have reached this point, set a course to the southwest to intercept red nun buoy 4, keeping a safe distance from green can buoy 3 along the way. From red nun buoy 4, head farther south and follow in the following set of marks: flashing green buoy 5, red nun buoy 6, red nun buoy 8,red nun buoy 10, flashing red buoy 12, green can 1, red nun buoy 2, and then green can buoys 3 and 5 into the beginning of the river.