The Disappearing Sand

The news that Muro and Can Picafort beaches have been losing approximately a thousand square metres of area every year sounds alarming to say the least. Or is it? I confess that being able to conceive of one thousand square metres is something of a challenge. Were it all in one place, then it would be pretty straightforward and far, far more alarming. One assumes, one knows, therefore, that the thousand square metres per annum have been rather more widely distributed or un-distributed, as the case may be.

The loss of this beach area has been going on for some time. Over fifty years, up to 2008, the beaches were divested of 51,000 square metres, which really is very much more alarming. One wonders, though, how it is that there still are beaches, and beaches, moreover, which look in a pretty reasonably sandy state.

One imagines that if one goes further back in time, i.e. longer than the 50-year period that they appear to have been measuring the loss of beach, there was also some loss. Or perhaps there wasn't.

The erosion is down to two things: the wind and a lack of sediment being washed up to replace the dispersed beach. It isn't, or isn't yet, the consequence of rising sea levels, but these are probably only a matter of time.

The wind has always been there and there isn't a great deal that can be done about it. Or rather, this was the case before the Costas Authority, now making a big deal about how it is saving the beaches, hit upon the idea of putting up sand traps. These, for the most part (and they are to be found on beaches elsewhere), are sort of bamboo/wicker affairs. Others are altogether more solid constructions, i.e. of wood, normally right at the back of beaches where the beaches meet roads. The theory behind the traps is simple enough. The sand is buffeted up against them rather than blown by the wind all over cars that have been parked on the adjoining roads.

I went and had a look at some of these sand traps. I could remember when they were originally being put up. The solid ones are still solid enough, but the others most certainly aren't. There does seem to be a major design flaw, as in they are too flimsy to withstand not the sand but the force of nature which drives the sand in the first place, namely the wind. Most of them are bent or broken or simply are no longer there. The Costas do a good job in saying what a good job they are doing in saving the beaches but do a less good job when it comes to maintenance.

The lack of sediment is potentially all the more troubling. Over the fifty years, the Costas reckon that only some 250 square metres have been deposited, which is negligible when compared with the overall erosion. Why would this be though? One answer may well lie with the posidonia sea grass.

It has been proved that posidonia traps sediment and prevents it suffering its own erosion. This, in turn, facilitates its being brought to shore, a naturally occurring phenomenon as the sea grass is broken down and then deposited onto beaches by wave motion. But if the posidonia is being lost (and it is argued that it is), then a replenishment with sediment is affected. At least I think this is how it's all meant to work. Perhaps there is a marine biologist out there who can offer a rather better explanation.

The drive to prevent a loss of beach started earlier than the installation of the sand traps. Five years ago, the dunes began to be roped off and at the same time somewhat peculiar notices began to appear asking beach users to brush sand off themselves as the sand was needed. It seemed a rather odd request, but now it seems rather less odd.

The roping-off of the dunes has gone way further. There is now one designated route through the dunes and forest where Playa de Muro and Can Picafort beaches meet. It is a real shame, as it used to be possible to just ramble wherever you wanted. Nature is now fenced off and has to be admired by looking on rather than being a part of.

Wind, sediment, beach users taking sand home on their towels. One can, I suppose, understand all this. But there is one further factor, and it applies especially to Can Picafort. Construction. Dunes were levelled and were built on. And when did this start? About fifty years ago.

Any comments to andrew@thealcudiaguide.com please.