The following extracts are drawn from The Australia Pilot, volume 4, published 1920 and the depth figures were compiled after correlating with present day tide data.
When Koombana departed Port Hedland for the last time, the depth over the bar was 19 ft., 1 ft. short of high water springs.
There is a lag between full or new moon and high water springs (new moon in this case, 18 March, 1912). Koombana was running a day late and another day's delay would have incurred a further level reduction to 18.6 ft.. Three days after high water springs the level would have dropped significantly to 17.6 ft..
"I don't like the glass,"
was Captain Allen's remark,
"and another 24 hours
here will not matter."
The above figures justify this alleged statement made by Captain Allen. The 24 hours in question would have coincided with 18.6 ft. over the bar and if weather conditions had potentially stabilised by then (squall rather than cyclone - see further discussion below) Captain Allen could have departed with just the after-peak empty; comfortably cleared the bar and filled the one tank in calmer waters within a reasonable timeframe. 48 hours, however, would have produced 17.6 ft. and increased the potential for being neaped.
The day before high water springs the level over the bar would have been in the region of 19.6 ft.; two days prior, 18.5 ft. and three days prior, 17 ft. !! Port Hedland, therefore, offered a very narrow window of opportunity for a steamer Koombana's size and the schedule had to be adhered to as far as humanly possible.
In fact under normal conditions emphasis would have been placed on arriving the day before high water springs and making a smart exit the following day (19.6 ft. and 20 ft. over the bar). Extending this time frame required emptying tanks(s) and hoping for a calm sea at the port's entrance. This must surely have created enormous pressure for Captain Allen and we know that he had his fair share of bar strikes attempting to cross the bar without emptying tanks.
Tides - It is high water in Roebuck Bay, full and change, at 11 h; springs rise 28 feet, neaps 18 feet. The highest tides occur on the second or third days after full and change, and are subject to diurnal inequality. The day tides rise 18 inches (July) higher than the night tides.
Broome on the other hand offered better draft flexibility (max. 28 ft.), almost 5 days on either side of high water springs (down to 18 ft.). However, the tide swing is dramatic, and around high water springs the low tide level was actually a negative figure, minus 3 ft., which translated into Koombana sitting high and dry on the mud with water as far as a mile off.
Added to this, the daily times for spring tide migrated from about 12 midday through the afternoon to about 4 p.m. during the course of 5 days. This would have impacted arrivals and departures, incurring delays waiting out at sea for high tide and access.
Port Hedland harbour:
The head, and a considerable breadth of sand mud flats on either side, dry off at low water, and the deep water channel, above 3 fathoms (18 ft.), nowhere exceeds 300 yards across. The entrance between Hunt and Airey Points is 1/3 mile wide, with sand hills on both sides, generally covered with spinifex grass; the land within is low, marshy, and intersected by creeks, mostly dry at low water; they have not been surveyed other than as charted.
18 ft. in the channel could be boosted to as much as 40 ft. during high water springs.
The Bar, 2 miles from the harbor mouth, consisting of rock thinly overlaid with sand, has a least depth of 1 foot at springs, and then generally breaks. There is also an inner bar with 1 fathom (6 ft.) water, 1,500 yards northeastward of Hunt Point. Vessels of 18 feet draft may cross at high water springs, subject to the tide signals shown.
Koombana was reported to have had an aft draft of 19 ft. which, theoretically, would have disqualified her from crossing the bar. As it was, draft did not exceed 16 ft. aft, and for very good reason considering there was a big sea, gale and turbulence over the bar.
Middle Bank Buoy - The Middle Bank, southward of Hunt Point, divides the entrance into two channels, that to the westward being the deeper but more tortuous. Middle Bank is about 800 yards in length, and it dries over a length of about 700 yards and northward and westward of the buoy. Sand and mud flats extend a considerable distance from both shores, reducing the fairways to narrow limits.
An extremely challenging port to negotiate.
Occasional Light - A black spar buoy, with staff and cage, from which an occasional fixed red light is exhibited, is moored on the Middle Bank at about 100 yards within its northern drying edge.
Beacons and Range marks - The channel is marked by red beacons on the starboard hand, black beacons on the port hand.
Tidal signals - tidal signals are shown from the tidal flagstaff, as follows:
A ball is hoisted at the head of the staff when the tide is rising, and a red burgee when the tide falling. One ball on the western yardarm (steel tower) indicates 19 feet or more (over the bar).
