The lake was created by inflowing groundwater after lignite mining in a planned open-cast mine. The recultivation operation plan of the then Rheinbraun, approved by the Brühl Mining Authority on October 3, 1959, was essentially based on preparatory work by the independent Cologne landscape architect Victor Calles, who had been doing this since 1946 for the recultivation of the mining areas in general and then in 1961 on behalf of the municipality on a specific plan for the area of the field in the middle of the community. The area is now under landscape protection, under the jurisdiction of the Rhineland Nature Park. [4] The remaining hole was originally divided by three clay ridges that were removed in order to join the individual areas into a large lake. At the same time, a sandy beach was laid out on the northwest side of the bank. [5] The area of the Otto-Maigler-See is 30 m higher than the surrounding area. A three-row forest protection planting around the lake protects the agriculturally used surrounding area from the increased wind effect of the west and south-west winds (wind damage). The tree plantings also extend over the top edge of the slope. In addition, the edges of the dump were leveled and strengthened through forestry recultivation. They were designed with heels (berms) in such a way that they can be used as paths and blend in harmoniously with the surroundings. [6]