Measuring water height (m) and discharge rate (m³/s)
Automated sensors along bridges and riverbanks continuously measure free water surface height. A station-specific rating curve converts height into discharge volume per second.
フランス・インスタント天気 — Instant Weather › Rivers & Floods
The Rivers & Floods page tracks water levels across major French rivers, tributaries and mountain streams, displaying measured water height in meters, estimated discharge (m³/s) and real-time trends.
Automated sensors along bridges and riverbanks continuously measure free water surface height. A station-specific rating curve converts height into discharge volume per second.
Large lowland rivers (Seine, Loire, Garonne, Rhône) respond gradually over several days, whereas steep Mediterranean and mountain catchments can rise by several meters in under two hours during stationary storms.
Each hydrological sheet recalls water levels reached during major past floods to contextualize current river rises against bankfull thresholds.
Runoff collected across upstream hills and tributaries takes hours or days to travel downstream: this is the flood wave propagation time.
Never drive or walk onto a flooded road (30 cm of moving water can sweep a car away), stay out of underground garages and move to higher floors.
Low-water flow refers to the lowest average water level reached by a river during the year, typically at the end of summer.