In 1932 a dam was constructed on the Strymonas (or Struma) River, next to the village of Lithotopos. Since the dam retains the waters of the Strymonas River, this resulted in the construction of the artificial Lake Kerkini. In 1982, it became necessary to construct a new dam, since sediment from the river had reduced the capacity of the lake. The dam has seven large doors which open and close depending on the level of the lake and irrigation needs on the plain of Serres. The dam allows water to be propelled into the adjacent irrigation canal.