The low-flow period of a river corresponds to the lowest water levels, normally during dry periods. Low-flow support from dams consists of adding a supplementary flow to the naturally insufficient river flow, obtained by releasing water from the dam reservoir.
This flow, beyond the strict minimum reserved flow, regulates flow rates throughout the year and improves the environmental quality downstream of the dam by maintaining the proper functioning of aquatic ecosystems. It enables water resource management at the river basin scale. Indeed, the additional water thus released can then be used downstream through withdrawals from the river (for irrigation, to supply drinking water networks, etc.)
For example, the Naussac (43) and Villerest (42) dams regulate the flow of the Loire river with a water contribution, generally from June to September. Without these dams, the natural flow of the Loire at Gien (45) would have been only 10 m