Inter monsoon season is normally limited to the
months of October and November. During this period, the moist Southwester
Monsoon is replaced by moist E winds over these coasts. Weak and variable winds,
with land and sea breezes prevailing, occur until the Northeast Monsoon is
established. Rainfall decreases, but thunderstorms increase slightly over these
coasts. Temperatures and relative humidity remain high. Cloudiness decreases,
except over the S of the Tenasserim coast and the W coast of Thailand. Periods
of low visibilities are rare.
Tides & Currents
The current of the entrance of the
Irrawaddy River is irregular in the fine weather season and
with the direction of wind, here the current has no apparent connection with the
rise and fall of the tide. During
November, December, and January, little or no flood current is observed S of
Alguada Reefs, except at springs.
tides along the Tenasserim coast and along the W coast of Thailand are
semidiurnal with a small diurnal inequality in both time and height. The tides
approach these coasts from the SSW and progress N. The mean spring ranges
increase from about 3m at the Burma-Thailand border to over 5.2m at Mergui.
currents flow at an average rate of 0.4 knot, with a maximum of about 0.7 knot.
The set and drift of the currents in local areas often varies from the patterns
shown below. This is due to frequent storms. Near the coast, the tidal currents
will also exert great influence and will either augment or deter the non-tidal
currents along the Tenasserim coast and along the W coast of Thailand usually
set N in January and S in February. In March the water flowing N from the Strait
of Malacca causes a N current to flow along these coasts. This flow continues
through April. In May the currents set from S to SW, except for the extreme S
part of this area where a N current still exists. The currents set S in June and
July and N from August through December.
tidal current movement is usually semidiurnal in character with some variations
in the velocities and durations of the flows. The tidal currents, as a rule, set
from ENE to NNW on the rising tide and from WSW to SSE on the falling tide.
Considerable variation in set and drift is to be expected between the many
islands off these coasts and in the confined areas and estuaries.
currents are strong along the entire coast between Tavoy Point and the
Burma-Thailand border. Between Tavoy Point and Forrest Strait, the tidal
currents usually set N on the rising tide and S on the falling tide at rates of
2 to 4 knots. The tidal currents attain a rate of 2.3 knots through Forrest
Strait. In deeper water offshore, the tidal effect becomes negligible and the
general circulation predominates. Tidal bores occur in the mouths of rivers and
There is comparatively little reliable
information concerning the tidal currents off the W coast of Thailand. These
tidal cur-rents seldom exceed 2 to 3 knots and are seldom experienced over 8
Cape Negrais to
the Sittang River
Cape Negrais (16˚02'N., 94˚12'E.), the seaward
extremity of a spur of the Arakan Yoma range, is fronted by conspicuous cliffs
which rise about 0.8 mile inland to a high summit. The cape has been reported to
be a good radar target up to 24 miles.
The coast of the Irrawaddy
Delta is low along its entire length between the Bassein River and the Sittang
River. The only high coastal ground lies on the W side of the mouth of the
Here the S extremity of the Arakan Yoma Range terminates in the
vicinity of Maw Dengi. Between the Bassein River and the China Bakir River there
are no landmarks and the navigational aids are few in number.
Between positions S of Purian Point and Baragua
Point, the 20m curve lies about 10 to 20 miles offshore. The 10m curve roughly
parallels the 20m curves at distances of about 2 to 8 miles within the latter
curve. Shoal depths of 5.5m and less lie between the 11m curve and the shore.
The 20m curves lies about 18
miles SE and 21 miles E of Baragua Point and then extends E to the vicinity of
Kalegauk Island, and approximates the outer limits of the Gulf of Martaban.
The 10m curve to the SE and E
of Baragua Point lies only about 1 to 2 miles within the 20m curve, but to the
ENE it lies between 8 and 30 miles offshore.
Those depths and dangers
which lie within the 10m curve are described together with the principal
description of that part of the coast which they front. A shoal, with a depth of
9.1m, was reported to lie about 46 miles S of Elephant Point.
vessels should not
approach within a distance of 3 miles of the coast in the vicinity of Cape
Negrais. A fringing reef and off-lying rocks make caution advisable even outside
The shallow bank, which
fronts the delta shore between Purian Point and Baragua Point, should not be
shoaled to depths of less than 18.3m.
