WaterCheck Ireland

Sligo Tap Water Quality

EPA monitoring records for Water Supply Zones mapped to Sligo contain 1,202 monitoring results across 69 parameters in 2025.

The separate EPA exceedance dataset contains 3 listed exceedance records across 1 parameter.

The most frequently listed parameter was Iron (3).

These are historical monitoring records and do not confirm the current status of water at a specific address. Current notices are maintained by Uisce Éireann.

Latest monitoring year
2025
Page updated
September 2026
Water Supply Zones
2
1,202Monitoring results
69Parameters tested
3EPA-listed exceedances
60Samples

Monitoring results apply to the Water Supply Zones as a whole and may include sampling locations outside Sligo.

Selected monitoring data

Key drinking water parameters

Parameters are shown when measurements are available. Text-only and censored values remain unchanged in the detailed history.

Lead

2025 median1
2025 maximum1
Measurements in 20257

0 EPA-listed exceedances in 2025.

View parameter history

Individual numeric measurements from 2021–2025. Text-only and censored results are retained in the history JSON and are not plotted as numbers.

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Numeric resultEPA-listed exceedance

2 numeric measurements available; 33 text-only records retained in JSON.

Nitrate

2025 median1.6
2025 maximum2.66
Measurements in 20257

0 EPA-listed exceedances in 2025.

View parameter history

Individual numeric measurements from 2021–2025. Text-only and censored results are retained in the history JSON and are not plotted as numbers.

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Numeric resultEPA-listed exceedance

15 numeric measurements available; 17 text-only records retained in JSON.

E. coli

2025 median0
2025 maximum0
Measurements in 202560

0 EPA-listed exceedances in 2025.

View parameter history

Individual numeric measurements from 2021–2025. Text-only and censored results are retained in the history JSON and are not plotted as numbers.

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Numeric resultEPA-listed exceedance

284 numeric measurements available; 0 text-only records retained in JSON.

Coliform Bacteria

2025 median0 100ml
2025 maximum0 100ml
Measurements in 202560

0 EPA-listed exceedances in 2025.

View parameter history

Individual numeric measurements from 2021–2025. Text-only and censored results are retained in the history JSON and are not plotted as numbers.

Open this chart to load the measurements.

Numeric resultEPA-listed exceedance

284 numeric measurements available; 0 text-only records retained in JSON.

Fluoride

2025 median0.7 mg/l
2025 maximum0.9 mg/l
Measurements in 20257

0 EPA-listed exceedances in 2025.

View parameter history

Individual numeric measurements from 2021–2025. Text-only and censored results are retained in the history JSON and are not plotted as numbers.

Open this chart to load the measurements.

Numeric resultEPA-listed exceedance

34 numeric measurements available; 1 text-only records retained in JSON.

Iron

2025 median28.5 ug/l
2025 maximum477 ug/l
Measurements in 202560

3 EPA-listed exceedances in 2025.

View parameter history

Individual numeric measurements from 2021–2025. Text-only and censored results are retained in the history JSON and are not plotted as numbers.

Open this chart to load the measurements.

Numeric resultEPA-listed exceedance

110 numeric measurements available; 174 text-only records retained in JSON.

Arsenic

2025 median1
2025 maximum1
Measurements in 20257

0 EPA-listed exceedances in 2025.

View parameter history

Individual numeric measurements from 2021–2025. Text-only and censored results are retained in the history JSON and are not plotted as numbers.

Open this chart to load the measurements.

Numeric resultEPA-listed exceedance

6 numeric measurements available; 29 text-only records retained in JSON.

20251,202 results · 3 listed exceedances
Total results — independent scale
0 601 1,202 1,089 2021 1,179 2022 912 2023 1,155 2024 1,202 2025
Listed exceedances per 1,000 results — independent scale
0.000 3.817 7.634 4.591 2021 7.634 2022 5.482 2023 6.926 2024 2.496 2025

This is our descriptive frequency: listed exceedance records divided by result records, multiplied by 1,000. It is not an official EPA compliance rate. Differences in sampling volume and parameters tested affect comparisons. A missing denominator is shown as unavailable.