Tides - High water interval at Port Hedland is 10 h. 50 m.; mean range 12 feet 3 inches, springs rise 19 feet 3 inches. Equinoctial springs rise 22 to 24 feet.
Tidal currents in the harbor run 3 to 4 knots. The ebb is the strongest and at the highest tides may attain 6 knots. At the anchorage the flood runs westward, ebb eastward, from 2 to 2 1/2 knots an hour.
It is not surprising that Captain Allen insisted that a lugger be removed from the channel before he made his run for open sea. In such light condition with the propeller and rudder not fully submerged (decreased thrust and manoeuverability), contending with a powerful (up to) 6 knot current and narrow channel, this was a dangerous time for the large steamer.
Jetty - At Mangrove Point there is a jetty about 700 feet long, where two steamers can berth; there are cattle yards within it. Vessels can discharge into railway trucks. At spring tides the currents run strongly past and vessels should securely moor with anchors as well as by shorefasts to the jetty.
Anchorages - Anchorage outside the bar, to await tide for entering, may be had in 3 fathoms (18 ft.), about 3 miles from shore near the line of the range marks. Small vessels may anchor 1/2 mile nearer shore in 2 1/2 fathoms.
It was at this position 3 miles out that Captain Allen attempted to fill ballast tanks. Again, 3 fathoms, 18 ft., translated into as much as 40 ft. during high water springs.
The best anchorage in the harbour is about 800 yards northward of Harriet Point, in 6 fathoms (not possible today), sand; the holding ground is not good above this. Vessels over 200 feet in length should moor head and stern, there being insufficient room to swing. Two vessels can berth alongside the jetty, as before mentioned.
Directions - Within 1/2 hour on either side of high water is the best time to enter or leave; in narrow parts, at half tide, the currents may run 6 knots. An anchor should always be ready. Southward of Hunt Point, the western point of the entrance, the channel westward of Middle Bank has not less than 4 fathoms at low water, and is deep and well marked by the range beacons.
High water was at 10 h 50. Koombana departed at 10 h 20, half an hour before, exactly as instructed.
When there is sufficient water to cross the bar, the passage eastward of Middle Bank, also well marked, may be taken, thus avoiding the sharp turns and oblique tidal currents of the western channel.
The two range beacons for the bar, namely, the tidal signal staff and Lumsden Beacon, in range bearing 203 degrees, lead over the bar, and the conspicuous dark mangrove clump westward of Harriet Point should be steered for when bearing 220 degrees.
Vessels can only enter at night with thorough local knowledge; a red light is shown from the buoy on Middle Bank when required.
The following images are an attempt to transpose the instructions onto present day Port Hedland, with limitations acknowledged.
 |
| The black circle represents the position of the inner bar as per the extract. Note the position coincides with the apex of the sand bank as marked and is slightly west of the present day narrow shipping channel. |
 |
| The black circle indicates the position 3 miles out where Koombana would have filled tanks. The present day shipping channel bears initially northwestward, whereas Koombana would initially have sailed due north. |
Western Mail, 20 September, 1902.
A PORT HEDLAND HARBOUR
OBSTRUCTION.
Port Hedland, September 16.
If Port Hedland is to remain a port
for steamers to take shelter in, the sand-
bar at the entrance to the channel will
have to be dredged. The bar is 200yds.
long and 30yds. wide, and it is extending
rapidly. It is a common occurrence
for steamers to strike on the bar and
remain aground for 12 hours, or until the
next tide. The s.s. Minilya, on her last
visit here, was fast on the bar for an
hour coming in, and for 12 hours on her
way out. Every vessel that is in the Nor'-
West trade has been aground here. The
dredge Priestman would, in the opinion
of visiting ship masters, do all the work
that would be necessary to make the bar
navigable. The expense of the dredging
would, it is believed, be of small account
in proportion to the advantages to
be derived.
 |
| The 'bar' as described above. |
Kalgoorlie Miner, 21 July, 1908
PORT HEDLAND HARBOUR.
July 20.
The passage into Port Hedland
Harbour is in need of serious
attention. Every ship captained
by a man new to the coast or
unused to local conditions of
tide, etc., sticks on the inner bar.