In 1984, offshore drilling
and survey ships were operating in the area S of Irawaddy up to 45 miles
offshore. These vessels and platforms should be given a wide berth.
The coast between Cape Negrais and Maw Dengi, about
6 miles SSE, consists of a series of low, densely-wooded hills. In the vicinity
of Maw Dengi these hills have some conspicuous, reddish slopes of driven sand
which leave well-defined edges of dark foliage near their summits.
The coast between Cape
Negrais and Maw Dengi is fringed by reefs and shoal patches which extend up to
1.3 miles off-shore in places.
(Pagoda Point) (15˚57'N., 94˚15'E.), about 30m
high and flat, terminates in a bare bluff. A pagoda lies on the point and is
visible above the trees. A small 2.7m high obelisk lies on the reef on the SE
extremity of Maw Dengi.
A shoal, with depths of 5.5m
and less, lies up to 0.5 mile S and W respectively of the point. A detached 5.5m
patch lies about 1 mile W of the point.
The Irrawaddy River rises in the N part of Burma and
generally flows to the S. Augmented by numerous tributaries, the Irrawaddy River
flows into the Bay of Bengal by way of several channels through an extensive
delta lying approximately between the meridians of 94˚15'E and 96˚50'E. This
delta is being constantly extended seaward by the deposit of silt. Many low
islands are formed near its seaward extremity by tidal backwaters and smaller
cross channels which connect with the main channels.
The only channels through the
Irrawaddy Delta used by ocean-going vessels are the Bassein River and the
Rangoon River, the furthest W and E, respectively.
Approaches to the Bassein River
Dengi, which lies on the NW side of the entrance of the Bassein (Pathein)River,
has been previously described in paragraph 8.2.
Purian Point (15˚50'N., 94˚24'E.), low and backed by a group of trees 22.9m
high, lies on the SE side of the entrance of the Bassein River. White sandstone
low bluffs extend 1.5 miles NE from the point. Higher bluffs begin about 1 mile
NNE of the point and extend to the N for about 1.3 miles.
Tides in the entrance of the Bassein River are semidiurnal.
tidal currents set strongly across Phaeton Shoals; the flood current sets E and
the ebb current sets W.
About 1 mile N of Thamihla Kyun the tidal currents are rotary during spring
tides. At the beginning of the flood tide, the current sets 152˚ and changes
through 090˚, so that at the end of the flood it sets about 057˚. With the
commencement of the ebb tide, the current sets about 315˚ and changes through
270˚, setting at the end about 225˚. The greatest velocity, 1.5 knots, is
attained during the second and third quarters of each tide.
the entrance bar, the flood current sets about E and the ebb current sets
between SW and SSW at velocities of 1.5 to 3.5 knots during spring tides. At
spring tides, during the rainy season, the ebb current may reach a velocity of 6
Depths—Limitations.—.Alguada Reef (15˚42'N., 94˚ 12'E.), almost awash at HWS,
has detached sunken rocks extending a considerable distance from it. Hugh Rose
Rock, which is awash, lies off the N end of the reef about 2.5 miles NNE of the
light, which lies near the SW end of the reef. A 4.1m patch lies about 1.3 miles
S of the light. Depths of 10.1m and less extend about 0.8 miles farther SW.
Alguada Reef Light bearing 092˚
Caution.—Less water than charted has been reported to lie in an area between 19
miles W and 18.5 miles SSW of Alguada Reef Light.
Several detached shoal patches, with depths of 5.5 to 14.6m, have been reported
to lie within a 1 mile radius of a position about 17 miles WNW of Alguada Reef
Phaeton Shoals (15˚47'N., 94˚14'E.), a group of shoal patches with a least depth
of 4.3m and 2 miles in extent, lie centered about 10.3 miles S of Maw Dengi.
Depths of 11 to 18.3m surround these shoals.
Thamihla Kyun (15˚52'N., 94˚17'E.), flat and wooded, lies about 5.5 miles SSE of
Maw Dengi. Reefs and shoals extend about 2 miles SSW and 0.8 mile NE from the
island. Rocky patches, with a least depth of 7.9m, extend about 0.8 mile W from
the island. Thamihla Kyun has been reported to be a good radar target up to 18
Baroni Rock (15˚52'N., 94˚17'E.), with a least depth of 4.9m, lies about 0.5
mile NE of the N end of Thamihla Kyun.
