Brant Rock is a village about 5 miles southward of Fourth Cliff. The village derives its name from Brant Rock, a distinctive bare rocky islet about 300 yards offshore that is joined to the shore by a stone jetty. A square concrete tower in the village is very prominent. For about 1 mile south of Brant Rock to the entrance of Green Harbor River, foul ground extends offshore for nearly 1.5 miles to Farnham Rock, which is covered 14 feet. A lighted bell buoy is just eastward of the rock.
Green Harbor River has its entrance west of Blackmans Point at the southern end of Green Harbor Point. Bartlett Rock, which uncovers 2 feet, and Howland Ledge, covered 7 feet and marked by a buoy, are 0.6 and 1.2 miles eastward of the entrance, respectively. An obstruction reported to be covered 6 feet is about 275 yards south-southeast of Bartlett Rock. In 1987, an obstruction was reported 200 yards south of Bartlett Rock in about 42°04’34.2″N., 70°37’49.0″W. Jetties are on each side of the entrance; the east jetty is marked by a light. A channel leads to a turning basin about 0.6 mile above the seaward ends of the jetties. An anchorage basin is on the east side of the channel off the town wharf. Lighted and unlighted buoys mark the entrance and channel inside.
Local fishermen adjust their arrival and departure times so that they are not in the entrance channel 90 minutes on either side of low water. A current flowing out of the entrance channel during the falling tide reportedly sets up a rip just inside the entrance jetties.
The town wharf and a marina are on the east bank about 0.4 mile above the jetties. The facilities have approach and alongside depths of 6 feet. Berths, electricity, gasoline, diesel fuel, water, ice, sewage pumpout, launching ramps, a 12.5-ton lift, storage and hull and engine repairs are available.
Green Harbor is a small village on the west side of the river. Four prominent radio towers are just southwest of the village and 5 miles northward of the entrance to Plymouth Bay. A marina and the Green Harbor Yacht Club are on the west bank near the head of the harbor close southward of the causeway. Berthage, electricity, gasoline, water, marine supplies and a small-craft launching ramp are available at the marina. The service float has 6 feet reported alongside. A 15-ton mobile hoist can haul out vessels for hull, engine, electrical and electronic repairs and for open winter storage.
High Pine Ledge, awash at low water and marked on its easterly side by a buoy, is about 0.8 mile off Duxbury Beach and 2 miles northward of Plymouth Light. The ledge extends from the buoy nearly to the shore; vessels should not attempt to pass westward of the buoy.
Plymouth Bay is about 20 miles southeastward of Minots Ledge Light. From its entrance, between Gurnet Point and Rocky Point, it extends about 2.5 miles westward to Plymouth Beach. Warren Cove, the southern part of Plymouth Bay, is sometimes used as a temporary anchorage.
Plymouth Harbor is about 1 mile wide at its northern end, gradually narrowing to its southern end. Most of the harbor is dry at low water. The channels in Plymouth Harbor and tributaries usually have soft bottoms. The channel through the entrance is well marked and easily followed in clear weather.
Plymouth is a town on the southwestern side of Plymouth Harbor. There is some waterborne commerce at Plymouth, most of it being fishing vessels and excursion boats. At the town wharf, fishing craft unload fish, scallops and lobsters for shipment to New York and southern markets.
Duxbury Bay is between Duxbury Beach on the east, Saquish Neck on the southeast, and the mainland on the west. It is about 3 miles long, with an average width of 2 miles. The bay is full of flats, mostly bare at low water, through which are several narrow and crooked channels. Shoals covered in spots by little water rise abruptly on both sides of these channels, and at low water the shoal edges are usually revealed by discolored water.
Duxbury, a town on the west shore of the bay, is a summer yachting and residential resort.
Kingston Bay, between the mainland and the western point of Duxbury Bay, is about 1.5 miles wide and has numerous flats. Caution and local knowledge are advised. The village of Kingston is nearly 1 mile back from its western shore on Jones River. This bay is of little importance either as a harbor or port.
Prominent features
Gurnet Point, on the north side of the entrance to the bay, is marked by Plymouth Light (42°00’13″N., 70°36’02″W.), 102 feet above the water and shown from a white octagonal pyramidal tower with a white dwelling. A sound signal at the light is operated by keying the microphone five times consecutively on VHF-FM channel 83A.
Rocky Point, on the south side of the entrance, is about 3 miles south of Gurnet Point. The rectangular reactor building of the Pilgrim Nuclear Power Station southeast of Rocky Point is conspicuous.
Duxbury Pier Light (41°59’15″N., 70°38’55″W.), 35 feet above the water, is shown from a brown conical tower with white upper half; a sound signal is at the light and is activated by keying the microphone five times consecutively on VHF-FM channel 83A. The light, locally known as “Bug Light,” marks the north side of the channel and the south end of the shoal between the main channel and Cowyard.
Captains Hill, on the peninsula between Duxbury and Kingston Bays, is about 200 feet high. On its summit is Standish Monument, 291 feet high, which can be seen from all directions when approaching the harbor. Manomet Hill, about 5 miles southward of Gurnet Point, is 390 feet high, heavily wooded, and conspicuous in approaching the entrance.
The monument at Plymouth and a standpipe are conspicuous. A lookout tower on Monks Hill (see chart 13246), about 2.5 miles westward of Plymouth, and the buildings and stack of the former cordage company at Cordage are prominent.
