Maelstrom in Saltstraumen

Can you imagine what 13 billion cubic feet of water rushing through an impossibly narrow, 500-foot-wide channel would look like? I couldn’t fathom it, but I was about to find out.

During our family vacation on the Hurtigruten Cruise in Norway, we signed up for the “Saltstraumen Safari” near the city of Bodø. This excursion promised to take us to Saltstraumen, the sound that connects the Saltfjord on the west and the much larger Skjerstadfjord on the east. When the tide tries to fill the Skjerstadfjord, up to 400 million cubic meters of seawater surges through the strait that is only 3 kilometers long and 150 meters wide.

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Our guide carefully checked to make sure we were all properly dressed in our fashion-forward waterproof gear and helped us into the inflatable rubber raft.

To the passengers’ squealing delight, our boat driver opened up the engine full throttle as soon as we cleared the speed limit zone near the docks.

On the Norwegian Sea side of the buoys, the water was still quite calm...

...but minutes later, we saw that the rock formations along the banks of the fjord bore clues to their turbulent past.

As the channel narrowed, the teal blue water became more restless.

Four times daily, the current can gain speeds up to 22 knots (~40 km/hr or ~25 mph), making this the strongest tidal current in the world.

The topography creates powerful whirlpools also called Maelstroms.

We passed through when the current was turning and the water was deemed "navigable". During the peak, the vortices of the whirlpools can reach 10 meters (~30 ft) in diameter and 5 meters (~15 ft) in depth. The force of these maelstroms are capable of eroding holes in the rock bed that are over 40 meters (~130 ft) deep.

We all gasped when our guide told us that extreme scuba diving is a popular sport here.

It seemed contradictory to see the bucolic scenery along the banks, with hikers enjoying the delicate wildflowers and sidestepping roosting waterfowl.

I was actively concerned for the safety of this black cow who looked like she could loose her footing on the slippery rocks at any moment.

We saw many fishing boats with motors fit enough to get them out of most any maelstrom jams.

I know nothing of fishing but it looks like this boat is equipped with every kind of fishing rod imaginable, or are they backup rods in case they loose a battle in the vortex?

We even saw one angler catch a fish, but they deemed it too small and tossed it back into the maelstrom. Anglers most commonly catch saithe and cod, but they can also expect to catch catfish, rose fish, trout, herring and halibut. Coalfish is the specialty of this area.

BTW, if you look closely, you can see that this small boat is powered by a 400 horsepower engine (!).

Then it was time to jet back because the tide was gaining strength.

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UPDATE: Thanks to Cuban in London, I have found the riveting short story by Edgar Allan Poe "A Descent into the Maelstrom" (1841). Here is an excerpt:

In a few minutes more, there came over the scene another radical alteration. The general surface grew somewhat more smooth, and the whirlpools, one by one, disappeared, while prodigious streaks of foam became apparent where none had been seen before. These streaks, at length, spreading out to a great distance, and entering into combination, took unto themselves the gyratory motion of the subsided vortices, and seemed to form the germ of another more vast. Suddenly --very suddenly --this assumed a distinct and definite existence, in a circle of more than half a mile in diameter. The edge of the whirl was represented by a broad belt of gleaming spray; but no particle of this slipped into the mouth of the terrific funnel, whose interior, as far as the eye could fathom it, was a smooth, shining, and jet-black wall of water, inclined to the horizon at an angle of some forty-five degrees, speeding dizzily round and round with a swaying and sweltering motion, and sending forth to the winds an appalling voice, half shriek, half roar, such as not even the mighty cataract of Niagara ever lifts up in its agony to Heaven.

The full story is here.

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UPDATE: November 4, 2014.

One of the photos in this Flickr set was posted by tahoe_miner_174  on reddit, which inspired a spirited geological discussion here, It included a depiction, by mjackl, of the four major deformation events:

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I will close with two videos. The first gives a brief look at the maelstrom in action.

This second video was taken by some brave divers.