Hameln barrage

The Hameln barrage in the town of Hamelin is the only barrage in the Upper Weser. It consists of fixed weirs, the upper weir and the lower weir. Since 1733, there has been a lock for shipping at the river island, which lies between the Upper and Lower Weir, which is now under the responsibility of the Weser Waterways and Shipping Authority. The slope of the barrage has been used by Hameln watermills since the 15th century. Even today, Stadtwerke Hameln operates the Alte Schleuse and Pfortmühle hydroelectric power plants here for energy generation. About 12 million kWh of energy, which corresponds to five percent of the demand in Hamelin, are produced annually by these hydroelectric power plants. The operators are only allowed to divert a maximum of 112 m³/s of Weser water or so much for the power plants that the Upper Weir does not dry up.

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