Malacca Banks, with deep channels to the W and E, lie in the fairway of the approach.
Grant Channel and Sutherland Channel are safer to use than the channels between the banks, as the mariner is able to accurately fix his position from the objects on the coast; Sutherland Channel should be used only by those with local knowledge.
The S part of the gulf is deep, but the N part is encumbered with sand banks, which frequently change because of the force of the bores and freshets from the rivers.
Deep-draft vessels can proceed up the gulf as far as Piram Island, about 28 miles NNE of Gopnath Point. Local knowledge is necessary for vessels navigating above Gogha, about 6 miles NW of Piram Island.
Considerable shoaling is reported in the entrance of the Gulf of Cambay and mariners should navigate with caution in this vicinity.
The sand and banks in the upper part of the gulf are subject to great alterations. Any directions for navigating this area must be considered as general only; local knowledge is necessary.
Malacca Banks is the general name for four long narrow shoals lying in and obstructing the entrance of the Gulf of Cambay, between the parallels of 20°20'N and 21°20'N. These shoals, named in order from W, are Western Bank, Narbada Bank, Breaker Bank, and Eastern Bank.
Deep channels are between these shoals, but they are narrow at their N ends, and it is inadvisable to use them.
Western Bank dries in places.
Grant Channel, between Western Bank and the coast NW, is steep-to on both sides, with general depths of 11.3 to 27m. bottom is sand toward the bank and mud toward the Channel off the N end of Western Bank.
Depths in Grant Channel between Gopnath Point and Western Bank, 6 miles SSE of Gopnath Point, were reported (2002) to be 1 to 1.5m less than charted.
Narbada Bank has a large area of drying sand near its center.
Breaker Bank has a long sand bank near its center, which may be seen a long distance from the masthead when the sun shines on it at high water neaps, but it is submerged at high water springs. Depths of 2.7 to 3.3m lie at the N end of Breaker Bank, about 16 miles ENE of Gopnath Point; a drying patch was reported (1954) in this vicinity. A dangerous wreck lies about 5 miles SW of Breaker Bank.
Eastern Bank has several shoal patches, some of which dry.
Because the depths are deep within 0.2 mile of these shoal patches in many places, soundings give little warning of the approach to these dangers.
Sutherland Channel, between Eastern Bank and the coast E, is about 2.5 miles wide at its narrowest part, WNW of Suvali Point. Two lighterage areas, one for general cargo and one for chemical and LPG cargo, which are best seen on the chart, are located about 5 miles W of Suvali Point.
Shoaling, including a drying patch about 300m wide, has been reported (2003, 2006) in an area extending from 2 to 3 miles SW of the SW corner of the charted General Lighterage Area.
The coast of the W side of the head of the gulf from Johnston Point to the entrance of the Bhadar River, about 26 miles NNE, is composed chiefly of mangrove jungle, extending several miles inland. The sand bank fronting this coast dries and extends from 1 mile to 4 miles offshore.
Mal Bank, the S end of which lies about 7.5 miles E of Johnston Point, is a large sand bank lying in the middle of the head of the gulf, and extends about 4 miles N.
There are channels on the either side of Mal Bank, each about 1 mile wide in the fairway, but local knowledge is necessary.
Malcolm Channel is the W channel.
Khambhat Channel leads NE into the estuary of the Mahi River from the N end of Mal Bank. Khambhat, the chief town in the area, lies on the N side of the estuary of the Mahi River.