Ouse catchment
• Little Horsted • East Sussex • ID: E8293 • Level
(36m ago) • 4 readings/hr • 170 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.
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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Not an emergency service — if in danger call 999. Alerts rely on
EA/SEPA/NRW data and are best-efforts. Terms
Current Level
0.160 mASD
▬ Steady
24h Max
0.168 mASD
24h Min
0.149 mASD
Typical Range
0.05 - 1.50
mASD
Highest Recorded
2.90 mASD
EA official record
A 3.98 reading (4 Mar 2024) sits in our unverified raw history and is not treated as the record
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
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 2.2 km away along the river. 0 report discharging now, 7 report not discharging.
Southern Water · into Freshwater River · 4.7 km away in a straight line · its watercourse is not on the river map
14 spills · 44 hours in 2025
Not discharging now · last
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 →
In a typical year this gauge reaches its typical high of 1.50 m
on about 8 days.
This year so far: 10 days.
202610 days, 5 of them high · 5 highso far
20254 days, 1 of them high · 1 high
202416 days, 9 of them high · 9 high
202312 days, 7 of them high · 7 high
202214 days, 12 of them high · 12 high
20217 days, 1 of them high · 1 high
202010 days, 8 of them high · 8 high
201910 days, 6 of them high · 6 high
20181 day
20171 day
Counted from each day's highest reading. Days with missing or implausible readings are left out.
The darker part is days above 1.91 m, the level this gauge tops only a few days a year.
Flood history near this gauge
Official Environment Agency warnings issued since 2012 for the 6 flood
areas linked to this gauge (nearest 1.6 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 Little Horsted 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.
🌊 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
0.43
mixed response
Avg Annual Rainfall
882 mm/yr
1991–2020 · +5% since 1941–70
Urban Extent
3.0%
partly urbanised
Median Annual Flood
36.81 m³/s
QMED — typical yearly peak flow
Highest Daily Mean Flow
59.68 m³/s
12 Oct 2000 · 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.
Land Cover (2023)
Woodland 19%Grassland 66%Arable 8%Urban 7%
Grassland 70% → 66% since 1990
Flow affected by: effluent returns.
Photos
Gauging-station photographs from the National River Flow Archive (UKCEH).
Flat-V weir. Very responsive regime. Discharge from sewage treatment works affects low flows during summer. Automatic flood gates upstream at Uckfield Mill can produce abrupt flow changes.
More detail
The catchment
Catchment geology very mixed; Hastings Beds predominate. Above Isfield the catchment is rural with significant areas of woodland, but the Uckfield urban area is expanding. The River Uck is the principal tributary of the River Ouse.
The station
Flat-V weir (crest width 7.62m; 1:10 cross-slope) with cableway. Crest tapping (not currently instrumented) and some non-standard elements (e.g. experimental fish-ladder which has now been removed) between the abutments of a pre-existing Crump weir. Fish baffles installed in August 2019 on the downstream slope of the weir. Station is well sited downstream of railway embankment with large capacity bridge opening, 2km upstream of the Isfield Road Bridge. Superseded (in Sept 1999) a Crump profile weir (crest width 7.62m, crest level from bed 1.13m), with crest tapping. Flow capacity of earlier Crump was 51 cumecs but was subject to drowning in the mid flow range (10-30 cumecs), with a return to modular conditions at high flows due to overbank flow and the valley shape downstream. Prior to weir replacement (1999), retaining wall around old structure was in poor condition with the masonry on the right bank in danger of collapse.
How it measures flow
Flow gaugings using the crest tappings were made during about the first 10 years of operation. Weir was built with a 24 inch bypass pipe controlled by a penstock at its upstream end. Flow bypassing commenced at a gauged head of about 2.35m (51.61 cumecs) prior to April 2002. Following repair and rising of the eroded bank in April 2002, flow bypassing would occur at a gauged head of about 2.40m (55.85 cumecs). Present weir does not comply with British Standard 3680 requirements (upstream gauging location is closer to crest than recommended for gauged heads >1.4m approx). Experimental fish ladder installed on the downstream face, no effects noticed so far. Both original and existing weirs exhibit mid-range drowning (~10-30 cumecs). In 2002 a 6m section of the left hand bank immediately upstream of weir was rebuilt as was washed away, the bank around the weir was piled and work done on the upstream approach. Cableway installed in 1999 improved high flow capability; lots of check gaugings available. Ratings differ pre and post 1999 (when weir upgraded). Good confidence in mid-range flows although no account for remedial work in 2002 when bypassing reduced. All gaugings >2m are post remedial work and confirm that rating now overestimates flow. Two peak flow ratings applied across the period of record.
Flow regime
Very responsive regime. No substantial abstractions but discharge from sewage treatment works affects low flows during summer. Automatic flood gates upstream at Uckfield Mill can produce abrupt flow changes. Runoff increased by effluent returns. OUSENAT flow naturalisation scheme. Urban expansion around Uckfield.
The flow record
Data infilled with modelled data 30/07/2019-22/08/2019 due to fish baffle installation.
How this gauging station is built and how long it has measured (NRFA / UKCEH).
Gauge type
Flat-V weir
Operating since
1964
Station datum
11.3 mAOD
Flow record
1964–2024 · 60 yrs · 100% complete
Peak-flow record
since 1964
Hydrometric area
41
Measured by
Environment Agency
Nearby Groundwater
Soil Moisture
Frequently asked questions
Is the River Uck at Isfield weir flooding today?
The current level is 0.16m, which is within the typical range of 0.05 to 1.50m. Flooding is unlikely at this level.
Is the river level rising or falling at Isfield 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.
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 0.0mm 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 Uck at Isfield weir?
The typical range at this station is 0.05m to 1.50m, based on Environment Agency historical data. Levels above 1.50m 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.
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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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28 Sep 2000 Structure from downstream
28 Sep 2000 View from downstream with fish baffles
28 Sep 2000 View from downstream with fish baffles
28 Sep 2000 Cableway and hut
Upstream view of weir and gauging station hut
Downstream view of weir and gauging station hut