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0.89

Borehamwood

Borehamwood Brook
Colne (Upper) catchment • Green Street • Hertfordshire • ID: 2821TH • Level
(21m ago) • 4 readings/hr • 187 views

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Current Level
0.888 mASD
▬ Steady
24h Max
0.895 mASD
24h Min
0.887 mASD
Typical Range
0.83 - 1.80
mASD
Highest Recorded
2.22 mASD
EA official record
2.22 in our data (since Nov 2009)
Current level is 40% of this
🚽 Sewage overflows nearby

Recent Water Levels

🌍 floodradar.co.uk
1 day

Recent Readings

Steady over 5h
10 Oct 13:15 ▲ +0.1 cm 0.888 mASD
10 Oct 13:00 ▼ -0.1 cm 0.887 mASD
10 Oct 12:45 ▬ steady 0.888 mASD
10 Oct 12:30 ▬ steady 0.888 mASD
10 Oct 12:15 ▬ steady 0.888 mASD
10 Oct 12:00 ▼ -0.1 cm 0.888 mASD
10 Oct 11:45 ▲ +0.2 cm 0.889 mASD
10 Oct 11:30 ▬ steady 0.887 mASD
10 Oct 11:15 ▬ steady 0.887 mASD
10 Oct 11:00 ▼ -0.1 cm 0.887 mASD
10 Oct 10:45 ▬ steady 0.888 mASD
10 Oct 10:30 ▬ steady 0.888 mASD
10 Oct 10:15 ▬ steady 0.888 mASD
10 Oct 10:00 ▬ steady 0.888 mASD
10 Oct 09:45 ▬ steady 0.888 mASD
10 Oct 09:30 ▬ steady 0.888 mASD
10 Oct 09:15 ▬ steady 0.888 mASD
10 Oct 09:00 ▬ steady 0.888 mASD
10 Oct 08:45 ▬ steady 0.888 mASD
10 Oct 08:30 0.888 mASD

Station Details

Technical details: references, datum, range, flow archive
  • Station Reference: 2821TH
  • RLOI id: 7006 (the EA's check-for-flooding station id)
  • EA Gauge ID: 2821TH-level-stage-i-15_min-mASD
  • Parameter: Level
  • Unit: mASD
  • Typical rise rate: 5 cm/hr (p95 sustained over 90 days)
  • Typical data delay: ~22 min (measured reading→publication lag)
  • Tidal: No
  • Lock / structure: No
  • Catchment Area: Colne (Upper)
  • Typical Range: 0.827 – 1.800 mASD
  • EA Cross-check: 0.89 mASD (EA at 10 Oct 12:45)

Geographic coordinates may reflect the access point for the gauge, and not the precise location in the watercourse that it is taking readings from.

Nearby Stations

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.

Connected downstream

Same river system, separate branch

Nearby

Distances by river: OS Open Rivers. Contains OS data © Crown copyright and database rights 2026.

💧 Storm overflows upstream of this gauge

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. Those nearby are listed below.

Nearby, connection not known

Within 6 km in a straight line, but the river map cannot say whether their water passes this gauge.

💧
Thames Water · into Colne Brook · 5.3 km away in a straight line · its watercourse is not on the river map
0 spills · 0 hours in 2025
Not discharging now
💧
Thames Water · into Kitts End Stream · 5.5 km away in a straight line · its watercourse is not on the river map
0 spills · 0 hours in 2025
Status unknown — the live feed has not updated for 129 d 22 h

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.

Rainfall & Weather

Loading rainfall and weather data...

How often this river runs high

In a typical year this gauge reaches its typical high of 1.80 m on about 1 day. This year so far: 0 days.

2026 0 days so far
2025 2 days
2024 1 day
2023 1 day
2022 1 day
2021 1 day
2020 2 days
2019 0 days
2018 0 days
2017 0 days

Counted from each day's highest reading. Days with missing or implausible readings are left out.

Flood history near this gauge

Official Environment Agency warnings issued since 2009 for the 6 flood areas linked to this gauge (nearest 0.6 km away).

2flood warnings 10flood alerts

Most recent flood warning: 19 Jul 2025 — Radlett and Borehamwood Brooks at Borehamwood

Year by year
YearWarningsAlerts
2025 1 0
2024 0 2
2021 1 1
2014 0 3
2012 0 2
2010 0 1
2009 0 1

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 Green Street flood history.

Flood areas linked to this gauge

Flood warnings and alerts are issued for whole areas. These are the 6 areas linked to this gauge, nearest first.

Frequently asked questions

Is the Borehamwood Brook at Borehamwood flooding today?

The current level is 0.89m, which is within the typical range of 0.83 to 1.80m. Flooding is unlikely at this level.

Is the river level rising or falling at Borehamwood?

Based on the most recent readings, the level is currently steady. The chart above shows the last 12 hours of measurements by default (up to 7 days), updated roughly every 15 minutes.

Why is the level slowly falling?

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 5.8mm 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.

What is a normal level for the Borehamwood Brook at Borehamwood?

The typical range at this station is 0.83m to 1.80m, based on Environment Agency historical data. Levels above 1.80m are higher than usually seen and may indicate a flood risk.

How often is this river level data updated?

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.

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📮 Flood risk by postcode near this gauge

Postcodes within 5 km with properties in the Environment Agency’s rivers-and-sea flood-risk bands:

Check any UK postcode’s flood risk →

🏠 Buying or renting around here? Get the Property Flood-Risk Report for any English postcode — official risk band, recorded floods, warning history, river behaviour and nearby storm overflows. £19 one-off. Learn more →