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Get notified about Horley — 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.
Storm overflows whose water reaches this gauge on the mapped river network, nearest first by distance along the river. The status is each water company's monitor: it says whether an overflow is discharging, not how much or what it contains.
1 storm overflow is traced upstream of this gauge, the nearest 4.8 km away along the river. 0 report discharging now, 1 reports not discharging.
Within 6 km in a straight line, but the river map cannot say whether their water passes this gauge.
6 other overflows within 6 km are downstream of this gauge or on another branch of the river network, so they are 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...
In a typical year this gauge reaches its typical high of 2.42 m on about 6 days. This year so far: 4 days.
Counted from each day's highest reading. Days with missing or implausible readings are left out.
Official Environment Agency warnings issued since 2012 for the 13 flood areas linked to this gauge (nearest 0.9 km away).
Most recent flood warning: 24 Dec 2022 — Weatherhill Stream at Smallfield
| Year | Warnings | Alerts |
|---|---|---|
| 2026 | 0 | 7 |
| 2025 | 0 | 11 |
| 2024 | 0 | 22 |
| 2023 | 0 | 14 |
| 2022 | 4 | 8 |
| 2021 | 0 | 6 |
| 2020 | 3 | 8 |
| 2019 | 5 | 14 |
| 2018 | 0 | 2 |
| 2017 | 0 | 3 |
| 2016 | 0 | 13 |
| 2015 | 0 | 4 |
| 2014 | 18 | 9 |
| 2013 | 6 | 8 |
| 2012 | 6 | 11 |
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 Horley flood history.
Flood warnings and alerts are issued for whole areas. These are the 13 areas linked to this gauge, nearest first.
Your catchment is all the land that drains rainfall into the river above this gauge. Its character — how steep, wet, wooded, urban or chalky that land is — decides how fast rain here turns into a rising river. A steep, bare or clay catchment is “flashy” (rises and falls quickly, floods easily); a flat, chalk or well-wooded one is slow and steady. The tiles below put numbers to that; the flow-duration curve reads left-to-right from the river’s typical high flows (Q5) down to its low flows (Q95) — a steep curve means a flashy river.
The physical character of the land that drains to this gauge, and how it shapes its flood response — from the National River Flow Archive (UKCEH).
Flow affected by: public water supply, effluent returns.
Gauging-station photographs from the National River Flow Archive (UKCEH).
May 1985 Upstream view to gauging station
May 1985 Approach channel
May 1985 Downstream of weir
May 1985 Channel downstream
May 1985 Weir
View of weir profile from right bank
View of weir looking upstream from right bank
View of downstream road Bridge looking downstream from left bank (during flood conditions)
Downstream view
Photos © NRFA / UKCEH & the measuring authority — shown at web resolution. Full gallery on the NRFA ↗
Compound broad-crested weir. Runoff reduced by public water supply abstraction and increased by increasing sewage effluent contribution.
Descriptions from the National River Flow Archive (UKCEH). NRFA station record ↗
How this gauging station is built and how long it has measured (NRFA / UKCEH).
The current level is 0.46m, which is within the typical range of 0.19 to 2.42m. Flooding is unlikely at this level.
Based on the most recent readings, the level is currently falling. 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. 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 0.19m to 2.42m, based on Environment Agency historical data. Levels above 2.42m 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:
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