Get notified about Ashton Weir — tick as many as you like, they all share the notify settings below.
Alert me when (tick one or more)
Height for "Above a height"
Drag the line on the chart, or type a value:m
Quick pick:
You'll be notified when this gauge is rising more than 0.10 m/hr — a sign of rapidly increasing water levels.
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.
Notify by (tick one or more)
Your browser will ask permission, then you'll get a notification even when FloodRadar isn't open.
On iPhone: tap Share → Add to Home Screen first, then open it from there and set the alert. Show me how
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
0.696 m
▼ Falling (-2cm/hr)
24h Max
1.068 m
24h Min
0.495 m
Typical Range
0.29 - 3.50
m
Highest Recorded
4.15 m
EA official record
A 12.77 reading (28 Feb 2025) sits in our unverified raw history and is not treated as the record
Current level is 17% of this
Current Flow
Loading...
🚽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
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.
176 storm overflows are traced upstream of this gauge, the nearest 750 m away along the river. 4 report discharging now, 162 report not discharging, and for 10 the monitor is offline or has not reported, so their status is not known.
United Utilities · into Bent Lanes Brook Via Sw Sewer · 2.2 km away in a straight line · its water cannot be followed on the map
54 spills · 176 hours in 2025
Not discharging now · last
42 more within 6 km whose connection is not known.
5 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 →
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 Urmston flood history.
Flood areas linked to this gauge
Flood warnings and alerts are issued for whole areas. These are the 23 areas linked to this gauge, nearest first.
🌊 Fairly flashyResponds fairly quickly to rain, with moderate baseflow between events.
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
0.41
mixed response
Avg Annual Rainfall
1,181 mm/yr
1991–2020 · +7% since 1941–70
Urban Extent
14%
partly urbanised
Median Annual Flood
167 m³/s
QMED — typical yearly peak flow
Highest Daily Mean Flow
222 m³/s
20 Jan 2021 · daily mean, not the instantaneous peak
Flow-Duration Curve
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.
Compound broad-crested weir with ultrasonics. Peak flows truncated by flood storage basins.
More detail
The catchment
A steep westward draining Pennine catchment with headwaters in the Peak District. Geology is a mixture of gritstones on high ground and Triassic marls and sandstones overlain with postglacial deposits in the west. Land use transition from open moorland to the heavily urbanised lower catchment (includes much of south Manchester).
The station
Station opened in 1958 as a replacement for Irlam Weir (69001) downstream. A compound broad-crested weir, 24m wide overall, with central lower section 12.2m wide and 0.49m lower than flanking crests (no divide piers). A 5-level cross-path Ultrasonic station was commissioned March 2009 just upstream of the weir, and upgraded in March 2024. A fish pass was added in March 2012 - ultrasonic flows are not affected. Two-stage channel profile, with a step at 4.5m and bankfull at 5.5m.
How it measures flow
The weir is insensitive at low flows and drowns at high flows. Flows contained - no bypassing. Low and medium flows generally reliable. Peak flows reliable since cross path ultrasonic gauge installed for high flow measurement in March 2009. Cableway demolished during construction of motorway in 1978, then re-instated for most recent high flow gaugings in late 1990's and removed late 2000's. Until March 2009 flows derived from rating, based on gaugings. High flow gaugings in 1998 from cableway revealed a complex stage-discharge pattern (hysteresis) above 100m3/s, which is thought to be due to variable backwater (differential drowning of the weir crest and seasonal variations in vegetation growth affecting the conveyance). Ultrasonic gauge confirms the hysteresis. A fish pass was added in March 2012 - ultrasonic flows are not affected. Flood Studies Report grade B.
Flow regime
Responsive regime despite substantial reservoir development in the headwaters (Longdendale reservoirs control 10% of the catchment). Several smaller reservoirs in the Tame and Goyt catchments control a further 13% of the catchment. Flood flows are truncated by operation of offline storage basins at Didsbury and Sale Ees upstream.
The flow record
Peak flows (over 100 m3s-1) before installation of the ultrasonic measurement in March 2009 are likely to be significantly overestimated. Full period of record peak flow data reviewed and released in October 2018 (WINFAP Files v7).
How this gauging station is built and how long it has measured (NRFA / UKCEH).
Gauge type
Gauging structure
Operating since
1958
Station datum
14.9 mAOD
Flow record
1976–2024 · 48 yrs · 99% complete
Peak-flow record
since 1958
Hydrometric area
69
Measured by
Environment Agency
Nearby Groundwater
Soil Moisture
Frequently asked questions
Is the River Mersey at Ashton Weir flooding today?
The current level is 0.70m, which is within the typical range of 0.29 to 3.50m. Flooding is unlikely at this level.
Is the river level rising or falling at Ashton Weir?
Based on the most recent readings, the level is currently falling. 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 River Mersey at Ashton Weir?
The typical range at this station is 0.29m to 3.50m, based on Environment Agency historical data. Levels above 3.50m 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: