Flood risk on your Irish farm: read the OPW maps against your own parcels

You can check flood risk on your Irish farm for free, from the kitchen table. The OPW flood maps on floodinfo.ie show the river and coastal bands, from a 1 in 10 chance a year down to 1 in 1,000. Your parcels are on agfood.ie. Lay one over the other, parcel by parcel. Then you know which fields to keep stock off, where not to spread, and where not to build.

Checked 26 October 2026. Storm Boelo brought very heavy rain to the west overnight into Saturday, says the National Severe Weather and Flood Coordination Group. Donegal, Galway, Leitrim, Mayo and Sligo were under an Orange wind warning. By Sunday the group reported spot flooding, saturated soils, and river levels staying high in the west and southwest into Tuesday. The Government's Severe Weather Advice page was updated on 26 October with a flooding section that points to the OPW's flood pages. Met Éireann issued a Status Yellow wind warning for eleven counties for the evening of Monday 26 October.

Where do the OPW flood maps live?

Everything is on floodinfo.ie, the OPW's flood portal. Three parts matter to a farmer.

The Flood Maps Viewer holds the predictive maps from the CFRAM programme. You search an address or zoom to the land, then switch layers on and off. The maps were built for 300 communities judged to be at significant risk, plus the river reaches between them and the sea. The OPW calls them community-based maps and says plainly that they are not there to designate individual properties.

The Past Flood Events layer is different. It records floods that actually happened, with reports, photographs and press cuttings behind each point. Points are approximate. A quality code of 1 means a detailed engineer's record; lower codes mean an estimated date or location. No point does not mean no flood. It means nobody filed one.

waterlevel.ie gives live readings from OPW gauges. The data is provisional and unchecked, but it tells you whether the river beside your land is still rising. That is the question that matters on a Monday after a storm.

What do the layers and probability bands mean?

The maps use Annual Exceedance Probability, or AEP. It is the chance of a flood that size, or bigger, in any one year. The OPW's map guidance notes set out the bands:

Three things trip people up.

"1 in 100" is not once a century. It is a 1% chance every year, and two bad floods can land a winter apart. The OPW says this itself in the notes.

Fluvial and coastal are separate layers. Fluvial is the river overtopping its banks. Coastal is tide plus surge plus waves. If your land sits on an estuary, turn on both.

Pluvial is mostly missing. Pluvial flooding is heavy rain ponding in hollows before it ever reaches a river. The OPW has mapped it for Raphoe in Donegal and Dublin City only. For most farms, a field that fills from the sky is not on any map.

The notes also carry the limits. River models assume every culvert and bridge runs clear; a blocked pipe is not modelled. Water levels are calibrated to roughly plus or minus 0.2 metres inside the 300 communities and 0.4 metres on the rivers between them. Outside the communities, channel cross-sections were surveyed about every 500 metres. Hatched areas show land behind an existing defence, which the OPW says lowers the chance of flooding but does not remove it.

The viewer also offers two climate scenarios. The mid-range future adds 20% to extreme rainfall and 500 mm to sea level; the high-end adds 30% and 1,000 mm. If you are siting a shed for 40 years, look at those layers too.

How do you find your own parcels and lay them on the map?

There is no button that does this for you. The parcel maps and the flood maps live in two systems, and neither talks to the other. The job is two screens and a notebook.

1. Open your parcels. Log in to agfood.ie. The BISS land details screen lists every parcel by its LPIS number. The map viewer shows each one, with a Layers menu for reference layers. Screenshot each parcel at a zoom where you can see the field boundary and the nearest river, drain or road.
2. Open the flood map at the same place. In the floodinfo.ie viewer, search the townland. Turn on the fluvial medium and low layers, the coastal layers if you are near the sea, and Past Flood Events. Screenshot the same view.
3. Match the landmarks. The river, the road and the yard are on both pictures. Mark each parcel one of four ways. Inside the medium band; inside the low band only; outside every mapped extent; or close to a past flood point.
4. Check the gauge. Find the nearest station on waterlevel.ie and note its level today against the past weeks.

If your land is outside the 300 communities and off the modelled reaches, there may be no coloured band at all. That is a gap in the mapping, not a clean bill of health. The OPW's own Before a Flood page says to use local history, neighbours and the Past Flood Events layer. It also points to the words "liable to floods" on the older Ordnance Survey sheets.

What does the result change on the farm this winter?

Stock on the land. Teagasc's standing severe weather advice is to move outwintered animals to higher ground with access for feed, and to talk to neighbours about shed space. Any parcel in the medium band, or beside a past flood point, is the one to clear first. Contact the local DVO if animals are at risk.

Slurry and fertiliser. The closed period is already in force; our slurry and fertiliser deadlines page has the dates. When spreading reopens, the regulations bar slurry, fertiliser or soiled water on land that is waterlogged, flooded or likely to flood. The same bar applies when heavy rain is forecast within 48 hours. Heavy rain means a Met Éireann yellow, orange or red rainfall warning. Teagasc's buffer table gives the distances. Keep 5 m from surface waters, and 10 m where the slope towards the water is over 10%. The 10 m also applies for two weeks either side of the closed period. Keep 20 m from a lake shore or a turlough likely to flood, and 15 m from karst features. A parcel in the medium band is the obvious candidate for "likely to flood". The regulations do not define that phrase by map band, so settle it with your advisor. Plan your spring spreading around it, and keep the LPIS number in your records.