Haing Gyi Shoal (15˚57'N., 94˚17'E.), with depths of 5.5m and less, extends
about 5.5 miles S into the river entrance from the shore about 3.3 miles NE of
Depths in the channel between Thamihla Kyun and the shore bank extending about 6
miles WNW from Purian Point range from 6.1 to 9.1m. Depths in the approach to
and within the entrance channel W and N of Thamihla Kyun range from 18.3 to
Pilotage, is compulsory. Pilots will board off the pilot station,
located about 0.3 mile SE of Dalhousie Point.
During the Northeast Monsoon, if no pilot is readily avail-able, a vessel should
proceed to the anchorage SE of Thamihla Kyun.
To avoid delay, the vessel’s ETA should be sent to the Port Officer at Bassein
at least 48 hours prior to arrival.
Directions. Vessels approaching the entrance of the Bassein River from the S
should not approach Alguada Light closer than 3 miles. The summit of Haing Gyi
Kyun bearing 020˚, and well open E of Thamihla Kyun, leads about 0.5 mile E of
the easternmost shoal depths of Alguada Reefs and Phaeton Shoals. Having passed
Phaeton Shoals, course should be shaped for the anchorage SE of Thamihla Kyun.
Care should be taken to allow for the tidal current.
course of 350˚ should be steered to pass E of the two lighted buoys E of
Thamihla Kyun, passing N of Broni Rock and then altering course to the NE,
entering the river between Haing Gyi Shoal and Purian Bank. When 3 miles S of
Rocky Point, alter course NNE and pass not less than 0.2 mile W of Burgess Rock.
Having cleared that rock course should be altered to the NE and then proceed to
the anchorage off the pilot station at Dalhousie Point.
Vessels approaching the entrance of the river from the W, if proceeding to the
anchorage SE of Thamihla Kyun, should pass about 1 mile N of the island so as to
clear the shoal depths N of Baroni Rock. When Thamihla Kyun Light bears 206˚,
steer for the anchorage. This approach is not recommended during the Southwest
Monsoon, when the vessel should proceed directly to the anchorage off the pilot
Anchorage. During the Northeast Monsoon, good anchor-age can be taken, in
depths of 8.2 to 9.1m, about 1 mile SE of Thamihla Kyun. When anchored in this
position, the summit on Haing Gyi Kyun should bear about 016˚ and the light
structure on Thamihla Kyun about 322˚.
River to Pathein
The Bassein River, the W of the channels
leading through the Irrawaddy Delta, is the means of access for ocean
going vessels calling at the port of Bassein, about 75 miles
above the river's entrance. The river
entrance has been
reported to be a good radar tar-get up to 15 miles.
Winds, Weather. The weather generally is hot and humid. The heavy rainfall,
which sometimes exceeds 2,700mm annually, occurs during the Southwest Monsoon
between June and September.
Storm and weather signals are displayed at Thamihla Kyun in accordance with
the Indian Extended System. The Extended System is in use at Bassein; the port
receives information but no signals are displayed.
Tides, Currents. Large diurnal inequalities and seasonal variations best
describe the tides at Bassein.
Tidal currents at springs attain velocities of 1.5 to 2 knots during the flood
and up to 3 knots during the ebb. During freshets the velocity may reach 5
tide gauge lies on Ashby Rockys near the W bank of the river and just N of
Panmawaddy Flat. A white cage topmark and red, black, and white plaques from the
top downward, respectively, mark the tide gauge. Each plaque represents 0.3m;
the lower edge of the topmost white plaque marks the 7.9m level.
Depths, Limitations. The least depth in the channel over the bar which lies
across the entrance of the Bassein River is about 6.1m. The bar lies between the
shallow flat close E of the Maw Dengi and the W and SW edges of Purian Bank. The
channel over the bar leads between Purian Bank to the E and Haing Gyi Shoal to
The controlling depth in the river channel between Thamihla Kyun and Bassein is
the depth over Panmawaddy Flat. In 1964, the channel was dredged to 5.2m.