Monitoring history by year
YearResultsSamplesParametersListed exceedancesPer 1,000 results
20211,089616454.591
20221,179616497.634
2023912486555.482
20241,155556586.926
20251,202606932.496

Year-to-year detail

2025 compared with 2024

Changes describe dataset volumes only. The comparison uses the previous available year.

Results
20241,155
20251,202
+47
Listed exceedances
20248
20253
-5
Samples
202455
202560
+5
Parameters
202465
202569
+4

Parameters with EPA-listed exceedances

Values and limits are reproduced as reported. Different unit/limit pairs are shown separately.

Iron

3 listed exceedance records / 60 tests5.00%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
477 ug/l
Reported limit
200 ug/l
Records with this unit/limit pair
3
Latest exceedance
28 Mar 2025

Across the year

When were listed exceedances recorded?

Each point represents one listed exceedance record. Records on the same date remain separate.

Iron28 Mar 2025
223 ug/lReported result
200 ug/lReported limit
Kilsellagh Public Water SupplyWater supply
JanFebMarAprMayJunJulAugSepOctNovDecIron28 Mar 2025 — Iron: 223 ug/l; reported limit 200; Kilsellagh Public Water Supply; sample 16879927 Feb 2025 — Iron: 477 ug/l; reported limit 200; Foxes Den Public Water Supply; sample 16510123 Jan 2025 — Iron: 311 ug/l; reported limit 200; Foxes Den Public Water Supply; sample 159316

3 listed exceedance records across 1 parameters in 2025.

Your mapped supply

Water supply

Every Water Supply Zone used for this page's headline figures is included. Geographic overlaps are reported separately and are not added together or weighted by population.

Foxes Den Public Water Supply

44.69% geographic overlap with the Sligo Built Up Area.

Technical mapping details
EDEN code
2700PUB2701
Local authority
Sligo
Page totals
Included
Spatial rank
1
Historical EPA scheme
Available
Latest monitoring year
2025
Kilsellagh Public Water Supply

40.64% geographic overlap with the Sligo Built Up Area.

Technical mapping details
EDEN code
2700PUB2706
Local authority
Sligo
Page totals
Included
Spatial rank
2
Historical EPA scheme
Available
Latest monitoring year
2025

Detailed data

The complete parameter and listed exceedance tables for the reporting year.

69 parameter rows3 listed exceedance records60 samples
Show detailed data69 parameters · 3 exceedance records

Complete parameter index

All parameters in 2025

All parameters with test results or listed exceedance records in the latest reporting year
1,2-dichloroethane7016 Oct 20252
2,3,6-trichlorobenzoic acid7016 Oct 20252
2,4-D7016 Oct 20252
Acrylamide7016 Oct 20252
Aluminium60011 Dec 20252
Ammonium7016 Oct 20252
Antimony7016 Oct 20252
Arsenic7016 Oct 20252
Atrazine7016 Oct 20252
Bentazone7016 Oct 20252
Benzene7016 Oct 20252
Benzo(a)pyrene7016 Oct 20252
Bisphenol A7016 Oct 20252
Boron7016 Oct 20252
Bromate7016 Oct 20252
Cadmium7016 Oct 20252
Chlorfenvinphos7016 Oct 20252
Chloride7016 Oct 20252
Chromium7016 Oct 20252
Clopyralid7016 Oct 20252
Clostridium Perfringens7016 Oct 20252
Coliform Bacteria60011 Dec 20252
Colony Count @ 22°C53011 Dec 20252
Colour60011 Dec 20252
Conductivity60011 Dec 20252
Copper7016 Oct 20252
Cyanide7016 Oct 20252
Cypermethrin7016 Oct 20252
Dichlobenil7016 Oct 20252
Dichlorprop7016 Oct 20252
Diflufenican7016 Oct 20252
Diuron7016 Oct 20252
E. coli60011 Dec 20252
Enterococci60011 Dec 20252
Fluoride7016 Oct 20252
Free Chlorine60011 Dec 20252
Glyphosate7016 Oct 20252
Haloacetic acids (Sum of 5 HAAs)7016 Oct 20252
Iron60311 Dec 20252
Isoproturon7016 Oct 20252
Lead7016 Oct 20252
Linuron7016 Oct 20252
Manganese7016 Oct 20252
MCPA7016 Oct 20252
Mecoprop7016 Oct 20252
Mercury7016 Oct 20252
Metaldehyde7016 Oct 20252
Microcystin-LR5016 Oct 20252
Nickel7016 Oct 20252
Nitrate7016 Oct 20252
Nitrite (at tap)7016 Oct 20252
Odour53011 Dec 20252
PAH7016 Oct 20252
Pendimethalin7016 Oct 20252
Pesticides - Total7016 Oct 20252
pH60011 Dec 20252
Propyzamide7016 Oct 20252
Selenium7016 Oct 20252
Simazine7016 Oct 20252
Sodium7016 Oct 20252
Sulphate7016 Oct 20252
Sum of PFAS (sum of 20)7016 Oct 20252
Taste53011 Dec 20252
Tetrachloroethene & Trichloroethene7016 Oct 20252
Total Chlorine60011 Dec 20252
Total Organic Carbon7016 Oct 20252
Triclopyr7016 Oct 20252
Trihalomethanes(Total)7016 Oct 20252
Turbidity (at tap)60011 Dec 20252

