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Upper River Colne and Radlett Brook

The Upper River Colne and Radlett Brook at Colney Heath, London Colney, Borehamwood and Radlett

Flood alert area River Colne Hertfordshire Herts and North London

Map

Nearby Monitoring Stations

London Colney in this area
River Colne • London Colney • 0.6 km (upstream)
Steady · normal
1.10 m
34min ago
Watford
River Colne • Watford • 8.3 km (upstream)
structure gauge
0.19 m
34min ago
Moor Lane
River Colne • Rickmansworth • 14.2 km (downstream)
Steady · normal
7.45 m
34min ago
Denham Colne
River Colne • Denham • 21.6 km (upstream)
Rising slightly · normal — Up 0.02 m since 10:00, rising slightly
0.13 m
34min ago
Willowbank
River Colne • Denham • 22.2 km (upstream)
structure gauge
0.84 m
34min ago
Iver, Clisbys Bridge
River Colne • Cowley • 25.1 km (downstream)
Easing · normal — Easing — down from 0.39 at 08:15, now 0.36
0.36 m
34min ago
Farlows Bridge
River Colne • Iver • 26.4 km (downstream)
Steady · normal
0.38 m
34min ago
West Drayton
River Colne • West Drayton • 27.5 km (downstream)
Steady · normal
0.43 m
34min ago
Thorney Mill Road, West Drayton (Temporary)
River Colne • West Drayton • 27.5 km (downstream)
Easing · normal — Easing — down from 0.12 at 09:15, now 0.08
0.08 m
34min ago
Colney Street
River Ver • Colney Street • 3.8 km
Steady · normal
0.16 m
34min ago

Flood Event History (50)

