From all I could gather, whilst there and since, folk (other than the resident population) come to Derby for one or both of two reasons.....they are about to travel the Gibb River Road (or have just come off it) or are here to see the incredible local tidal movement. And what tides they are, the largest in Australia, with the king or 'macro' tides making up to just under 12 metres.
But before we take a closer look at this extraordinary natural phenomenon, a bit about Derby itself. Derby is built on a strip of high ground which protrudes out into King Sound near the mouth of the Fitzroy River.
In this 'Landsat' photo of the Sound, this peninsula is the lower and smaller of the two on the right hand side of the photo. The Fitzroy River mouth is at the bottom of the shot, and its muddy waters show here in complete contrast to the normal blue of the sea further out in the Sound.
With a population of just under 5,000, the majority of whom are indigenous, Derby is one of only three towns in the Kimberly region (along with Broome and Kununurra) to boast more than 2,000 residents. This is remote territory indeed and certainly unlike anything we had experienced along the northern WA coast to date.
Derby was the first town to be established in the Kimberly (it was gazetted in 1883) and, consistent with the times, was named after a prominent Englishman, no less a personage than Lord Derby, the British Colonial Secretary of State between 1882 and 1885.
Derby has always been remote. In fact, in 1921, when it became the destination of the first scheduled air service from Perth, this route was the longest of its kind in the world, and remained so for some years. Not surprisingly, Derby has played an important role with the Flying Doctor Service and is still the base for the Kimberly School of the Air.
The remote location of the town contributed to the establishment of another facility altogether, the Derby Leprosarium, which housed the unfortunates suffering from this dreadful affliction between the 1920's and 60's. This was one of two such establishments in WA which contributed in no small way to the containment and eventual eradication of the disease. Who would have thought of that 'disease of the ancient and third worlds' being so prevalent here in Australia so recently? Certainly not your scribe.
When Derby was established, the Kimberly was being opened for sheep grazing and wool production. Transport overland to the southern markets of Perth and beyond was totally impractical in those days and the now famous Derby wharf was built to allow for export by sea.
This aerial shot, courtesy of 'derbytourism', shows the odd semicircular design which is the current wharf structure. This was not always the case. This is a wharf of two distinct parts.
The remote location of the town contributed to the establishment of another facility altogether, the Derby Leprosarium, which housed the unfortunates suffering from this dreadful affliction between the 1920's and 60's. This was one of two such establishments in WA which contributed in no small way to the containment and eventual eradication of the disease. Who would have thought of that 'disease of the ancient and third worlds' being so prevalent here in Australia so recently? Certainly not your scribe.
When Derby was established, the Kimberly was being opened for sheep grazing and wool production. Transport overland to the southern markets of Perth and beyond was totally impractical in those days and the now famous Derby wharf was built to allow for export by sea.
This aerial shot, courtesy of 'derbytourism', shows the odd semicircular design which is the current wharf structure. This was not always the case. This is a wharf of two distinct parts.
In 1894 the first, timber construction was limited to a 'T' shaped pier extending from the shore along the straight length of jetty seen here on the right side of this photo. A horse drawn tram traversed the low lying flats between the wharf and the main township and exports in those days were primarily wool and pearl shell.
Sheep are not ideally suited to the Kimberly. They were gradually replaced by cattle, and many years after the first wharf was built, in 1964 in fact, the curved, cement structure was added to the existing Derby wharf. Live cattle was by now the major export.
In 1994, with a downturn of passenger services by sea to Derby and of exports generally, the Department of Transport closed the wharf, only to re-open it in 1997 (after some pretty hectic local agitation) to facilitate the export by barge (this is anything but a deep sea facility!) of lead and zinc concentrate from the Cadjebut mine near Fitzroy Crossing.
Whilst these exports continue, the Derby wharf is now predominately used by those chasing fish and mud crabs and others like us who come here to stare in stunned amazement at the phenomenon which is the Derby tide.
Just as the trams of old did, we made our way out from the end of Loch Street (which runs through the heart of the town)
and onto Jetty Road which crosses the tidal mud flats surrounding the township on both sides.
The jetty precinct is a kilometre or so north-west of the end of the main town where an old crane and a warehouse mark the entry point.
Here too, these old cattle ramps and race rails stand as a reminder of days gone by (with the building of the wharf cafe...very good fish and chips... at the end of the roadway)
Two visits to this precinct are essential,,,,,one on the bottom of the low and again at high tide. We were lucky. During the two days of our Derby visit the moon was full and the tidal movement was significant.
Hopefully this series of comparative photos will give you some idea of just what an incredible movement of water takes place here on a daily basis. But why is this so? Two natural features of the coastline near Derby combine to produce this end result.
As the bulge of water produced by the tidal pull of the moon approaches from the depths of the Indian Ocean, the shallow continental shelf which extends out from the coast forces it upwards. When this mass of water, which is already beginning to move quickly, is then squeezed between the comparatively narrow and ever shallower confines of King Sound, the race is on! This huge mass of seawater can only go upwards, and at speed, as it travels up the Sound. The 'macro' tides of Derby are born.
The results are spectacular. There are only five other places in the world with tides like these. The Bay of Fundy in Canada claims the prize with 15 metre tides, but Derby's were good enough for me!
At the bottom of the low, the wharf rises starkly from the mud flats on which it is built.
Six or so hours later....can this possibly be the same place?
This is the original part of the wharf
where, of course exactly the same thing occurs.
