9 Feb 2018

49. Boxes, water and old men

The visible edge of a dike of grey basalt
cutting vertically up through different
layers of mostly porous rock. The brown
layer in the middle is possibly that colour
because it was burnt by a very hot lava
flow of basaltic material which formed
a fragmentary sill whose vertical prisms
are just visible to the left of the dike.
The Canary Islands are huge piles of volcanic rubble sticking out of the sea. Much of this rubble is made up of layers of porous rock on layers of hard impermeable rock, called 'sills', so that each island roughly resembles a many-storeyed wedding cake. As the cake consolidated it cracked and into these cracks lava was squeezed up from the magma below. This lava solidified into impermeable walls called 'dikes'. Inside the island, then, the dikes and sills together formed a stack of boxes with impermeable sides whose porous contents filled with water filtering down over millions of years from rain and snow on the surface. Consequently, at least in the western province, there are few vertical wells and the islands’ supply of ground water is extracted by horizontal wells, called galleries, that break through the walls of the boxes (the dikes) as they burrow at different levels into the sides of each island.

Unfortunately, in our island there are few effective sills and few boxes. The precipitation we receive simply leaches down and down into the heart of the island, then out into the sea. Traditionally there was no point in digging wells near the villages. Attempts to harness runoff in dams in the gullies proved useless because without modern materials the porous ground absorbed all the water. So the only water available to the islanders was the rainwater they collected in their domestic cisterns, a few minor springs and a natural lens of freshwater at Icota near El Pinar. And of course the Garoé.

In the middle of the twentieth century some enterprising islanders from La Palma tried to cultivate bananas in El Golfo. They finally gave up but they did leave us a part of the solution to the island’s water problem. Wells can be effective if they are cunningly located and designed. One such is the “Pozo de los Padrones” on the straight road through the badlands to Frontera, just after leaving the tunnel. There is a panel on the wall of the pump house explaining how the excavation begins as a well (pozo) going straight down and then continues as a horizontal gallery under the imposing 3,000 foot crag opposite.

A view of Frontera on a day of sunshine and drizzle in February. The mountains part-hidden by cloud capture the moisture from the Trade Winds and this water filters down through the rock. El Pozo de los Padrones is at the foot of the crag in the centre of the photo and burrows right into the heart of the mountain.

There is a tap at the pump house where the public can collect drinking water, pure unchlorinated “fossil” water. One day I was there with my collection of five-litre plastic bottles when four cars pulled up, each driven by a man of my age and, of course, we struck up conversation.

The pump house at Pozo de los Padrones. The relic on the
left painted white was the scoop at the head of excavations
when the gallery was being dug. The rubble was taken out
in gondolas like the one just behind it. The excavation must
have been backbreaking work for the men aided only by
dinamite and this minature machinery. A gallery is a very
confined space, perhaps little higher than a man and not
much wider than the skips on rails, the air stifling, damp
and hot.
While we waited our turns, the banter went something like this:

- “When I was a young man I used to go to the spring every day. Not to get water, mind you! But to chat up a certain young lady. Now she sends me here to get me out of her sight!”
- “That’s it! Things have changed. No girls here today, eh? All up at the tables in the Avenue. Showing themselves off. Drinking gin-tonics!”
- “Yep! All we’re good for is to fetch water, take the rubbish down, walk the bloody dog and mind the grandson when his parents are out!”
- "When I was young, old men were looked up to, respected. Now you’d think we’re in the way! And that's if they see you!”
- “Nonsense! We old men are the greatest.”
- “How come?”
- “The greatest. The biggest thing today. We don’t fit in anywhere!”

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