Plymouth Harbor Channel is a dredged channel which leads southward from Plymouth Bay from a point 0.3 mile southwestward of Duxbury Pier Light to the State Pier at Plymouth, about 2 miles above the entrance, thence to a turning basin off the Town Wharf, about 0.2 mile above the State Pier. An anchorage basin, protected by a breakwater on the north and northeast sides, is in the harbor. A Federal project provides for a depth of 15 feet in the dredged channel to and in the turning basin; the anchorage basin in the harbor has a project depth of 8 feet. The channel is marked by a light with a white sector marking the entrance, buoys, another light and private lighted ranges. The range structures are difficult to identify in the daytime.
A channel leads from the southerly end of Cowyard, westward of Duxbury Pier Light to the wharf of the former Plymouth Cordage Company, about 1.5 miles northwest of the Plymouth Town Wharf. The channel is marked by buoys. In 1964, shoaling to 9 feet was reported in the channel for about 0.6 mile westward of The Nummet. The section of the channel approaching the wharf is privately marked.
Duxbury Bay Channels
Where the several bay channels come together in the locality westward of Duxbury Pier Light, a channel extends northward up Duxbury Bay until west of Clarks Island. This channel, Cowyard, about 200 yards wide and with depths of 20 to 35 feet, offers good anchorage for small craft. The channel splits at a point westward of Clarks Island. The eastern branch, Beach Channel, is reported to be marked by private seasonal buoys and continues up the easterly side of Duxbury Bay. A highway bridge at Powder Point, at the junction of Back River with Duxbury Bay, has a 25-foot fixed span with a clearance of 5 feet.
The western branch has a deep natural channel for about 1.5 miles from the area of Clarks Island northward of the fork in the channel. The channel to this point is buoyed and easily followed and at this point connects with a dredged channel that leads northwesterly to an anchorage basin at the village of Duxbury. The dredged channel, marked by buoys, has a project depth of 8 feet.
Anchorages
Vessels waiting to enter may anchor on the north side of the entrance channel southeast of Saquish Head and eastward of the buoy marking the extremity of the shoal that makes southward from that head, or they may proceed to the intersection of the bay channels and anchor where the swinging room is greatest, between 500 and 600 yards westward of Duxbury Pier Light.
The best anchorage is in Cowyard, but small lightdraft vessels often find good anchorage under the lee of Plymouth Beach. Yachts and small craft anchor in the anchorage basin off the wharves at Plymouth. In 1983, the basin had depths of 8 feet except for shoaling in the northwest corner and along the north edge.
Dangers
Outer Tautog Rock, with 2 feet over it, is part of an unmarked shoal extending about 0.5 mile northward of Rocky Point.
Browns Bank is in the central part of Plymouth Bay. Northward of Browns Bank, and between it and Saquish Neck and Saquish Head, is the entrance channel to Plymouth Harbor, Kingston Bay and Duxbury Bay.
The unmarked channels in Kingston Bay and Duxbury Bay are narrow and crooked and lead between flats bare or nearly so at low water; local knowledge is required to carry the best water. The best time for strangers to navigate these channels inside the harbor is at low water when the flats are visible.
Current
In the channel between Gurnet Point and Duxbury Pier the tidal current at strength has a velocity of about 1.4 knots. The set is generally in the direction of the channel; but the ebb sets southward and eastward across Browns Bank, while the flood sets northward and westward above Saquish Head, and sweeps strongly around Duxbury Pier Light northward into Cowyard.
Ice often closes the harbor from about the first of January through February. When there is ice in the harbor, Cowyard is not a safe anchorage. In winter the safest anchorage from ice is in the channel southward or eastward of Saquish Head, and vessels sometimes go to sea on account of drift ice at this anchorage. Westerly winds tend to carry the ice out in fields. Normally the channel to the pier at Cordage is open to traffic all winter. Northwesterly winds sometimes bring ice in, but southerly winds clear it out.
Harbor regulations
The several towns have harbor regulations that are enforced by the various harbormasters, who control the moorings. The Plymouth and Duxbury harbormasters maintain offices on their respective town wharves. The speed limit is 6 miles per hour in Plymouth Harbor.
Wharves
Fishing vessels discharge their catches at the town wharf at Plymouth and Duxbury. The town wharf at Plymouth has a reported 10 feet alongside its service float; a small-craft launching ramp is close by. The State Pier at Plymouth has 12 feet alongside. The replica of the MAYFLOWER is berthed on the south side of the State Pier.
Supplies
Gasoline, diesel fuel and water are available at the Plymouth and Duxbury town wharves and at most of the marinas and boatyards. Ice, provisions, bottled gas and marine supplies are available at Plymouth and Duxbury. Motels, hotels, restaurants, laundromats, shops and markets are in the area.
Repairs
There is a boatyard at Plymouth, one at North Plymouth and several at Duxbury. These facilities can make hull, engine and electronic repairs and have storage facilities and marine supplies. The boatyard at Plymouth, about 0.2 mile southeastward of the State Pier, has a 10- ton crane, 60-ton boat lift, berths with electricity, gasoline and diesel fuel. The largest marine railway at Duxbury can handle craft up to 50 feet in length; lifts up to 40 tons are also available. The boatyard at North Plymouth, close southward of the pier at Cordage, has a 75-foot marine railway and a 40-ton lift.
Small-craft facilities
There are well-equipped marinas at Duxbury and Plymouth at which gasoline and diesel fuel, water, berthing with electricity, pump-out facilities and most yacht services are available. Small-boat launching ramps, both public and private, are available. The Duxbury Yacht Club, at the northwest corner of the turning basin at Duxbury, and the Plymouth Yacht Club, about 0.3 mile southward of the State Pier at Plymouth, offer various services to visiting yachtsmen. Gasoline is available at the Plymouth Yacht Club float.