The last boat, the Dilkera, suffered
some damage on the bar, and had
to have Lloyds' surveyors to
report before leaving the harbour.
 |
| SS Dilkera - courtesy Flotilla Australia. Built 1902 2667 gross tons length 326 ft. beam 45 ft. 3 inches draft 21 ft. 8 inches - excessive for Port Hedland! |
14 July, 1912, the following discovery was made:
'Bullara, on passage from Cossack to Port Hedland,
passed derelict, appeared to be submerged bilge
of vessel, 15Oft. or 200ft. long, in latitude 20 deg.
10 min. south and 118 deg. 3 min. east.'
It was thought that the bilge section came from the wrecked Koombana and if so, there is an important inference to be made. Had Koombana sustained significant latent damage to her hull subsequent to the documented bar strikes within the 6 months leading up to the disaster? And if so, had she suffered some form of catastrophic hull failure in the rough seas? Or was it simply a case of damage sustained striking the seabed? Only time will tell if the wreck, once found, gives up her secrets.
The Pilbarra Goldfields News, Saturday 30 May, 1903.
PORT HEDLAND BAR
Perth, May: 25,
Captain Frank Pitts, of the steamer
Sultan, warmly supports, Mr. Isdell in
his efforts to have the bar at Port
Hedland removed.
In a conversation with a Herald
reporter, Captain Pitts stated that the
bar was absolutely dangerous and at
ebb tide it was some feet out of the
water. There was a channel alongside
the bar which was less than 60 feet
wide. It was of rock and should a
vessel strike it she would undoubtedly
be lost. None of the shipmasters trading
to Port Hedland cared about using
the channel, and only did so because
they were compelled to. For his part,
he always used another channel, which
was more difficult, but in which there
was a sandy spit and not so much
rock. Now that larger boats were being
employed in the trade, the work of
removing the bar was rendered more
necessary.
The West Australia, 26 May, 1920.
PORT HEDLAND.
Port Hedland, May 25.
Passengers by the Bambra say that
they had to wait about four hours on
the Broome jetty. When the vessel
arrived off Port Hedland in the early hours
of this morning there was some difficulty
in getting into the lifeboats to come
ashore. A stiff easterly wind was blowing
and when the boats were returning to the
vessel there was a fair sea. One boat
was able to get within a few hundred
yards of the Bambra when the steamer
lifted her anchor and picked the boat up.
The other boat was picked up by the
steamer about a couple of miles away.
The simple fact of the matter. Missing the spring tide window prevented steamers such as Bambra accessing Port Hedland.
The West Australian, 10 April, 1918.
A PORT HEDLAND COMPLAINT.
Port Hedland, April 9.
Owing to the steamer Charon not calling
here on her next southward trip, a period
of about seven weeks will elapse between
the last mail and the next. If the Charon
called at Broome, letters could be posted
here to catch the Minderoo on her next
trip north and they could then be sent
on. But it is said that the Charon's first
port of call is Carnarvon.
Enormous pressure!
The Phillips River Times, 3 March, 1906.
Port Hedland
(From our own Correspondent.) .
Our Port Hedland correspondent
writes, under date February 19, as
follows :—
Several very unpleasant dust storms
swept over the town last week, and
another this morning. Eighteen
points of rain were registered.
Last Friday the mail boat Tyrian
arrived in the roads and refused to
approach the jetty, notwithstanding
the tide gauge registered 19ft. of water,
which was signalled to the steamer.
The captain, however, preferred the
delay of sending in two of the ship's
boats with the passengers and mails.
One boat leaked to such an extent that
on arriving at the jetty it was nearly
half full of water. Much indignation
was shown by the passengers and
shippers towards the action adopted by
the captain without a reasonable cause
as the steamer was only drawing
15ft. 3in.
There can be no denying the simple fact that Port Hedland was a challenging port to access even if the steamer in question had a comfortable, 3 ft. 9 in. clearance.
Koombana had a 3 ft. clearance 20 March, 1912.
This was not comfortable.
It never was....
 |
| courtesy Flotilla Australia |
SQUALLS vs. CYCLONES.
Koombana, fully ballasted, was to reveal her weakness during a Nor'West squall, February, 1910.
'Just before reaching Hedland we struck a squall and the ship lay over at an angle of 45 degrees and was quite a long time before straightening up.' (Koombana Days - Annie Boyd).
