Bristol Avon Little Avon Axe and North Somerset St catchment
• Malmesbury • Wiltshire • ID: 531158 • Level
(23m ago) • 4 readings/hr • 122 views
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You'll be notified when this gauge is rising more than 0.10 m/hr — a sign of rapidly increasing water levels.
Beta. You'll be notified when a flood wave detected at an upstream gauge is forecast to reach this station, with an estimated arrival time. Accuracy improves as we verify more waves.
You'll be notified when a new storm-overflow (sewage) discharge starts within ~3 km of this gauge, based on the water companies' near-real-time feeds.
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Current Level
0.090 mASD
▬ Steady
24h Max
0.093 mASD
24h Min
0.088 mASD
Typical Range
0.09 - 0.54
mASD
Highest Recorded
1.48 mASD
EA official record
1.45 in our data (since May 2002)
Current level is 6% of this
🚽Sewage overflows nearby
Recent Water Levels
🌍 floodradar.co.uk
1 day
EA forecast (official)
Flood predictions aren't generated for
lock / structure gauges —
their levels are driven by gate operation,
not by catchment rainfall, so the forecast models would have no skill here.
River Flow
90 days
Daily mean discharge (m³/s) with the daily min–max band, from the EA Hydrology API. Flow is the volume of water passing the gauge — often a more direct flood signal than level.
Flow Data: Daily mean flow (m³/s) to 8 Oct (2 days behind — the EA publishes each day's mean a day or two after it ends; unchecked, provisional)via EA Hydrology
EA Cross-check: 0.09 mASD (EA at 10 Oct 02:45)
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.
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.
7 storm overflows are traced upstream of this gauge, the nearest 780 m away along the river. 0 report discharging now, 7 report not discharging.
Wessex Water · into Unnamed Ditch Trib Of Braydon · 5.3 km away in a straight line · its watercourse is not on the river map
34 spills · 549 hours in 2025
Not discharging now · last
11 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 →
In a typical year this gauge reaches its typical high of 0.54 m
on about 14 days.
This year so far: 19 days.
202619 days, 6 of them high · 6 highso far
202517 days, 7 of them high · 7 high
202430 days, 13 of them high · 13 high
202333 days, 9 of them high · 9 high
20222 days
20219 days, 2 of them high · 2 high
202019 days, 8 of them high · 8 high
201911 days, 1 of them high · 1 high
20185 days, 1 of them high · 1 high
20174 days, 1 of them high · 1 high
Counted from each day's highest reading. Days with missing or implausible readings are left out.
The darker part is days above 0.68 m, the level this gauge tops only a few days a year.
Flood history near this gauge
Official Environment Agency warnings issued since 2006 for the 6 flood
areas linked to this gauge (nearest 0.7 km away).
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 Malmesbury 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.
Is the Sherston Avon at St Johns Weir flooding today?
The current level is 0.09m, which is within the typical range of 0.09 to 0.54m. Flooding is unlikely at this level.
Is the river level rising or falling at St Johns Weir?
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.
What is a normal level for the Sherston Avon at St Johns Weir?
The typical range at this station is 0.09m to 0.54m, based on Environment Agency historical data. Levels above 0.54m 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:
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