Water Resource Availability at Very Low Flows (Q95)

The Environment Agency monitors water resource availability as part of the Catchment Abstraction Management Strategy (CAMS). A technical assessment is carried out to determine the water available in each river catchment. This is compared to the Environmental Flow Indicator (EFI) - minimum amount of water required to achieve healthy ecological status - in order to identify where resources demands from industry, agriculture or public water supply are compromising water quality and availability. This data is not raw, factual or measured. It comprises of estimated or modelled results showing expected outcomes based on the data available, and may not reflect local pressures. It was published in May 2026 here. Water resource availability at different flow levels can be investigated in detail: ■ Green = there is more water available than is required to meets the needs of the environment. ■ Yellow = if all licensed abstractions are carried out in full, there is not enough water to support the environment. ■ Red = flows are below the EFI and there is not enough water to support good ecological status. ■Grey= Heaviliy modified waterbodies, infludence by reservoir compensation release or augmented flows. The availability of water resources are based on the worst donwstream water body at the following flow percentiles: High flows (Q30): flow is only exceeded 30% of the time Moderate flows (Q50): flow is exceeded 50% of the time Low flows (Q70): flow is exceeded 70% of the time Very low flows (Q95): flow is exceeded 95% of the time This layer shows the Q95 very low flow scenario.