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Ewell GS

Unknown
• Surrey • ID: 3350THF • Flow
(32m ago) • 4 readings/hr • 156 views
Current Flow
0.014 m3/s
▬ Steady
24h Max
0.016 m3/s
24h Min
0.014 m3/s
Typical Range
-
Highest Recorded
0.22 m3/s
23 Jun 2026
Since Feb 2025
🚽 Sewage overflows nearby

Recent Flow Readings

🌍 floodradar.co.uk
1 day

Recent Readings

Steady over 6h
09 Oct 19:15 ▬ steady 0.014 m3/s
09 Oct 19:00 ▬ steady 0.014 m3/s
09 Oct 18:45 ▬ steady 0.014 m3/s
09 Oct 18:30 ▬ steady 0.014 m3/s
09 Oct 18:15 ▬ steady 0.014 m3/s
09 Oct 18:00 ▬ steady 0.015 m3/s
09 Oct 17:45 ▼ -0.1 cm 0.015 m3/s
09 Oct 17:30 ▬ steady 0.016 m3/s
09 Oct 17:15 ▲ +0.1 cm 0.016 m3/s
09 Oct 17:00 ▬ steady 0.015 m3/s
09 Oct 16:45 ▬ steady 0.014 m3/s
09 Oct 16:30 ▬ steady 0.014 m3/s
09 Oct 16:00 ▬ steady 0.014 m3/s
09 Oct 15:30 ▬ steady 0.014 m3/s
09 Oct 15:00 ▬ steady 0.014 m3/s
09 Oct 14:45 ▬ steady 0.014 m3/s
09 Oct 14:30 ▬ steady 0.014 m3/s
09 Oct 14:15 ▬ steady 0.014 m3/s
09 Oct 14:00 ▬ steady 0.014 m3/s
09 Oct 13:45 0.014 m3/s

Station Details

  • Monitoring Station: Ewell GS
  • Watercourse: —
  • County: Surrey
  • Coordinates: 51°21'21"N 0°15'18"W (51.355811, -0.255109)
  • Open in: Google Maps · Apple Maps (opens your maps app)
  • Status: Active
  • Station Type: Flow gauging station (inferred)
Technical details: references, datum, range, flow archive
  • Station Reference: 3350THF
  • Also at this site: Ewell (3350TH, level, reporting)
  • EA Gauge ID: 3350THF-flow--i-15_min-m3_s
  • Parameter: Flow
  • Unit: m3/s
  • Typical data delay: ~22 min (measured reading→publication lag)
  • Tidal: No
  • Lock / structure: No
  • Drainage Area: 34 km² upstream of this gauge
  • Flow Archive: National River Flow Archive ↗

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

At this site

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 Green Lanes Stream · 1.3 km away in a straight line · its recorded watercourse is not the one mapped beside it
2 spills · 2 hours in 2025
Not discharging now · last
💧
Thames Water · into Old Pyl Ditch · 5.5 km away in a straight line · no mapped watercourse close enough to be sure
1 spill · 1 hours in 2025
Not discharging now · last

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...

Flood history near this gauge

Official Environment Agency warnings issued since 2012 for the 5 flood areas linked to this gauge (nearest 1.3 km away).

1flood warning 56flood alerts

Most recent flood warning: 29 Oct 2023 — Pyl Brook at North Cheam

Year by year
YearWarningsAlerts
2025 0 2
2024 0 3
2023 1 1
2022 0 5
2021 0 10
2020 0 3
2019 0 6
2018 0 6
2017 0 7
2016 0 4
2014 0 2
2013 0 3
2012 0 4

Warnings apply to a whole flood area, not necessarily this exact spot. Years before 2006 aren't covered by the EA's historic record.

Flood areas linked to this gauge

Flood warnings and alerts are issued for whole areas. These are the 5 areas linked to this gauge, nearest first.

Catchment Character

🌊 Urban & flashy Heavily built-up — rain runs off hard surfaces fast, so levels can spike within hours of heavy rain.

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).

Baseflow Index
0.88
groundwater-fed — slow & steady
Avg Annual Rainfall
700 mm/yr
1991–2020 · -1% since 1941–70
Urban Extent
37%
heavily urbanised
Highest Daily Mean Flow
0.247 m³/s
17 May 2001 · daily mean, not the instantaneous peak
Flow-Duration Curve
mean 0.0480.1310.0350.0025% (high)% of days exceeded95% (low)
Daily flow (m³/s) exceeded each % of the time — a steep curve is flashy, a flat one is steady. Q5 high · Q50 median · Q95 low.
Land Cover (2023)
Woodland 3%Grassland 30%Urban 66%

About this gauge

Rectangular flume; stage-discharge relation confirmed by c/m gaugings.

More detail

The catchment

A largely suburban catchment developed mostly on Chalk (dip-slope of North Downs). Mean runoff suggests that topographical catchment greatly exceeds the contributing area.

The station

Rectangular flume; Modular. Overfall u/s. Frequently vandalised. Station downgraded in 2010 to level only.

How it measures flow

Grounding of float (stilling well floor corresponds to throat level of flume) can affect low flow accuracy. Debris on u/s grill can influence levels.

The flow record

Patchy flow record.

Descriptions from the National River Flow Archive (UKCEH). NRFA station record ↗

Gauge Details

How this gauging station is built and how long it has measured (NRFA / UKCEH).

Gauge type
Gauging structure
Operating since
1988–2010
Station datum
28.6 mAOD
Flow record
1988–2010 · 22 yrs · 84% complete
Hydrometric area
39
Measured by
Environment Agency

Frequently asked questions

Is Ewell GS flooding today?

The latest recorded level is 0.01m. Compare it with the recent history on the chart above to judge whether levels are unusually high.

Is the river level rising or falling at Ewell GS?

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.

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 →