Natural Resources Wales does not publish a typical range for this gauge, so FloodRadar
works one out from its own history (its usual daily lows and highs). It is not an official flood threshold.
(34m ago) • 4 readings/hr • 8 views
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Get notified about Ynysddu River Station — tick as many as you like, they all share the notify settings below.
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⤴Unusual rise — FloodRadar+Top 1% rise rate for this gauge.
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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 storm overflow starts discharging, from the water companies' near-real-time feeds. Which overflows:
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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
Experimental model fusing soil moisture, river flow, groundwater and catchment
character. The shaded band is its 10–90% range, widened so that about 80% of recent outcomes fall inside it.
Under evaluation — not yet promoted, so treat as a second opinion.
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.
32 storm overflows are traced upstream of this gauge, the nearest 1.7 km away along the river. 0 report discharging now, 29 report not discharging, and for 3 the monitor is offline or has not reported, so their status is not known.
Dwr Cymru Welsh Water · into River Rhymney · 3.7 km away in a straight line · not connected to this gauge on the river map
Not discharging now · last
24 more within 6 km whose connection is not known.
12 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. Sewage & storm overflows →
In a typical year this gauge reaches its typical high of 0.96 m
on about 22 days.
This year so far: 7 days.
20267 days, 1 of them high · 1 highso far
202524 days, 7 of them high · 7 high
202419 days, 3 of them high · 3 high
Counted from each day's highest reading. Days with missing or implausible readings are left out.
The darker part is days above 1.26 m, the level this gauge tops only a few days a year.
Nearby Groundwater
Soil Moisture
Possible storm-overflow correlation
Related gauges
Measured from a year of how these gauges actually moved.
Timing, not cause. Gauges can move together simply because the same rain fell on both.
Frequently asked questions
Is the Sirhowy at Ynysddu River Station flooding today?
The current level is 0.58m, which is within the typical range of 0.21 to 0.96m. Flooding is unlikely at this level.
Is the river level rising or falling at Ynysddu River Station?
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 Sirhowy at Ynysddu River Station?
The typical range at this station is 0.21m to 0.96m, based on Natural Resources Wales historical data. Levels above 0.96m are higher than usually seen and may indicate a flood risk.
How often is this river level data updated?
Readings are supplied by the Natural Resources Wales 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.
River readings supplied by Natural Resources Wales. FloodRadar checks for updates every 15 minutes; the reading timestamp shows the latest available observation.
The Environment Agency’s flood-zone map covers England. In Wales the Area map’s Flood Zones layer is Natural Resources Wales’s Flood Map for Planning, drawn by FloodRadar from its copy of NRW’s shapes where it holds them: an empty patch is not an absence of flood risk. Check NRW for official Welsh flood warnings and information.