Photo: Eric Jones · CC BY-SA 2.0Low radon and steady ground in Blacklion; flooding isn’t measured here
Blacklion has no Hazard risk Grade: Irish places under 1,000 residents aren’t graded. The figures below are still its own.
What stands out about Blacklion’s hazards
From the EPA’s radon map, Geological Survey Ireland’s landslide map, the OPW’s flood relief schemes and our estimate of low-lying homes, below.
What Blacklion faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Low-lying homes
Radon
Landslides
Ground heights
Blacklion has no Hazard risk Grade
Each figure is placed among Irish towns as the grade would place it, without a letter.
Less sure: The low-lying figure is our estimate from ground heights and the river map, not an official flood map. It can show a town is low-lying; it can’t show a town is safe. No LiDAR here: the heights come from a 30 m satellite model, which reads roofs and trees as ground, so this town’s figure isn’t counted. A small place (167 homes): a few houses move the figure a lot.
How many of Blacklion’s homes stand low isn’t measured
Low-lying homes, a TownRatings estimate from OPW and Geological Survey Ireland LiDAR ground heights and the EPA’s river map: not an official flood map.
Flooding isn’t measured in Blacklion: no LiDAR survey covers its homes, and the measure needs 80% of them, so flood isn’t counted for or against it. That doesn’t mean it doesn’t flood.
A rougher estimate, mostly from a 30 m satellite model, puts about 63% of homes low beside Lough Macnean. That model reads roofs and trees as ground, so it misses low homes more often than it invents them.
Weather and flood warnings for Blacklion
Where to see the warnings in force, and what this page can’t count.
Met Éireann issues yellow, orange and red warnings for rain, wind and coastal flooding county by county; Blacklion is covered by County Cavan’s.
| Warning | What Met Éireann means by it |
|---|---|
| Yellow | Weather that isn’t unusual but can be dangerous in places: be aware. |
| Orange | Infrequent, dangerous weather that can put people and property at risk: be prepared. |
| Red | Rare, extremely dangerous weather: take action to protect yourself and your property. |
Met Éireann doesn’t publish an open archive of past warnings, so how often warnings have covered Blacklion can’t be counted here.
No OPW flood relief scheme protects Blacklion
The Office of Public Works’ completed flood relief schemes and the areas each one benefits (OPW open data, CC BY 4.0).
None of the OPW’s completed flood relief schemes has a benefiting area that takes in Blacklion’s homes. The OPW builds schemes where the risk to homes is greatest, so most towns have none.
No other place across County Cavan has an OPW flood relief scheme either.
| Town | Scheme | Designed for | Homes behind it | Away |
|---|---|---|---|---|
| Mullingar Westmeath | Mullingar Flood Relief Scheme | 1 in 100 | 0.2% | 92 km |
| Ballinasloe Galway | Ballinasloe (Derrymullen) Flood Relief Scheme | 1 in 100 | 3.2% | 109 km |
| Tullamore Offaly | Tullamore Flood Relief Scheme | 1 in 100 | 2.4% | 116 km |
| Duleek Meath | Duleek Flood Relief Scheme | 1 in 100 | 12% | 118 km |
| Laytown-Bettystown-Mornington-Donacarney Meath | Mornington Flood Relief Scheme | 1 in 100 | 9.1% | 124 km |
| Baile Chláir Galway | Clare River (Claregalway) Flood Relief Scheme | 1 in 100 | 7.9% | 127 km |
No home in Blacklion stands on landslide-prone ground
Geological Survey Ireland’s landslide susceptibility map (1:50,000), read at every home.
Homes on ground rated high or moderately high
Blacklion is among the 64% of Irish towns with no home on such ground.
GSI rates ground from low to high by its slope, soil and rock. Most Irish landslides are on steep upland slopes and peat after heavy rain; a town on flat ground has almost none.
High means the ground could slide under the right conditions, such as days of heavy rain on a steep, wet slope; it isn’t a forecast that it will.
GSI landslide susceptibility, high and moderately high classes, share of the town’s homes on mapped ground (CC BY 4.0).
Blacklion is in the lowest radon band
The EPA’s radon map: for each 10 km square, the estimated share of homes above the national reference level of 200 Bq/m³.
A square where 10% or more of homes are estimated above the reference level is a High Radon Area; 0% of Blacklion’s homes are in one. The map is an estimate by area: two neighbouring houses can differ a lot.
A test is the only way to know a home’s level: two detectors, left for three months in a living room and a bedroom.
EPA radon map of Ireland (10 km grid), averaged over the town’s homes (CC BY 4.0).