Slurry storage. If floodwater reaches the yard, Teagasc's advice is to pump out only what is needed to protect animals, onto the driest ground away from watercourses. Once water is above the passageway there is no point pumping; the tank refills. Longer term, Teagasc's 25 October note says to keep clean rainwater out of tanks now. Plan for 0.40 cubic metres per dairy cow per week from 1 October 2028.

A new shed. The planning guidelines on gov.ie define three zones. Flood Zone A is more than a 1 in 100 river chance, or 1 in 200 coastal. Zone B is between 1 in 1,000 and 1 in 100. Zone C is the rest. Farm buildings count as less vulnerable development. In Zone A they face the Justification Test. In Zone B they should only be considered if no Zone C site is available, and with a flood risk assessment. Teagasc's TAMS 3 note is that planning permission, or a declaration of exemption with stamped drawings, must be in place before you apply. Exemptions were widened at the end of 2025; qualifying animal housing can now reach 300 square metres per structure. An exempt shed is still a shed in a flood zone if you put it there. The map is the cheapest site visit you will ever get.

Evidence. Photograph any flooding on your parcels with the date, and mark the water line. The OPW asks for reports at reportfloodevent@opw.ie, and the Past Flood Events layer is built from exactly that. Your own catchment matters too; our guide to finding your catchment report shows where the EPA water-quality evidence sits beside the flood evidence.

What supports exist after a flood?

As of 26 October 2026, there is no DAFM flood scheme open. We searched gov.ie today and found none.

The precedent is the Shannon Callows Flood Scheme 2023. It paid up to €325 a hectare for fodder lost to summer flooding, with a 1 ha minimum and a 15 ha cap. DAFM identified eligible parcels through its Area Monitoring System on land claimed in that year's BISS. If a scheme follows this winter, that is how it will likely find you: through the parcels you declared, not through a phone call. Keep your declarations and your photographs straight.

The Office of Emergency Planning's flooding guide lists two schemes. The Emergency Humanitarian Flooding Scheme covers small businesses, run through the Irish Red Cross. The Emergency Response Payment covers damaged homes. Whether a farm business qualifies under the first is a question for the scheme, not for us.

For feed, Teagasc's local office helps with fodder budgets, and with checking silage pH where water got into a pit. For animal welfare or movement queries, the DVO. For your own safety, Teagasc's list is short. Do not enter floodwater unless you must. Tell someone where you are going, and keep a charged phone in a zipped pocket.

What can an AI assistant honestly do here?

Less than the adverts suggest, and still something useful.

It can read a screenshot of the floodinfo.ie legend and explain it in plain words. It can take the table above and turn it into a checklist for your parcels, in whatever order you want. It can draft the note to your advisor or your planner, with the AEP figures and the Teagasc distances in it. It can take a Met Éireann warning you paste in and tell you whether it meets the heavy-rain definition in the regulations.

It cannot see your parcels. Agfood is behind your login, and no assistant has it. It cannot lay two screenshots over each other to the metre; it will guess, and a guess about a field boundary is worth nothing. It cannot predict whether your field floods this week. The OPW's own models carry a 0.2 metre margin and assume clear culverts; a chatbot has neither the survey nor the gauge. And it cannot tell you the closed period for your county without being handed the source.

A prompt that stays inside those limits:

Using only the OPW map guidance text and the Teagasc buffer table I paste below, make a checklist for one farm parcel. The parcel sits inside the 1% AEP fluvial band and borders a drain. Cover stock, slurry spreading distances, storage, and whether a new shed would face the planning Justification Test. Give the source line for every item. Do not guess my location or my parcel numbers.

Check its answer against the pasted text. Delete anything it added. Keep your herd number, your PAC and your login out of it. Our test of free weather data for your own farm found the same rule for rainfall. The free source is good; the shortcut is where it goes wrong.

Frequently asked questions

My townland is not one of the 300 communities. Is there a flood map for me?

Probably not a predictive one. The CFRAM maps cover the 300 areas and the main rivers between them. Use the Past Flood Events layer, the Ordnance Survey "liable to floods" marking, waterlevel.ie and your neighbours. A blank map is a gap, not a verdict.

Does the 1 in 100 band mean one flood a century?

No. It means a 1% chance in every year, and the OPW notes say two severe floods can come close together. Storm Boelo's rain fell on ground the coordination group already called saturated, days after Storm Austen.

Can I spread slurry on a parcel the map shows in the low band?

The map is not the test; the ground is. The regulations prohibit spreading on land that is waterlogged, flooded or likely to flood, or when heavy rain is forecast within 48 hours. The buffer distances from Teagasc's table apply either way. When in doubt, ask your advisor and record the LPIS number.

Will a flood map stop me getting TAMS for a shed?

Not directly. TAMS needs planning permission or a declaration of exemption in place before you apply. The planning authority is the one that applies the flood zones, and farm buildings in Zone A face the Justification Test. Check the map before the engineer draws anything.

The bottom line

Sit down this week with agfood.ie on one screen and floodinfo.ie on the other. Mark every parcel by band. That list decides where stock go, where slurry does not, and where the next shed stands. An assistant can tidy the list and explain the legend. It cannot see your fields, and it should not pretend to.