Changes in the channel are frequent and the navigational aids are scarce. This
lack of navigational aids makes navigation at night impracticable. Due to the
narrowness of the river at Bassein, single-screw vessels exceeding a length of
137m and twin-screw vessels exceeding a length of 145m are advised not to
attempt the upriver passage.
Deep, draft vessels await HW in order to cross the entrance bar; HW is
essential to cross Panmawaddy Flat. Successive periods of HW are usually
required and the passage in both directions ordinarily takes more than a day.
In heavy weather, the best time to cross the bar is between half tide and 2
hours after HW at Thamihla Kyun. During the Southwest Monsoon, a clearance of at
least 1.2m under the keel is considered necessary when crossing the entrance
Haing Gyi Kyun (16˚00'N., 94˚19'E.), an island with a 135m hugh densely-wooded
summit on its NE extremity, lies with Rocky Point, its S extremity, about 5
miles ENE of Maw Dengi. A 22m high tree on Southeast Point, about 0.3 mile NNE
of Rocky Point, is a good mark.
Rock (15˚59'N., 94˚20'E.), with a depth of less than 1.8m, lies about 0.4 mile
off the E side of Haing Gyi Kyun. Foul ground extends about 0.4 mile E and S
from the rock.
bank of the river between Purian Point and Ward Point, about 10.8 miles to the
N, forms the SE side of the river entrance.
Purian Bank (15˚53'N., 94˚22'E.) lies within the limits of the shore bank which
extends about 6 miles NW and then 9.8 miles NE to Ward Point. Depths over this
bank and shoal are less than 5.5m.
Burgess Rock (16˚00'N., 94˚22'E.), with a least depth of 5.5m, lies about in the
middle of the main fairway, about 2.8 miles WSW of Ward Point.
Dalhousie Point, on the W bank about 2.5 miles N of Ward Point, is marked by
Long Sand (16˚04'N., 94˚28'E.), which consists of two is-lands lying on a long,
narrow shoal, lies about 3 miles ENE of Ward Point. Shoal depths extend about 3
miles WSW and NNE from Long Sand.
Tazingyun (16˚09'N., 94˚32'E.), which consists of two is-lands close together,
lies on the E side of the fairway about 4 miles above Long Sand.
Ransom Reach (16˚17'N., 94˚39'E.) is entered about 7.5 miles upriver from
Tazingyun. Sesostris Rocks lie on the W side of the reach; two small islands lie
on the E side of the reach.
Sinswe Kyun (16˚23'N., 94˚42'E.) lies in mid-channel at the N end of Ransom
Reach. Alexander Rock, with a least depth of 4.6m, lies in mid-channel about 0.5
mile S of Sinswe Kyun. Pariah Rock, with a depth of less than 1.8m, lies about
1.8 miles N of Sinswe Kyun at the outer edge of Enterprise Flat.
Amazon Point (16˚29'N., 94˚41'E.), on the E bank of the river about 5.3 miles N
of Sinswe Kyun, marks the S entrance point of the shallow Panmawaddy River.
Panmawaddy Flat, with a least depth of 0.3m and surrounded by shoal depths of
5.5m and less, lies with its N end about 1.3 miles SW of Amazon Point.
Cockatoo Point (16˚30'N., 94˚40'E.), on the W bank of the river, lies 1.8 miles
NW of Amazon Point. Ashby Rocks, marked by a beacon, lie close N of Cockatoo
Point (16˚32'N., 94˚41'E.) lies about 2.8 miles NNW of Amazon Point. Elbow
Shoal, as defined by the 6m curve, lies about 1 mile SSW of Elbow Point at the
outer end of a spit extending from the shore.
Rangoon Creek, on the SE side of Junction Reach, flows into the Bassein River
about 8.5 miles above the entrance of the Panmawaddy River. Two conspicuous
masts support telegraph wires across its entrance.
Anchorage can be taken, in depths of 9.1 to 10.1m, about 1 mile E of
Vessels suspected of or infected with yellow fever must anchor off Dalhousie
Point, not less than 0.5 mile distant from the LW line. Vessels with plague or
cholera on board may anchor off Takaing Pagoda on the W bank of the river about
2 miles below Bassein. Vessels with other diseases on board may anchor anywhere
below the wharves.