French beaches, best known for their topless female sunbathers, have been afflicted with a disgusting and deadly scourge: floods of green algae.
While this has been going on for nearly forty years, frequency and quantity have been increasing dramatically, and the last few years, the deadly green sludge has become a standard summer feature on TV (watch the video, France 2) and in the major dailies, such as Le Monde.
The latest victims were eighteen young wild boars, whose cadavers were found on July 26 along a one-kilometer stretch of beach on the English Channel in the Prefecture of Côtes-d’Armor (Bretagne). They were in addition to the ten cadavers found nearby the prior two days. Last year, a horse succumbed to the algae though the rider was able to get out. The year before, two dogs died that way.
They’d inhaled hydrogen sulfide, a colorless, foul-smelling, highly toxic gas that the thick algae sludge on the beach exudes once anaerobic decomposition sets in. Thankfully, as soon as this mess washes up, humans stay away from it because it’s disgusting and malodorous, but animals don’t necessarily get the message.
These algae have always been in the ocean and have not posed a problem until the late seventies. Spurred by massive subsidies from the French government and the EU (that is, Germany), fertilizer-intensive agriculture and industrial pig and dairy farms superseded the ancestral ways. And the main result, in addition to higher production, has been an enormous surface runoff of nitrates into the river system, estuaries, and the sea—350,000 metric tons (770 million pounds) last year in the Bretagne alone.
While French researchers estimate that 80,000 metric tons of nitrates is the maximum the Bretagne can discharge into the sea without causing algae blooms, national and local governments and industry groups have made no effort to curtail fertilizer usage and runoff. Instead, they focus on curing the symptoms: removing the algae sludge after it washes up on the beach.
Nearly 32,000 cubic meters (1.15 million cubic feet) of algae sludge were removed from Breton beaches in the first half of July, roughly 15% more than last year during the same period. For all of last year, 61,000 cubic meter (2.2 million cubic feet) were removed from 110 sites. Local authorities expect this year’s amount to be significantly higher. By comparison, only 27,000 cubic meter were removed in 2007.
This is dangerous work. The algae sludge has to be removed before anaerobic decomposition advances to where hydrogen sulfide levels become concentrated. Once that happens, people have to clear out. Meanwhile, beaches look like construction sites, and the tourist industry is complaining.
Then there is the conundrum of what to do with the sludge. Right now, they’re dumping it out of sight in woods and fields and remote locations, where it has to be air-dried—dangerous if anaerobic decomposition sets in. No one considers these fenced-in piles a solution. Meanwhile, researchers are working on converting the sludge into biodiesel and other fuels. It’s possible, but so far, it’s a very, very expensive fuel. À voir.
Recently, and ominously, algae blooms have started to wash up on beaches in the Normandy. But still, no effort is being made to deal with the cause. And in certain localities in the Bretagne, nitrates in drinking water are already double the maximum allowed by national regulations.
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