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Flow-through dam for flood control
Flow-through Dam for Flood Control Instruction
Flow-through dams (also known as perforated dams) are constructed solely for the purpose of flood control and mitigation of flood risks in downstream communities and ecosystems. Unlike reservoir dams, which are at built primarily for water storage or power generation, the spillway (opening) is built at the same height as the riverbed level, allowing the river to continue its natural flow in normal conditions. When water levels rise above the spillway, the dam restricts the amount flowing through the opening, decreasing peak flood flow. Since flow-through dams minimally affect rivers natural flows, under normal conditions negative environmental and socioeconomic impacts, such as sediment accumulation, restriction of water flow to downstream communities and ecosystems, and breaching during very extreme flood events, can be minimized or avoided altogether.
https://www.ctc-n.org/technologies/flow-through-dam-flood-control