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.