Showing 69 of 69 parameters.

EPA exceedance dataset

Listed exceedances in 2025

Newest first. Sample IDs distinguish records that may otherwise look identical.

All listed exceedance records in the latest reporting year
DateParameterResultUnitReported limitWater supply / EDENSample ID
28 Mar 2025Iron223ug/l200Kilsellagh Public Water Supply
2700PUB2706		168799
27 Feb 2025Iron477ug/l200Foxes Den Public Water Supply
2700PUB2701		165101
23 Jan 2025Iron311ug/l200Foxes Den Public Water Supply
2700PUB2701		159316

Common questions

Frequently asked questions

Is Sligo tap water safe to drink?

WaterCheck Ireland does not issue a current safe or unsafe verdict. This page presents historical monitoring data. Check Uisce Éireann for any current Boil Water or Do Not Consume notices affecting your address.

Can you drink tap water in Sligo?

WaterCheck Ireland provides historical drinking-water monitoring data, not a current safe or unsafe verdict. For current Boil Water or Do Not Consume notices, check your Eircode with Uisce Éireann.

What is the tap water quality in Sligo?

In 2025, monitoring data for 2 Water Supply Zones mapped to Sligo included 1,202 results across 69 parameters. The separate EPA-listed exceedance dataset contains 3 records for those zones in 2025. These figures summarise historical records and are not a current safety verdict.

Who monitors drinking water quality in Sligo?

The historical monitoring figures shown here come from drinking-water datasets published by the Environmental Protection Agency (EPA), Ireland. Uisce Éireann operates public water supplies and publishes current supply notices.

What is a Water Supply Zone?

A Water Supply Zone is a defined area supplied by a public drinking-water system. Monitoring records apply to the zone as a whole, so sampling locations can be outside the Census Built Up Area.

What does a listed exceedance mean?

It is a record published in the separate EPA exceedance dataset. WaterCheck Ireland reproduces those records and does not infer additional exceedances or turn the record count into a safety assessment.

How can I check current water notices for my Eircode?

Use your Eircode on the Uisce Éireann website to check current Boil Water and Do Not Consume notices. This page is based on historical monitoring data and is not a live notice service.

Explore nearby reports

Water Quality Near Sligo

Nearest published Built Up Areas, ordered by straight-line distance between Census reference points.

BallinaMayo · approximately 47.1 kmCastlebarMayo · approximately 70.9 kmBallybofey and StranorlarDonegal · approximately 73.7 kmRoscommonRoscommon · approximately 74.1 kmLongfordLongford · approximately 74.9 kmCavanCavan · approximately 79.4 km

How this page is made

Sources and methodology

Settlement
Census 2022 Built Up Area: Sligo. Population refers to the whole Built Up Area.
Supply mapping
Uisce Éireann Water Supply Zone boundaries are matched geographically to the settlement.
Monitoring
EPA monitoring results and the separate listed exceedance dataset, 2021–2025.
Interpretation
Geographic overlap measures land area, not population served; monitoring applies across the full supply zone.

Read the full methodologyView data sources