Across Flanders, more water fell in one weekend than in an average entire month of November. Experts said the flooding was the worst in 50 years. In Wallonia's Hainaut province, three people in their 60s and 70s died due to the flood, and one committed suicide after hearing of the death of her partner.

In Antwerp, 40 municipalities were affected by flooding, according to provincial governor Cathy Berx. There was a risk of flooding at Mechelen, Lier, Ranst and Boechout, as heavy waters flowed from Wallonia and Flemish Brabant. The Antwerp authorities were keeping a close watch on the level of the River Zenne.

In Brussels, the provincial disaster plan was launched, as the canal broke its banks. Streets in the communes of Vorst, Ukkel, Watermaal-Bosvoorde and Drogenbos were flooded, and the city's fire service took more than 1,500 emergency calls on Saturday alone.

Brussels public works minister Brigitte Grouwels said: "My thoughts go in the first place to the people affected by water. This flooding is mainly a result of the enormous mass of water flowing from the tributaries of the Zenne in the south of Brussels. I want to thank the people who have worked day and night over recent days to stabilise the situation."

In East Flanders, schools in Ninove, Geraardsbergen and Brakel remained closed on Monday because of flooding. The Dender stood 46 centimetres above the alarm level, and the flow of water was estimated to be five times higher than normal. However, the province reported that cooperation with the emergency services had been "excellent". Homes were evacuated in Ninove and Geraardsbergen.

In Flemish Brabant, the railway line between Halle and Brussels was closed after the Brussels-Charleroi canal burst its banks. Houses in Beersel and Sint-Pieters-Leeuw were evacuated. The town of Herne was cut off entirely for a time, and fire services advised onlookers and the press to move away from the banks of the Brussels-Charleroi canal.

In Limburg, the Velp overflowed at Halen, and people were evacuated from their homes. A rest home was evacuated in Bree, and the roof of a store in Genk collapsed under the weight of water. No-one was injured, but material damage was extensive.

West Flanders was the least affected of all the provinces, with few call-outs in the coastal municipalities. Problems on Saturday in Kortrijk, Avelgem and Zwevegem were largely cleared up by Sunday, fire services said.

Despite the widespread damage and the enactment of disaster plans in several places, acting prime minister Yves Leterme said the federal disaster plan would not be put into operation, as that would only hold up emergency aid efforts. The government would be following the situation closely, he said, to consider if federal disaster aid was appropriate.

Federal interior minister Annemie Turtelboom said her department was fairly certain that the Royal Meteorological Institute would confirm that conditions would merit the use of the disaster aid fund, which compensates victims for damage.

Belgians affected by the floods were being advised to take photos and videos of damage. The insurance industry organisation assured homeowners that anyone with a fire insurance policy would automatically be covered for water damage. The province of East Flanders also advised homeowners to mark the level the water had reached and check walls and ceilings for structural damage.

According to weatherman Frank Deboosere of VRT television, the flooding was made worse by developed areas in Flanders on land that would otherwise serve as a natural escape route for rainwater. Instead of flowing into the ground, the water gathers. In addition, he explained, construction and agriculture have both shifted rivers and streams from their natural courses, making flooding more likely.

"This is clearly an extreme situation," commented environment minister Joke Schauvliege. While admitting that heavy rainfall had much to do with it, she noted that "too many building permits were given in the past for construction in overflow areas." On Monday, she joined Flemish public works minister Hilde Crevits and minister- president Kris Peeters to visit some of the hardest-hit locations along the Brussels-Charleroi canal.