← Back
Water Level Easing
Easing — down from 0.25 at 11:15, now 0.23
0.23

Swallowfield

Blackwater
Loddon catchment • Swallowfield • Wokingham • ID: 2469_w1TH • Level
(29m ago) • 4 readings/hr • 269 views

Set water level alerts

Get notified about Swallowfield — tick as many as you like, they all share the notify settings below.

⤴ Unusual rise — FloodRadar+Top 1% rise rate for this gauge.
Drag the line on the chart, or type a value: mASD
Quick pick:

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

Current Level
0.229 mASD
▼ Easing
24h Max
0.253 mASD
24h Min
0.229 mASD
Typical Range
0.19 - 0.95
mASD
Highest Recorded
1.48 mASD
EA official record
1.45 in our data (since Nov 2012)
Current level is 15% of this
🚽 Sewage overflows nearby

Recent Water Levels

🌍 floodradar.co.uk
1 day

Recent Readings

Falling · -1 cm over 5h
08 Oct 20:00 ▬ steady 0.229 mASD
08 Oct 19:45 ▬ steady 0.229 mASD
08 Oct 19:30 ▼ -0.1 cm 0.229 mASD
08 Oct 19:15 ▬ steady 0.230 mASD
08 Oct 19:00 ▬ steady 0.230 mASD
08 Oct 18:45 ▼ -0.1 cm 0.230 mASD
08 Oct 18:30 ▼ -0.1 cm 0.231 mASD
08 Oct 18:15 ▼ -0.1 cm 0.232 mASD
08 Oct 18:00 ▼ -0.1 cm 0.233 mASD
08 Oct 17:45 ▬ steady 0.234 mASD
08 Oct 17:30 ▬ steady 0.234 mASD
08 Oct 17:15 ▼ -0.1 cm 0.235 mASD
08 Oct 17:00 ▬ steady 0.236 mASD
08 Oct 16:45 ▼ -0.1 cm 0.236 mASD
08 Oct 16:30 ▼ -0.1 cm 0.237 mASD
08 Oct 16:15 ▬ steady 0.238 mASD
08 Oct 16:00 ▼ -0.1 cm 0.238 mASD
08 Oct 15:45 ▼ -0.1 cm 0.239 mASD
08 Oct 15:30 ▼ -0.1 cm 0.240 mASD
08 Oct 15:15 0.241 mASD

Station Details

  • Monitoring Station: Swallowfield
  • Watercourse: River Blackwater
  • Nearest Town: Swallowfield
  • County: Wokingham
  • Coordinates: 51°22'39"N 0°57'9"W (51.377564, -0.952526)
  • Open in: Google Maps · Apple Maps (opens your maps app)
  • Date Opened: 1 Jan 1986
  • Status: Active
  • Station Type: River level station
Technical details: references, datum, range, flow archive
  • Station Reference: 2469_w1TH
  • Also at this site: Swallowfield Side Channel (2469_w2TH, level, reporting)
  • RLOI id: 7149 (the EA's check-for-flooding station id)
  • EA Gauge ID: 2469_w1TH-level-stage-i-15_min-mASD
  • Parameter: Level
  • Unit: mASD
  • Typical rise rate: 1 cm/hr (p95 sustained over 90 days)
  • Typical data delay: ~22 min (measured reading→publication lag)
  • Tidal: No
  • Lock / structure: No
  • Catchment Area: Loddon
  • Typical Range: 0.189 – 0.950 mASD
  • EA Cross-check: 0.23 mASD (EA at 8 Oct 19:45)

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 upstream

Connected downstream

Same river system, separate branch

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

💧 Storm overflows upstream of this gauge

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.

12 storm overflows are traced upstream of this gauge, the nearest 4.4 km away along the river. 0 report discharging now, 11 report not discharging, and for 1 the monitor is offline or has not reported, so their status is not known.

💧
Thames Water · into Tributary Of River Blackwater · 4.4 km upstream along the river
27 spills · 325 hours in 2025
Not discharging now · last
💧
Thames Water · into Tributary Of The River Hart · 10.3 km upstream along the river
21 spills · 300 hours in 2025
Not discharging now · last
💧
Thames Water · into Rotherwick Brook · 11.3 km upstream along the river
8 spills · 74 hours in 2025
Not discharging now · last
Placed on the river by its position alone.
💧
Thames Water · into River Whitewater · 14.0 km upstream along the river
7 spills · 13 hours in 2025
Not discharging now · last
💧
Thames Water · into Blackwater · 14.2 km upstream along the river
10 spills · 115 hours in 2025
Not discharging now · last
💧
Thames Water · into Fleet Brook · 15.7 km upstream along the river
39 spills · 525 hours in 2025
Not discharging now · last
💧
Thames Water · into Blackwater · 17.7 km upstream along the river
7 spills · 69 hours in 2025
Not discharging now · last
💧
Thames Water · into Fleet Brook · 18.8 km upstream along the river
0 spills · 0 hours in 2025
Monitor offline: it cannot say whether it is discharging

4 more further upstream, up to 28.7 km away along the river.

2 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.

Rainfall & Weather

Loading rainfall and weather data...

How often this river runs high

In a typical year this gauge reaches its typical high of 0.95 m on about 15 days. This year so far: 17 days.

2026 17 days, 5 of them high · 5 high so far
2025 12 days, 7 of them high · 7 high
2024 36 days, 15 of them high · 15 high
2023 22 days, 7 of them high · 7 high
2022 11 days, 1 of them high · 1 high
2021 14 days, 4 of them high · 4 high
2020 26 days, 9 of them high · 9 high
2019 11 days, 4 of them high · 4 high
2018 4 days
2017 1 day

Counted from each day's highest reading. Days with missing or implausible readings are left out. The darker part is days above 1.12 m, the level this gauge tops only a few days a year.

Flood history near this gauge

Official Environment Agency warnings issued since 2011 for the 12 flood areas linked to this gauge (nearest 0.8 km away).

12flood warnings 202flood alerts

Most recent flood warning: 27 Jan 2025 — River Loddon and River Blackwater at Swallowfield

Year by year
YearWarningsAlerts
2026 0 8
2025 1 11
2024 1 21
2023 2 15
2022 0 6
2021 1 12
2020 1 14
2019 2 10
2018 0 12
2017 0 10
2016 0 19
2015 0 10
2014 3 22
2013 1 10
2012 0 19
2011 0 3

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 Swallowfield flood history.

Flood areas linked to this gauge

Flood warnings and alerts are issued for whole areas. These are the 12 areas linked to this gauge, nearest first.

Show 4 more

Frequently asked questions

Is the River Blackwater at Swallowfield flooding today?

The current level is 0.23m, which is within the typical range of 0.19 to 0.95m. Flooding is unlikely at this level.

Is the river level rising or falling at Swallowfield?

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.

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 9.6mm 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 River Blackwater at Swallowfield?

The typical range at this station is 0.19m to 0.95m, based on Environment Agency historical data. Levels above 0.95m 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.

Embed this gauge on your website

Free live river-level widget — ideal for parish councils, angling clubs and local sites. Updates automatically.

Preview

📮 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 →