FloodRadar
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FloodRadar
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Get notified about Knowle Green — tick as many as you like, they all share the notify settings below.
Each one is saved as its own alert — pause or remove them individually any time.
Not an emergency service — if in danger call 999. Alerts rely on EA/SEPA/NRW data and are best-efforts. Terms
Geographic coordinates may reflect the access point for the gauge, and not the precise location in the watercourse that it is taking readings from.
Gauges connected to this river, and others nearby. A distance “by river” follows the river on the map; any other is in a straight line.
Distances by river: OS Open Rivers. Contains OS data © Crown copyright and database rights 2026.
None of the storm overflows FloodRadar holds is traced upstream of this gauge on the mapped river network. That is not the same as none: the map leaves out many small streams and culverts, so an overflow it cannot place may still drain here, and not every company publishes every overflow.
1 other overflow within 6 km is downstream of this gauge or on another branch of the river network, so it is not listed.
These are the water companies' monitor statuses; a spill does not by itself explain a change in the gauge level. River connections and distances are traced on OS Open Rivers (edition 2026-04), which leaves out many small channels. Explore the sewage map →
Contains OS data © Crown copyright and database rights 2026.
Loading rainfall and weather data...
This gauge rarely reaches its typical high of 0.81 m: 0 days since 2017. This year so far: 0 days.
Counted from each day's highest reading. Days with missing or implausible readings are left out.
Official Environment Agency warnings issued since 2014 for the 4 flood areas linked to this gauge (nearest 1.6 km away).
Most recent flood warning: 4 Jan 2024 — Chertsey Bourne at Chertsey
| Year | Warnings | Alerts |
|---|---|---|
| 2026 | 0 | 2 |
| 2024 | 1 | 0 |
| 2021 | 0 | 1 |
| 2014 | 2 | 2 |
Warnings apply to a whole flood area, not necessarily this exact spot. Years before 2006 aren't covered by the EA's historic record. See also the Staines flood history.
Flood warnings and alerts are issued for whole areas. These are the 4 areas linked to this gauge, nearest first.
The current level is 0.65m, which is within the typical range of 0.37 to 0.81m. Flooding is unlikely at this level.
Based on the most recent readings, the level is currently falling slightly. The chart above shows the last 12 hours of measurements by default (up to 7 days), updated roughly every 15 minutes.
When little or no rain has fallen for a while, a river level gradually drops as the water stored in the ground and soil drains away with nothing to replace it. This is called baseflow recession and is normal in dry spells. Only about 8.2mm of rain has fallen nearby in the last 7 days, so the flow is being sustained mainly by groundwater. A gentle decline like this is expected and is not a sign of a problem — downstream gauges often recede a little faster than headwaters further upstream, and levels recover once rain returns.
The typical range at this station is 0.37m to 0.81m, based on Environment Agency historical data. Levels above 0.81m are higher than usually seen and may indicate a flood risk.
Readings are supplied by the Environment Agency gauge. FloodRadar checks for updates roughly every 15 minutes; the timestamp above shows how recent the latest available reading is.
Free live river-level widget — ideal for parish councils, angling clubs and local sites. Updates automatically.
Postcodes within 5 km with properties in the Environment Agency’s rivers-and-sea flood-risk bands:
FloodRadar helper · beta