In Sambs v. City of Brookfield, 66 Wis. 2d 296, 306, 224 N.W.2d 582 (1975), the City of Brookfield had created a set of ditches and culverts which were designed to divert runoff from melting snow away from the road. It turned out that the culverts were inadequate to handle the flow of water from a normal thaw. Sambs, 66 Wis. 2d at 301-02. As a result, the culverts became blocked by ice, preventing water from going under the road instead of onto it. This blockage had occurred on numerous occasions. Thus, in Sambs, the defective drainage system, which the municipality had created and maintained, contributed to the creation of the hazard.