Wildfire risk rises as heat drives up drought pressure across the Netherlands

With sunny and warm weather expected in the coming days, the precipitation deficit is set to rise sharply. Weeronline says that the heat will cause a large amount of moisture to evaporate. An elevated wildfire risk is currently in place in 7 of the Netherlands’ 25 safety regions, according to a fire service risk map. All safety regions in Noord-Holland are included in the warning. In addition, two regions in Zuid-Holland and one in Limburg are operating under phase 2 conditions.

The opening weeks of June have been particularly wet in many places, although some areas, including parts of North Limburg, West Brabant, Zeeland, Noord-Holland, and the Wadden Islands, have seen less rainfall.

“There is no drought in these areas, but with the hot and sunny weather ahead, a lot of water will evaporate.” A precipitation deficit occurs when more water evaporates from the soil than falls as rain. On very warm days, the deficit can increase by 4 to 5 millimetres due to evaporation.

The current average precipitation deficit stands at 121 millimetres. That is close to the usual end-of-June deficit of 100 millimetres. The weather agency expects the deficit to rise to an average of 170 millimetres over the next 15 days. “With this precipitation deficit, we are once again approaching the 5% driest years since measurements began.”

The fire service activates phase 2 during extended dry periods in natural areas. Landowners, nature managers, and emergency services are urged to be extra alert because of the increased risk of wildfires and are asked to help prevent or contain any outbreaks. In the other 18 safety regions, phase 1 remains in place, meaning no additional precautions are currently required.

In late May, most safety regions were placed under an elevated wildfire risk due to warm and dry conditions. The Ministry of Defense subsequently suspended training exercises involving open fire, pyrotechnics, and explosives in natural areas.

This followed incidents in late April, when military exercises under similar conditions led to wildfires in Gelderland and Noord-Brabant. As weather conditions improved and became more humid during May, the risk level in most regions was reduced back to phase 1.

As code orange for extreme heat approaches, water authorities have introduced a range of measures. In the western Netherlands, water boards are supplying fresh water to counter salinisation, where rising salt levels threaten water quality. They are also stepping up inspections of dikes to monitor potential damage caused by drought and high temperatures.

“Peat dikes are particularly sensitive to drought,” said a spokesperson for the umbrella organisation of 21 water boards. “The general picture is that drought measures are in place everywhere, but we do see clear regional differences. The water boards in the west are supplying fresh water to prevent saltwater from moving inland. In areas where water cannot be supplied from the IJsselmeer, we see nature drying out quickly. In Noord-Brabant, several water boards have introduced abstraction bans.”

Starting this weekend, the likelihood of showers, including thunderstorms, will rise again.