FloodWatch Ireland: a free watch on the State's flood data, built in public
Superseded, 26 September 2026. The current version is Flood warnings Ireland: what 461 State gauges say, checked, which carries the full record behind this piece.
We built a small free service. It watches the State's flood data and emails you when water is heading for your town.
It is called FloodWatch Ireland. It runs on a server we pay for, and using it costs nothing.
What it watches
- 159 flood-zone datasets: Office of Public Works and local authority maps, 17 layers, 26 counties.
- 461 river gauges, polled on a timer. The latest reading is kept for each one.
- Live warnings, matched against the area you asked about as they are issued.
You name a town, or an eircode with a radius. It watches that patch and nothing else.
What an alert looks like
An email lands when a gauge near you crosses its threshold, or when a flood zone covering your address goes active. One email per event. No daily digest. Nothing else in your inbox.
Why we built it
Two reasons. The State's flood data is genuinely good. It sits in county-by-county map services that nobody opens on a wet Tuesday. And it is the same job we do for clients: take a public dataset, watch it, tell someone when the answer changes.
Where it stands
Plainly, the watching is finished and running. Completed so far: 1,221 checks, 50 warnings logged. Delivery is not finished. While we test the mail rail on a small list, alerts queue instead of sending. Anyone signing up today joins the test list, not a live alerting list. We will say so here when the rail is switched on.
A town and an email address is all the form asks for, plus a confirmation link and a one-click unsubscribe. No phone number. No card. Nothing sold on.
Browse FloodWatch Ireland, or tell us about a dataset you would like watched. Same pattern. Another subject.