Data sources
•
OPW waterlevel.ie
— ~380 river gauge stations, updated every 15 min
•
Open-Meteo
— precipitation forecast & soil moisture (no key, CC-BY)
•
Met Éireann
— active weather warnings & NWP forecast
•
OPW Flooding.ie
— statutory flood risk zones (APSFR)
•
OpenStreetMap
— road & bridge proximity analysis
How the score works
Each station is scored 0–100 from up to 8 independent signals.
Signals are additive; reaching 70+ triggers a WARNING, 85+ an ALERT.
The score is recalculated every 3 hours using live gauge and weather data.
Where a trained ML model exists for a station, its flood probability prediction is blended
with the rule score (40–60% ML weight depending on model accuracy). The ML adjustment is
shown in the score breakdown as a separate line. Stations show a
Station ML or
Global ML badge depending on whether a per-station or fallback model is used.
Validated case study
Retrospective simulation of the River Slaney flood (Enniscorthy, Jan 27 2026)
shows FloodGauge would have issued an ALERT
24+ hours in advance,
driven by 513mm of 90-day rainfall (88th percentile) + 47mm forecast rain.
FAQ
Why is my station not shown? — Some OPW gauges report infrequently or are temporarily
offline. Only stations with a recent reading are displayed.
Why did the score jump suddenly? — A rapid rise in river level or a new
rainfall forecast can add 20–30 pts in one cycle. The ML model may also adjust
the score based on the station’s flood history.
What does MONITOR mean? — Multiple signals are active (score 40–69) but
conditions are not yet at WARNING level. Worth watching if you’re near the river.
How accurate is this? — When it warns, it is rarely a false alarm:
replayed across a full year of gauge records (~129,000 checks) it raised
effectively no false warnings. How many floods it catches is still being proven
on the small live record since March 2026 — the accuracy dashboard shows
precision and recall with 95% confidence intervals, and they will firm up as
the 2026 flood season adds real events. Built by someone who works in IT with an
enthusiast's interest in weather — not a meteorologist or flood
professional, and not reviewed by any. Some stations have limited history and
carry a ⚠ caution badge.
How often is it updated? — Every 3 hours during flood season (Oct–Apr),
and twice daily (morning and evening) over the summer (May–Sep). The
"Updated" time shown with each map is the most recent run.
What about the flood-zone & pluvial layers? — All reference
layers (CFRAM flood zones, the Ireland-wide pluvial susceptibility heatmap) are
available on every device. The map loads fast with just the gauges, then pulls
the heavier layers in the background so they’re ready the moment you toggle
them on in the layer control (top-right).
Limitations
Stations with fewer than 1,000 historical readings carry a ⚠ caution
badge — their flood thresholds may be less accurate.
This is an independent research tool, not an official service.