Breached dam near Maastricht threatens 30 houseboats; Homes evacuated

A breach in a spillway dam in Maastricht on Wednesday led to the evacuation of about 30 houseboats. The situation was first reported at 3:15 p.m., and was being treated as a local disaster response by emergency services workers.

Spillways are used to adjust water flow by lowering them at a dam so water only flows away at higher levels. The affected spillway is near the Bosscherveld water lock off Stuwweg on the north side of Maastricht. It is managed by infrastructure agency Rijkswaterstaat.

"Part of the spillway lining was loosened by the force of the water and washed away," said the Zuid-Limburg emergency services office. When a breach happened, the water level falls quite quickly. "There are a number of houseboats directly in front of the spillway. It is important for residents that the water level does not fall too low, so as not to become crooked."

The 30 houseboats were evacuated as a precaution. "We are investigating what recovery measures need to be taken," said the Rijkswaterstaat district office for the southern region of the Netherlands. The spillway is 120 meters wide, and the breach expanded to a width of about 50 meters as the water began to rush through the gap.

The alarm was initially raised to a Grip 1 regional emergency, where all first responders answer to a single incident command at the scene. It was later scaled up to a Grip 2 emergency. This protocol requires the establishment of a Regional Operational Team to work from a central location to provide advise, coordinate the response, and assist in collecting and distributing information. The crisis management protocol was still in place at 7 p.m.

Earlier in the day, the infrastructure agency said they planned to lower the weirs to allow water to flow faster from the Maas River to the sea. Though the location of the breached spillway is relatively close to the Borgharen weir, Rijkswaterstaat said the damaged spillway was not caused by the increased flow of water. The river's outflow was at a rate typically seen only once per year, at over 1,620 cubic meters per second.

The Maas River near Maastricht will continue to see the water level rise as rainfall in the Ardennes reaches the southern Netherlands. The river should reach its high point around 10 a.m. on Thursday.