No EPA-licensed site within 5 km of Blacklion: the nearest is 6.7 km away
Factories, farms, power plants and waste sites that hold an EPA licence for their emissions, in Blacklion and around its centre.
| Site | Licence and activity | Away |
|---|---|---|
| Glenfarne Wood Products Limited | IPC licence | 6.7 km |
An EPA licence sets what a site may release to air, water and land; it doesn’t mark the site as an accident hazard.
Sites holding dangerous substances in bulk come under the COMAH (Seveso) rules, but the HSA’s list of them has no open licence, so upper- and lower-tier sites aren’t counted here.
Source: EPA registers of Industrial Emissions, IPC and waste licences, sites licensed on 31 October 2026; distances in a straight line from the town’s centre.
Get ready for what Blacklion faces
What to do, and what to ask before you move.
- Never walk or drive through floodwater: 30 cm of moving water can float a car.
- Move valuables, papers and medicines upstairs.
- Turn off gas, electricity and water if you’re told to.
- Test over three months, in a living room and a bedroom.
- Above 200 Bq/m³, a small sump and fan usually fixes it.
- The EPA sells radon test kits at radon.ie and lists registered contractors who fix high readings.
- Bring in or tie down bins, trampolines and anything the wind can lift.
- Keep away from coastal paths and piers while an orange or red warning is in force.
- Charge phones and keep a torch: fallen lines are the commonest storm damage.
- After the storm, report a fallen line to ESB Networks and keep well clear of it.
- Ask whether the home has ever flooded, and get a buildings insurance quote before you commit: flood cover isn’t always offered.
- Ask the seller or landlord for a radon test result, or test in your first months there.
- Check the address on floodinfo.ie: the OPW’s flood maps and its record of past floods.
What this data can and can’t tell you
- An estimate, not a flood map. Low-lying homes is a TownRatings modelling step: each home’s ground height from LiDAR, against the level of the nearest big river (Strahler order 5 or more), lake or estuary within 1 km, or the sea within 2 km. A home within 5 m of the water’s level, or below 4 m near the sea, counts.
- Flood counts only one way. A high share of low-lying homes lowers the Hazard risk Grade; a low share never raises it, because defences, small streams, culverts, groundwater and flash floods don’t show in ground heights. Below the national median a town scores as the median.
- Defences aren’t counted. Flood defences aren’t taken off: the OPW scheme that protects the most homes is shown instead, with its design standard.
- Measured where the heights are detailed. A town is measured, and counted, only where 80% of its homes stand on LiDAR heights. Elsewhere the page says flooding isn’t measured, never that the town is dry.
- Radon is an estimate by area. The EPA’s radon map gives the estimated share of homes above 200 Bq/m³ for each 10 km square, averaged here over the town’s homes. It says where to test, not what one house holds.
- The sea is measured by height. Homes count as low by the sea when their ground is under 4 m and within 2 km of coastal or estuary water; waves, surges and erosion aren’t modelled.
- Landslide ground is a map of where slides could start. GSI’s susceptibility map rates the ground itself; it doesn’t record past slides or say when one will happen.
- Bathing water is rated season by season. The EPA classes each identified bathing water from four seasons of samples; a rating says how clean the water has been, not how safe it is to swim.
- One town, many streets. Risk is street by street. Check a specific address on floodinfo.ie before you buy or rent.
Check any address against the OPW’s official flood maps on floodinfo.ie
Questions about flooding and hazards in Blacklion
Does Blacklion flood?
For a single address, the OPW’s official flood maps and past floods are on floodinfo.ie.
Is radon a problem in Blacklion?
The EPA’s map estimates that about 0.3% of homes around Blacklion are above the radon reference level of 200 Bq/m³: a lower share than in 89% of Irish towns. 0% of its homes are in a High Radon Area. The only way to know a house is a three-month test.
Is Blacklion at risk of landslides?
No home in Blacklion stands on ground rated high or moderately high for landslides.
Flood: TownRatings’ estimate from ground heights, not an official flood map. Contains Irish Public Sector Data (Geological Survey Ireland, the Office of Public Works and the EPA) licensed under CC BY 4.0; Copernicus DEM © DLR e.V. and © Airbus, provided under COPERNICUS by the EU and ESA; © OpenStreetMap contributors. Radon and bathing water: EPA (CC BY 4.0). Landslide susceptibility: Geological Survey Ireland (CC BY 4.0).
Sources: low-lying homes: TownRatings’ estimate from GSI and OPW LiDAR, Copernicus GLO-30 and the EPA river network · radon: EPA radon map · landslides: GSI landslide susceptibility · industrial sites: EPA licence registers. Under Creative Commons Attribution 4.0 (CC BY 4.0).
Contains Central Statistics Office (CSO) data, Census 2022, and Tailte Éireann boundaries (CSO Urban Areas, Small Areas, local electoral areas, constituencies), under Creative Commons Attribution 4.0 (CC BY 4.0).