The following extract courtesy the Hathi Trust, Australia Pilot, 1920, describes such squalls:
During the Northwest monsoon, however, strong gales from the northwestward at times blow upon the coast but do not appear to be frequent. The strongest winds at this season are what may be properly termed as hurricane squalls, from between east-southeastward and northeastward; they mostly occur between sunset and sunrise, and rarely last more than a few hours, nor extend over a large area, and generally give ample warning of their approach by a heavy bank of clouds, with much lightening, between northeastward and southeastward. The breeze comes on almost immediately and with considerable violence, accompanied with rain in torrents and a short chopping sea. The rate of progress of these storms on the northwestern coast of Australia is estimated to be from 11 to 14 miles per hour, travelling from northeastward to southwestward, approximately following the coastline. They are always accompanied by abundant rain, with low dense clouds, and electrical discharge. As a rule their approach are indicated by sultry weather and a falling barometer. These signs are followed by the usual ugly and threatening appearance of the weather, which forebodes most storms. The best and surest of all warnings, however, will be found in the barometer.
If the barometer falls rapidly, or even if the regularity of its diurnal variation be interrupted, danger may be apprehended.
And so the truth of the matter for squalls or cyclones.
It might have been that Captain Allen anticipated such a squall and which, theoretically, should have passed in a few hours. His suspicions might even have been confirmed when observing a dense, inky mass of low lying clouds on the western horizon.
In this case, however, it was a cyclone strengthening as it made landfall, Balla Balla.
7 December, 1908 a cyclone struck Broome, lasted for three days and caused widespread damage with the loss of 20 lives. 250 miles away at Port Hedland the following report reads like a prelude to 20 March, 1912:
Kalgoorlie Miner, 16 December, 1908.
ANXIETY AT PORT HEDLAND.
FEARS FOR THE STEAMER
SULTAN.
Port Hedland, Dec. 15.
The pearling disaster reported
from Wallal is causing considerable
anxiety here. The steamer Minnie,
well known in Port Hedland, in
charge of her owner (Harry
O'Grady), who had with him two
other white, men and a coloured
cook, left here for Broome, via
Condon, Wallal, and La Grange Bay,
on the 3rd inst., and was off Condon
the following Monday. This was
the day before the hurricane came,
since when no tidings of her have
been received.
Much anxiety is experienced here
concerning the fate of the steamer
Sultan, which left Port Hedland at
10 a.m. on the 8th inst. in the face
of a strong easterly gale, with a
falling barometer. She was almost
hidden by clouds of dust when
leaving the harbour. Port Hedland
was apparently on the edge of the
disturbance.
The morning of Tuesday,
the 8th inst., saw the sky overcast,
with heavy clouds. There was a
strong wind from the south-east,
which by 8 o'clock was from the
east, and at 11 o'clock from the
north-east. It was then almost
impossible for pedestrians to make
headway against it. At 6 p.m. the
wind had gone back to the east, and
lulled somewhat. The lowest
barometrical record was 29.28 deg.
at 5 p.m. on the 8th. This,
curiously enough, is identical
with the point reached by the
barometer at the Port Hedland
post office during the Wallal blow
last April. No damage was done
at Port Hedland. The rainfall
locally was 12 points (3mm)
It is extraordinarily similar to the pattern of 20 March and what's more the captain of the Sultan had no hesitation in putting to sea. This was clearly the approach to such conditions along the Nor'West coast!
 |
| SS Sultan - courtesy Flotilla Australia |
courtesy Google Earth; Hathi Trust, Australia Pilot, 1920, volume 4 and
http://fishing-app.gpsnauticalcharts.com/i-boating-fishing-web-app/fishing-marine-charts-navigation.html?title=Western+Australia+-+Solitary+Island+to+Bedout+Island+boating+app#11/-19.1354/119.4410
https://mooncalendar.astro-seek.com/moon-phases-calendar-april-2021
https://www.tide-forecast.com/locations/Port-Hedland-Australia/tides/latest#:~:text=The%20predicted%20tide%20times%20today,sunset%20is%20at%205%3A48pm.
https://www.tide-forecast.com/locations/Broome-Australia/tides/latest
Squall vs. Cyclone:
https://koombanarevisited.blogspot.com/2021/04/squalls.html
Projections for levels of water over the bar were made by correlating with present day data for both Port Hedland and Broome, April, 2021 - see links above. There is variability, but not significant enough to alter the overall pattern and challenges presented to Captain Allen.