As the tide fills, the mangrove studded, muddy shoreline of low tide
disappears completely.
No matter from what angle along the wharf one takes these shots
the result is the same.
Apart from the enormous volume of muddy water which ebbs and flows, the speed with which it does so is phenomenal.
As the shadow of yours truly at the rail of the wharf shows, I took this shot in the late afternoon looking down on the incredible swirls and eddies in the wharf basin as the tide hooted in
Every obstruction in the way of this rushing brown torrent produces ever changing patterns on the surface.
The one thing which I cannot reproduce here in any form is the noise.......a constant hissing and slopping sound accompanies each of these tidal movements, both on the flow and the ebb. I shudder to think what would happen to anyone who fell in. At a rough estimate this tide was flowing at a good five knots.
I have to admit I had not been prepared for the colour of the water. This is a constant here in Derby......there is no such thing as blue water in the wharf precinct, nor for that matter, anywhere as far as could be seen in the expanses of water in the estuary channels.
The mighty Fitzroy River (and it is, as we learnt later) continually dumps the silt of its passage through its catchment into this end of King Sound. The movement of the water here is so great that it never gets the chance to settle to the bottom....the waters of Derby remain a constant giant chocolate milkshake! The extent to which this muddy sediment stains the Sound can be clearly seen in the satellite photo above.
If there have been occasions on which my preconceived expectations of something we were about to see have been less than met, this was not one of them. The tides of Derby are one of the most impressive things I have ever seen. I could have happily revisited time and time again just to marvel. But we did take the time to look a little further around this outback town, something I'll share with you in my next.
Sheep are not ideally suited to the Kimberly. They were gradually replaced by cattle, and many years after the first wharf was built, in 1964 in fact, the curved, cement structure was added to the existing Derby wharf. Live cattle was by now the major export.
In 1994, with a downturn of passenger services by sea to Derby and of exports generally, the Department of Transport closed the wharf, only to re-open it in 1997 (after some pretty hectic local agitation) to facilitate the export by barge (this is anything but a deep sea facility!) of lead and zinc concentrate from the Cadjebut mine near Fitzroy Crossing.
Whilst these exports continue, the Derby wharf is now predominately used by those chasing fish and mud crabs and others like us who come here to stare in stunned amazement at the phenomenon which is the Derby tide.
Just as the trams of old did, we made our way out from the end of Loch Street (which runs through the heart of the town)
and onto Jetty Road which crosses the tidal mud flats surrounding the township on both sides.
The jetty precinct is a kilometre or so north-west of the end of the main town where an old crane and a warehouse mark the entry point.
Here too, these old cattle ramps and race rails stand as a reminder of days gone by (with the building of the wharf cafe...very good fish and chips... at the end of the roadway)
Two visits to this precinct are essential,,,,,one on the bottom of the low and again at high tide. We were lucky. During the two days of our Derby visit the moon was full and the tidal movement was significant.
Hopefully this series of comparative photos will give you some idea of just what an incredible movement of water takes place here on a daily basis. But why is this so? Two natural features of the coastline near Derby combine to produce this end result.
As the bulge of water produced by the tidal pull of the moon approaches from the depths of the Indian Ocean, the shallow continental shelf which extends out from the coast forces it upwards. When this mass of water, which is already beginning to move quickly, is then squeezed between the comparatively narrow and ever shallower confines of King Sound, the race is on! This huge mass of seawater can only go upwards, and at speed, as it travels up the Sound. The 'macro' tides of Derby are born.
The results are spectacular. There are only five other places in the world with tides like these. The Bay of Fundy in Canada claims the prize with 15 metre tides, but Derby's were good enough for me!
At the bottom of the low, the wharf rises starkly from the mud flats on which it is built.
Six or so hours later....can this possibly be the same place?
This is the original part of the wharf
where, of course exactly the same thing occurs.
As the tide fills, the mangrove studded, muddy shoreline of low tide
disappears completely.
No matter from what angle along the wharf one takes these shots
the result is the same.
Apart from the enormous volume of muddy water which ebbs and flows, the speed with which it does so is phenomenal.
As the shadow of yours truly at the rail of the wharf shows, I took this shot in the late afternoon looking down on the incredible swirls and eddies in the wharf basin as the tide hooted in
Every obstruction in the way of this rushing brown torrent produces ever changing patterns on the surface.
The one thing which I cannot reproduce here in any form is the noise.......a constant hissing and slopping sound accompanies each of these tidal movements, both on the flow and the ebb. I shudder to think what would happen to anyone who fell in. At a rough estimate this tide was flowing at a good five knots.
I have to admit I had not been prepared for the colour of the water. This is a constant here in Derby......there is no such thing as blue water in the wharf precinct, nor for that matter, anywhere as far as could be seen in the expanses of water in the estuary channels.
The mighty Fitzroy River (and it is, as we learnt later) continually dumps the silt of its passage through its catchment into this end of King Sound. The movement of the water here is so great that it never gets the chance to settle to the bottom....the waters of Derby remain a constant giant chocolate milkshake! The extent to which this muddy sediment stains the Sound can be clearly seen in the satellite photo above.
If there have been occasions on which my preconceived expectations of something we were about to see have been less than met, this was not one of them. The tides of Derby are one of the most impressive things I have ever seen. I could have happily revisited time and time again just to marvel. But we did take the time to look a little further around this outback town, something I'll share with you in my next.
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