Belgium’s Drought Crisis Deepens as Heatwave Strains Infrastructure
Belgium is grappling with one of its most severe drought summers on record, as an ongoing heatwave continues to strain the country’s infrastructure, agriculture, and emergency services. Trees are shedding leaves prematurely, Christmas tree growers face losses of up to 100 percent, a meadow fire broke out in West Flanders, and even cold water taps are running warm — while Walloon authorities have decided against introducing new measures despite the concerning situation.
A Summer of Extremes
The crisis is rooted in an exceptionally dry and hot summer. July 2026 saw just 10.6 millimeters of precipitation at Uccle — a mere 14 percent of the seasonal norm, according to RTBF. In Flanders, average precipitation across all measurement sites was just 3.9 millimeters. The result has been a rapid deterioration of groundwater reserves: 80 percent of Flemish groundwater stations now show low to very low levels, up from 50 percent in June. At 87 percent of stations, absolute levels are critically low — already exceeding the 2025 maximum of 82 percent.
The Royal Meteorological Institute (KMI) has issued a new heat code yellow for the entire country, in effect until midnight Thursday, with temperatures expected to reach 30 to 31 degrees Celsius this weekend, as VRT NWS reported. The ozone and heat plan warning phase of the Federal Public Service for Public Health remains active, and forecasters warn the drought index is intensifying from dry to very dry, trending toward extremely dry over the next ten days.
Trees Enter ‘Autumn Mode’ Prematurely
One of the most visible signs of the crisis is the sight of trees losing their leaves in the middle of summer. According to VRT NWS, the phenomenon is caused by drought stress that triggers a hydraulic failure known as an ‘embolism’ — air enters the water-carrying vessels of the tree instead of water, cutting off the supply to the leaves.
“An embolism has as a consequence that deciduous trees drop their leaves. As if it were autumn, although that is of course different from what happens in autumn,” explained Kathy Steppe, an ecophysiologist and bio-engineer at Ghent University (UGent), who monitors trees through the treewatch.net sensor network.
Steppe noted that conifers such as spruce and pine are struggling more with the heat than deciduous trees. Among broadleaf species, birch is the most drought-sensitive, followed by beech, plane tree, and oak. However, she cautioned against simply planting only the most drought-resistant species, noting that “species that are less adapted to heatwaves can generally transpire much more and therefore have a greater cooling capacity” — a crucial consideration for urban environments.
Christmas Tree Growers Face Devastating Losses
Belgium’s Christmas tree industry is among the hardest hit. Growers report losses ranging from 50 to 100 percent, according to VRT NWS. The situation is equally dire for producers in Wallonia, as RTBF detailed.
Thierry Vincent, a producer with more than 35 years in the sector, described the devastation on his plots: trees planted in April did not survive July’s heat and dry conditions. “It is completely dead. No kind of recovery. It will need to be replanted,” he said, adding that the soil is “hard as concrete.” On one plot alone, 1,300 trees will need to be removed and replanted.
Yves Pirothon, president of the Union ardennaise des Pépiniéristes, expects at least 10 percent losses, “but it can go up to 50%, even 100% depending on plots and regions.” Bertrand Pirothon, production manager at Pirothon nurseries, said replanting has been halted since early July because “it’s simply too dry and too hot.”
The full consequences may not be felt for five to seven years, when fewer Christmas trees could be available on the market and prices could rise.
Meadow Fire Highlights Fire Risk
Emergency services are also feeling the strain. Firefighters were called out Saturday evening to a meadow fire in Nieuwkerke (Heuvelland) in West Flanders, according to VRT NWS. The fire, likely sparked by an electric fence, spread over approximately 20 meters long and 3 meters wide before being contained. Dry grass and wooden fence posts allowed the blaze to spread quickly.
The landowner helped firefighters by bringing water with his manure tanker. “We were there fortunately quickly,” said Wim Bossaert of the fire brigade. “The farmer also came to our aid by bringing water with his manure tanker.”
Fire risk remains ‘moderate to high’ in both open and forested areas across Wallonia, according to the regional drought unit, despite a temporary decrease following rains on August 3.
When Cold Water Isn’t Cold
Even the simple act of turning on a cold water tap has become a reminder of the crisis. Many Belgians are finding that water labeled ‘cold’ comes out warm or lukewarm, as RTBF reported.
The cause lies in the intense heat warming water sources like the Meuse river — which supplies 30 percent of Brussels’ drinking water — as well as the soil surrounding pipes and poorly insulated household plumbing in overheated basements.
Eric Chauveheid, lab manager at Vivaqua, Brussels’ drinking water producer, said the company is responding by increasing chlorine doses and strengthening vigilance during hot periods. “We have very rigorous processes to control water, including microbiological analyses,” he said.
While tap water remains potable, Dr. Carole Schirvel of Cliniques universitaires St-Luc warned that bacteria like legionella can begin to reproduce above 25 degrees Celsius. “If one is in good health, even the consumption of warmer water will have no effect on health,” she noted, but recommended letting water run a few seconds before drinking and refrigerating water in a carafe.
Walloon Authorities Hold Steady
Despite the concerning situation, Walloon authorities decided at their weekly meeting on August 6 to introduce no new measures, as RTBF reported. The drought unit warned that “in the absence of rain in the coming weeks, the situation will become critical.”
Existing restrictions remain in force: fishing in fast-flowing and mixed waters is prohibited, kayak and leisure boat bans are extended across all Walloon stretches, and swimming remains banned at several lakes. Nine communes have water use restriction orders, with 14 more in the Nisramont dam area under surveillance. The next drought cell meeting is scheduled for Thursday.
What to Watch For
With the KMI drought index trending toward ‘extremely dry’ and no significant rainfall forecast, Belgium’s water crisis shows no signs of abating. Groundwater levels could exceed 90 percent at low levels if dry weather persists. The coming weeks will be critical for farmers, forest managers, and water utilities alike — and for the country’s iconic Christmas trees, the damage may already be done.