overshoot
‘Farmers are digging their own graves’: true cost of growing food in Spain’s arid south | Water | The Guardianhttps://www.theguardian.com/environment/2021/nov/16/farmers-are-digging-their-own-graves-true-cost-of-growing-food-in-spains-arid-southLas Tablas’ ecosystem relies on water from rainfall, the Guadiana river and a huge aquifer, but the climate crisis has resulted in Spain’s periods of drought getting longer. The Guadiana is drying up, while agriculture has depleted the aquifer and polluted the groundwater with phosphates and other chemical fertilisers. In 2009, the wetland was so dry that subterranean peat fires broke out.
The 3,000 hectares (7,400 acres) of Las Tablas are all that remain of what, according to the World Wildlife Fund, was once a system of 50,000 hectares of wetland in Castilla-La Mancha.
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Gosálvez says the water needed to irrigate Castilla-La Mancha’s vines, olives, pistachios, onions and melons exceeds available resources and short of a run of several years of heavy rain, the wetland can only be saved by transferring water from the Tagus river – except the Tagus is overexploited and almost dried up four years ago.
Much of the problem dates from the 1970s, when the Spanish government embarked on a plan to turn Murcia and Almería in the south-east into Europe’s market garden. The plan had one major flaw: there was no water.
Spain’s south-east is arid and none of the country’s three major rivers flows near it. The Douro and Tagus both rise in north-central Spain and flow west into the Atlantic at, respectively, Porto and Lisbon, while the Ebro rises in the north-west and empties into the Mediterranean nearly 400km (250 miles) north of Murcia.
The solution was to transfer water from the headwaters of the Tagus through almost 300km of pipeline to irrigate the barren south.
However, rather than satisfy demand, the transfer has served to incentivise unsustainable intensive agriculture that has led to the exploitation of groundwater, with disastrous environmental consequences.
The spectacle this summer of thousands of dead fish floating in the Mar Menor, a saltwater lagoon in Murcia once known for its crystal-clear waters, was the result of fertiliser polluting the groundwater that drains into the sea. The nitrates trigger vast algae blooms that deprive the fish of oxygen.
“The Mar Menor disaster is the result of intensive agriculture which continues to expand in a manner that isn’t sustainable, both in Murcia and in many other parts of Spain,” says Martínez-Fernández.
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Neighbouring Almería – where the greenhouses making up the famous “sea of plastic” are visible from space – produces an estimated 3.5m tonnes of peppers, tomatoes, cucumber and melons a year. Together with Granada, it supplies about 50% of the European market. Every year Almería also produces thousands of tonnes of plastic waste, much of which ends up in the sea.
The Tagus water transfer is not enough to meet the growing demands of agriculture in Almería, however. Over the past 40 years the amount of water that reaches the Tagus headwaters has fallen by about 40% according to estimates, and is continuing to fall. So Almería is increasingly reliant on desalinated seawater for irrigation.
In an attempt to deal with the problem, in 1985 the Spanish government brought in a new water law to regulate its use. But it was forced to concede that anyone who had a well or access to water had the right to exploit it.
Today, the government recognises that the situation is unsustainable. Teresa Ribera, minister for ecological transition, is under pressure for Spain to conform to European standards on water quality and quantity that come into force in 2027, and knows this can only be achieved by reducing irrigation.
In presenting the country’s five-year water plan, Ribera recognised that water resources are in decline and parts of Spain face desertification.