The River Test
This graph shows recent flow data for the River Test during 2024–25. (Source: The Environment Agency)
River levels
View the current water levels of the Rivers Test and the Itchen and find out how flow triggers work and what happens when we're at risk of a drought in Hampshire and on the Isle of Wight.
Water supply
In some areas, like in Hampshire and on the Isle of Wight, we rely on rivers for the water we supply to our customers. More recently, the pressures of more extreme weather events and a growing population are stretching these precious resources.
Further information on river flows can be found on the EA Hydrology Data Explorer and the National River Flow Archive.
How flow triggers help protect rivers and water supplies
Flow triggers are used to give us early warning when river levels begin to fall. They help us plan ahead and take the right action to protect both the environment and water supplies.
Rivers Test and Itchen
On the Rivers Test and Itchen, flow triggers are linked to the conditions in our abstraction licences. These include a hands‑off flow level, which is the point at which we must stop taking water from the river to protect it during low‑flow periods.
These flow triggers are also tied to the actions set out in our Drought Plan, helping us manage water supplies responsibly if river levels drop. At the moment, flows in both rivers are well above these trigger levels.
If river flows were to fall below the hands‑off flow level, we would need to apply for a drought permit. This would allow us to continue abstracting water in a controlled way, while still protecting the river and maintaining supplies for our customers.
How we manage river levels on the Isle of Wight
On the Isle of Wight, we take water from the River Yar under abstraction licences. When river levels are low, we can temporarily transfer water from the River Medina to the River Yar to help maintain healthy river levels. This is known as an augmentation scheme.
Currently, the scheme isn't in operation. When it is, we also support the River Medina using water from our groundwater sources, helping to protect the environment in both rivers. We keep the Environment Agency fully informed, as they oversee abstraction licences in the area.
Protecting Hampshire's rivers
During 2019, new rules were introduced to protect the Rivers Test and Itchen by controlling when we could take water for our customers. As a result, Hampshire faces an increased risk of drought during dry weather.
