Lack of snow condemns Italy’s Po to a desperately dry summer
Italy’s largest river, is already as low as it was last summer, but this year the snowfields and the Alpine lakes that should save the Po River from drying up in the hot summer season have receded by 70%. (April 24) (AP video/Paolo Santalucia)
TRENTO, Italy (AP) — Italy’s largest river is already as low as it was last summer, with the winter snow fields that normally save it from drying up over the warmer months having receded by 75%, according to the Bolzano climate and environment agency.
It’s already causing some reliant on the Po to course correct.
“In a few days I will have to cancel all bookings for our Po River cruises because of the shallow water,” said captain Giuliano Landini as he shook his head, his arms stretched wide on the command deck of the Stradivari ship docked under the Boretto bridge and surrounded by long stretches of sand.
His 60-meter (196-foot) long vessel used to transport up to 400 people even on shallow waters, but the flow rate of the river is just 350 cubic meters (92,000 gallons) per second, as low as last June, when conditions were some of the hottest and driest in 70 years.
Navigation will soon become impossible if abundant rainfall doesn’t arrive soon.
The 652-kilometer (405-mile) Po River — which runs from the northwestern city of Turin to Venice on the eastern coast —traverses Italy’s most densely populated, highly industrialized and most intensively farmed part of the country, known as the Italian food valley.
It’s home to fishers and boats, feeds rich farmlands, powers turbines and quenches local populations across its banks and delta. The water also maintains tourism, with world-renowned lakes like Garda and Como crowded every year by millions of international vacationers who love to enjoy fresh clear waters, art and good food. Those who rely on it have often conflicting priorities and are having to scramble for alternative, water-saving plans.
Landini learnt how to swim and steer a boat on the Po river when he was a child.
“I was born on the river, it used to be so alive, full of fishermen and now in a few years we risk having only a sand motorway, I feel sick and anguish seeing the river in such a state,” he said looking at the rivers sandy banks getting closer and closer to his ship.
At the beginning of April, the river level hit a seasonal record 30-year low, with flow rates of one third of the seasonal average, according to the Po basin authority. The surrounding Alps experienced an unusually dry and warm winter so don’t have the snow reserves that would have normally fed the Po and various other tributaries in southern and western Europe in late spring and summer to meet the high water demand for irrigation, drinking and power generation.
Among the once heavily snow-covered peaks are natural and artificial lakes that are already 30% below seasonal average levels, with snow cover 75% below the 10-year seasonal average, explained Flavio Ruffini, director of the Bolzano province climate and environment agency.
The Alpine lakes in the province of Bolzano on average store about 100 million liters (26 million gallons) of water, but the current level is barely reaching 42 million liters (11 million gallons) after the dry winter. Alpine lakes are essential for the summer survival of Italy’s rivers.
The lakes are so parched an old tower is resurfacing from the bed of the artificial Vernago lake, while the ancient bell tower of the now-submerged village of Curon Venosta stands taller than usual in Resia lake.
Along the banks of the Adige river in northern Trento, the water also has a flow rate half the seasonal average.
The low flows let the Adriatic sea seep up the Po and Adige rivers for tens of kilometers (miles), endangering crops, clam farms, aquifers and even the drinking water of some villages.
Human-caused climate change is partially responsible: warmer temperatures melt snow and more water is evaporating into the air. It can make the droughts longer, more intense and more frequent.
The Italian government hasn’t yet appointed the extraordinary commissioner to mediate between the downstream and upstream regions and between citizens who pay for drinking water, agriculture, hydroelectricity, and tourism.
Local and national authorities will soon be faced with draconian decisions on possible water rationing and how to avoid water wars among various Italian regions if rain doesn’t fall soon.
“Italy is very good at handling emergencies, but quite bad in planning”, explained Alessandro Bratti, secretary general of the Po river authority. “In the recent drought decree issued by the government there is nothing, there is no multi-year planning, there are no executive infrastructure projects.”
Salted water intrusion could be curbed by anti-salt barriers, but the Po basin authority has only recently received the funds for a project on the Pila branch of the delta and it will take years or even decades before the foundation stone will be laid.
But Italian farmers aren’t waiting for an official response to the dry conditions. Many are investing in precision irrigation to save water during the hottest months of the year.
Probes that monitor the sap directly in tree trunks, drones that record the amount of water in the leaves, flying and underground drip irrigators and mobile applications are bringing water savings of up to 70% in some cases compared to the more wasteful sprinkler irrigation method.
“Trees go on standby when it’s too hot, no matter how much water you pour on them,” said farmer Monica Gilli. She recalled last year’s struggle to keep the field of pears alive and productive at the Pascolone farm near Bologna, when the temperature frequently exceeded 40 degrees Celsius (104 Fahrenheit) and did not give them any relief, even at night.
The Pascolone farm is now using drip irrigation methods that trickle water at lower rates and the help of Irriframe, a public and free internet portal that analyzes weather data, underground humidity probes and aquifers levels, giving exact indications on where, when and how much water needs to be poured on the fields.
“With technology and internet, we have halved our water needs”, said Simone Cocchi, owner of the Pascolone farm, “but we have also achieved the goal of not stressing nor overwatering the plants. The only problem is that those tools are very expensive.”
While the Irriframe software is free, the sensors are not.
The most expensive tool they use are the sap sensors that measure its flow, costing approximately 50 euros ($55) per probe. While drip irrigation is cheaper, installing it along a row of 250 trees can cost up to 1000 euros ($1,100), not including labor costs.
Still, the Acqua Campus research center estimates that 72% of the Emilia Romagna farmers are subscribed to the Irriframe open portal, meaning that 185,000 hectares out of a total 257,000 irrigated hectares in the region are watered using precision irrigation data.
In Italy, 16 regions are using the weather, humidity, and satellite data of Irriframe, a total of 7 million hectares of irrigated land.
But for all the farmers’ water-saving improvements, the region is still set to struggle if the rain doesn’t come.
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