Drought

Unrelenting drought in the Po basin: pre-Alpine lakes almost dry

The Po District Observatory has confirmed that the water stress level remains ‘high’. Lake Maggiore is experiencing extreme drought, the flow rates of the River Po remain well below historical averages, and the salt wedge continues to advance up the Delta

10 August 2026

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3' min read

Translated by AI

Versione italiana

3' min read

Translated by AI

Versione italiana

The water crisis in the Po river basin shows no sign of easing. The Permanent Observatory on Water Use in the Po River District, which met on 6 August under the coordination of the District Basin Authority, confirmed a highly critical situation, characterised by persistently above-average temperatures, insufficient rainfall in the worst-affected areas and water levels in the major Alpine lakes now approaching historic lows.

Although there have been a number of thunderstorms in Emilia-Romagna and Veneto in recent weeks, the impact on water reserves has been limited. The rainfall has been concentrated in intense, localised downpours, which have been unable to make up for the deficit that had built up over previous months. In Piedmont and Lombardy, however, rainfall has generally remained below average.

PORTATA DEL PO

The situation regarding the large regulated lakes in northern Italia is of particular concern, as they represent a strategic reserve for agriculture and for maintaining the flow of the River Po. The most critical case is that of Lake Maggiore, whose water level has fallen to 5.3 per cent, a condition classified as ‘extreme drought’. Lake Como (5.9 per cent), Lake Iseo (5 per cent) and Lake Idro (5.7 per cent) are also in difficulty, whilst only Lake Garda remains relatively stable, with a water level of 50 per cent.

“The persistent high temperatures are putting a strain on the last remaining water reserves – namely the large pre-Alpine lakes. With the exception of Lake Garda, the water levels in Lakes Maggiore, Como and Idro are almost depleted,” explained Alessandro Delpiano, Secretary-General of the Po River Basin Authority. “The emergency continues and there is still no end in sight.”

The situation is particularly critical for the Ticino-Lake Maggiore system, which is vital for supplying Europe’s largest rice-growing region, comprising the provinces of Vercelli, Novara and the Lomellina. Right in the middle of the irrigation season, farms are having to cope with increasingly limited water supplies.

Even the great river continues to show signs of distress. Following a temporary rise in flow rates in the second half of July, discharge levels have once again begun to fall along the entire length of the Po, settling well below historical reference values. In Piacenza, the current flow rate is 177 cubic metres per second compared with a historical average of 497; in Cremona, 193 compared with 602; in Boretto, 209 compared with 581; and in Borgoforte, 219 compared with 645. Even more significant is the figure for Pontelagoscuro, near the mouth of the river, where the river is flowing at 246 cubic metres per second compared with a historical average of 709.

LIVELLO DEI LAGHI

The reduction in water flows continues to fuel the phenomenon of saltwater intrusion in the Po Delta. Seawater now penetrates more than 20–25 kilometres inland along the delta’s branches, with consequences for irrigation water abstraction and the most vulnerable ecosystems.

The critical issues affect various sectors. The irrigation sector – in particular rice farming in Piedmont – is among the hardest hit, but difficulties are also being reported in Lombardy and Veneto. At the same time, pressure on the drinking water supply is mounting, particularly in the hilly and mountainous areas of Piedmont and Lombardy, where measures to ensure the supply to local communities are being stepped up.

To maintain flow rates in the Po, the River Basin Authority and the regions have asked hydroelectric operators to release more water from the Alpine reservoirs. Some of the additional releases have already taken place, but the scope for action remains limited: the main national reservoirs are, in fact, only 38–40 per cent full. Also under consideration is the possibility of requesting further releases from the Swiss reservoirs in the Ticino-Lake Maggiore catchment area through the bilateral cooperation mechanism between Italia and Switzerland.

The weather forecast indicates that new weather systems will pass through over the coming days, bringing thunderstorms and a temporary drop in temperatures. However, according to experts, the effects are unlikely to be sufficient to bring about any substantial change to the overall picture.

For this reason, the Observatory has decided to maintain the ‘high’ water stress level for the entire Po District. This assessment reflects a situation in which extreme drought, reduced water reserves, difficulties for agriculture and water supply systems, and the advance of the salt wedge continue to pose a real threat to northern Italia.