25 Oct 2026 at 8:53am Flood Alert
There is no longer a threat of flooding, though standing water and debris may still remain. Weather conditions are expected to improve. Further light rainfall is expected on Monday 26 October but no flooding is expected. We will continue to monitor the situation and will issue further alerts or warn...
24 Oct 2026 at 6:08pm Flood Alert
Rising river levels this evening may lead to flooding. Flooding is possible from the evening of Saturday 24 October due to heavy rainfall from Storm Austen and Boelo. Locations most affected will be low lying land and roads near rivers. Further heavy rain is forecast for this evening. We expect rive...
28 Aug 2026 at 9:08am Flood Alert
There is no longer a threat of flooding, though standing water and debris may still remain.  Weather conditions are expected to improve and no further flooding is expected.   We will continue to monitor the situation and will issue further alerts or warnings if necessary.   Continue to take care o...
27 Aug 2026 at 5:36pm Flood Alert
Rising river levels may lead to flooding this evening Thursday 27 August 2026 due to forecast heavy rain and storms. Locations most affected will be Waterside, Lowbell Lane, London Colney, Warrengate Road. Flooding from surface water, where water gathers and flows off road surfaces, could also occur...
27 Aug 2026 at 9:39am Flood Alert
Rising river levels may lead to flooding today Thursday 27 August 2026 due to forecast heavy rain and storms. Locations most affected will be Waterside, Lowbell Lane, London Colney, Warrengate Road. Flooding from surface water, where water gathers and flows off road surfaces, could also occur. We ex...
26 Aug 2026 at 9:38pm Flood Alert
High river levels overnight may lead to flooding.  Flooding is possible on 27 August 2026 Due to forecast heavy rain and storms overnight.  It is unclear where the heaviest rain will fall. Locations most affected will be low lying land, roads and riverside gardens. Flooding from surface water, where...
13 Mar 2026 at 9:47am Flood Alert
There is no longer a threat of flooding, though standing water and debris may still remain.  Weather conditions are expected to improve and no further flooding is expected.   We will continue to monitor the situation and will issue further alerts or warnings if necessary.   Continue to take care o...
12 Mar 2026 at 6:37pm Flood Alert
Rising river levels throughout the evening may lead to flooding.  Flooding is possible from overnight on 12 March 2026 to the following morning.  Locations most affected will be low lying land and roads near rivers.  We are closely monitoring the situation .  Take care and avoid walking, cycling or ...
18 Feb 2026 at 4:08pm Flood Alert
14 Feb 2026 at 5:04pm Flood Alert
5 Feb 2026 at 4:39pm Flood Alert
26 Jan 2026 at 5:05pm Flood Alert
20 Jan 2026 at 5:08pm Flood Alert
15 Jan 2026 at 4:28pm Flood Alert
8 Jan 2026 at 4:54pm Flood Alert
18 Dec 2025 at 4:57pm Flood Alert
5 Dec 2025 at 4:22pm Flood Alert
13 Nov 2025 at 4:09pm Flood Alert
19 Jul 2025 at 11:26am Flood Alert
6 Jul 2025 at 3:51pm Flood Alert
23 Feb 2025 at 7:09pm Flood Alert
5 Jan 2025 at 10:58am Flood Alert
6 Dec 2024 at 4:32pm Flood Alert
27 Nov 2024 at 11:00am Flood Alert
23 Nov 2024 at 6:32pm Flood Alert
1 Oct 2024 at 5:53pm Flood Alert
29 Sep 2024 at 6:06pm Flood Alert
26 Sep 2024 at 4:28pm Flood Alert
22 Sep 2024 at 8:29pm Flood Alert
15 Jul 2024 at 7:34pm Flood Alert
22 May 2024 at 7:22am Flood Alert
27 Apr 2024 at 6:29pm Flood Alert
26 Mar 2024 at 7:08pm Flood Alert
12 Mar 2024 at 10:28am Flood Alert
2 Mar 2024 at 8:14am Flood Alert
22 Feb 2024 at 1:36pm Flood Alert
21 Feb 2024 at 11:55am Flood Alert
17 Feb 2024 at 7:43pm Flood Alert
8 Feb 2024 at 2:21pm Flood Alert
4 Jan 2024 at 5:00pm Flood Alert
1 Jan 2024 at 5:34pm Flood Alert
19 Dec 2023 at 3:57pm Flood Alert
12 Dec 2023 at 3:44pm Flood Alert
9 Dec 2023 at 9:40am Flood Alert
13 Nov 2023 at 12:59pm Flood Alert
2 Nov 2023 at 5:57am Flood Alert
29 Oct 2023 at 2:12am Flood Alert
20 Sep 2023 at 4:52pm Flood Alert
30 Mar 2023 at 5:49pm Flood Alert
14 Jan 2023 at 1:45pm Flood Alert

Related Flood Areas

Ash Brook, Ippollitts Brook and River Purwell at Hitchin, Ashbrook, Little Wymondley and Graveley
River Ivel • Hertfordshire
Dane End tributary at Dane End
Beane • Hertfordshire
Groundwater flooding in Flamstead
Groundwater • Hertfordshire
Groundwater flooding in Kimpton and Lilley Bottom
Groundwater • Hertfordshire
Lower River Colne and Frays River
River Colne • Buckinghamshire, Greater London, Hertfordshire, Hillingdon, Slough, Surrey, Windsor and Maidenhead
Middle River Colne
River Colne • Greater London, Hertfordshire, Hillingdon
Mimmshall Brook at Warrengate Road
Mimmshall Brook • Hertfordshire
Radlett and Borehamwood Brooks at Borehamwood
Radlett Brook • Hertfordshire
Radlett Brook at Radlett
Radlett Brook • Hertfordshire
Rags Brook at Flamstead End
Rags Brook • Hertfordshire
River Ash at Furneux Pelham
Ash • Hertfordshire
River Ash at The Hadhams
Ash • Hertfordshire

Official sources for this area

This area on the Environment Agency’s flood service →
Floodline quick dial: 172728 — call 0345 988 1188 and give that code for a recorded update on this area.
Area code: 062WAF28UpColne

Live warnings and area boundaries are the Environment Agency’s and the EA is the authority on them. Contains public sector information licensed under the Open Government Licence v3.0. This area in the EA’s own data.