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
Portlaoise Tap Water Quality
EPA monitoring records for Water Supply Zones mapped to Portlaoise contain 553 monitoring results across 68 parameters in 2025.
The separate EPA exceedance dataset contains no listed exceedance records for the mapped Water Supply Zones in 2025.
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 Zone
- Portlaoise PWS
- Geographic overlap
- 99.56%
The Portlaoise Built Up Area overlaps Portlaoise PWS across approximately 99.56% of its land area.
Monitoring results apply to the Water Supply Zone as a whole and may include sampling locations outside Portlaoise.
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 median0.5
2025 maximum0.6
Measurements in 20253
0 EPA-listed exceedances in 2025.
View parameter history
Nitrate
2025 median25.21
2025 maximum27.49
Measurements in 20253
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
E. coli
2025 median0
2025 maximum0
Measurements in 202533
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
Coliform Bacteria
2025 median0 100ml
2025 maximum0 100ml
Measurements in 202533
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
Fluoride
2025 median0.76 mg/l
2025 maximum0.77 mg/l
Measurements in 20253
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
Iron
2025 median2.75 ug/l
2025 maximum7.3 ug/l
Measurements in 202532
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
Arsenic
2025 median0.12
2025 maximum0.13
Measurements in 20253
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
Monitoring over time
5-year trends 2021–2025
Available years in the latest 5-calendar-year window. Monitoring volume and descriptive frequency use separate scales.
2025553 results · 0 listed exceedances
Total results — independent scale
Listed exceedances per 1,000 results — independent scale
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.
| Year | Results | Samples | Parameters | Listed exceedances | Per 1,000 results |
|---|---|---|---|---|---|
| 2021 | 456 | 30 | 64 | 0 | 0.000 |
| 2022 | 531 | 32 | 64 | 4 | 7.533 |
| 2023 | 522 | 31 | 65 | 1 | 1.916 |
| 2024 | 538 | 33 | 65 | 1 | 1.859 |
| 2025 | 553 | 33 | 68 | 0 | 0.000 |
Year-to-year detail
2025 compared with 2024
Changes describe dataset volumes only. The comparison uses the previous available year.
Results
2024538
2025553
Listed exceedances
20241
20250
Samples
202433
202533
Parameters
202465
202568
Parameters with EPA-listed exceedances
Values and limits are reproduced as reported. Different unit/limit pairs are shown separately.
No listed exceedance records are available for this reporting year.
Across the year
When were listed exceedances recorded?
Each point represents one listed exceedance record. Records on the same date remain separate.
No listed exceedance records to plot.
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.
Portlaoise PWS
99.56% geographic overlap with the Portlaoise Built Up Area.
Technical mapping details
Detailed data
The complete parameter and listed exceedance tables for the reporting year.
68 parameter rows0 listed exceedance records33 samples
Show detailed data68 parameters · 0 exceedance records
Complete parameter index
All parameters in 2025
| 1,2-dichloroethane | 3 | 0 | 17 Nov 2025 | 1 |
| 2,3,6-trichlorobenzoic acid | 3 | 0 | 17 Nov 2025 | 1 |
| 2,4-D | 3 | 0 | 17 Nov 2025 | 1 |
| Acrylamide | 3 | 0 | 17 Nov 2025 | 1 |
| Aluminium | 3 | 0 | 17 Nov 2025 | 1 |
| Ammonium | 3 | 0 | 17 Nov 2025 | 1 |
| Antimony | 3 | 0 | 17 Nov 2025 | 1 |
| Arsenic | 3 | 0 | 17 Nov 2025 | 1 |
| Atrazine | 3 | 0 | 17 Nov 2025 | 1 |
| Bentazone | 3 | 0 | 17 Nov 2025 | 1 |
| Benzene | 3 | 0 | 17 Nov 2025 | 1 |
| Benzo(a)pyrene | 3 | 0 | 17 Nov 2025 | 1 |
| Bisphenol A | 3 | 0 | 17 Nov 2025 | 1 |
| Boron | 3 | 0 | 17 Nov 2025 | 1 |
| Bromate | 3 | 0 | 17 Nov 2025 | 1 |
| Cadmium | 3 | 0 | 17 Nov 2025 | 1 |
| Chlorfenvinphos | 3 | 0 | 17 Nov 2025 | 1 |
| Chloride | 3 | 0 | 17 Nov 2025 | 1 |
| Chromium | 3 | 0 | 17 Nov 2025 | 1 |
| Clopyralid | 3 | 0 | 17 Nov 2025 | 1 |
| Clostridium Perfringens | 3 | 0 | 17 Nov 2025 | 1 |
| Coliform Bacteria | 33 | 0 | 15 Dec 2025 | 1 |
| Colony Count @ 22°C | 29 | 0 | 15 Dec 2025 | 1 |
| Colour | 33 | 0 | 15 Dec 2025 | 1 |
| Conductivity | 33 | 0 | 15 Dec 2025 | 1 |
| Copper | 3 | 0 | 17 Nov 2025 | 1 |
| Cyanide | 3 | 0 | 17 Nov 2025 | 1 |
| Cypermethrin | 3 | 0 | 17 Nov 2025 | 1 |
| Dichlobenil | 3 | 0 | 17 Nov 2025 | 1 |
| Dichlorprop | 3 | 0 | 17 Nov 2025 | 1 |
| Diflufenican | 3 | 0 | 17 Nov 2025 | 1 |
| Diuron | 3 | 0 | 17 Nov 2025 | 1 |
| E. coli | 33 | 0 | 15 Dec 2025 | 1 |
| Enterococci | 3 | 0 | 17 Nov 2025 | 1 |
| Fluoride | 3 | 0 | 17 Nov 2025 | 1 |
| Free Chlorine | 33 | 0 | 15 Dec 2025 | 1 |
| Glyphosate | 3 | 0 | 17 Nov 2025 | 1 |
| Haloacetic acids (Sum of 5 HAAs) | 3 | 0 | 17 Nov 2025 | 1 |
| Iron | 32 | 0 | 15 Dec 2025 | 1 |
| Isoproturon | 3 | 0 | 17 Nov 2025 | 1 |
| Lead | 3 | 0 | 17 Nov 2025 | 1 |
| Linuron | 3 | 0 | 17 Nov 2025 | 1 |
| Manganese | 3 | 0 | 17 Nov 2025 | 1 |
| MCPA | 3 | 0 | 17 Nov 2025 | 1 |
| Mecoprop | 3 | 0 | 17 Nov 2025 | 1 |
| Mercury | 3 | 0 | 17 Nov 2025 | 1 |
| Metaldehyde | 3 | 0 | 17 Nov 2025 | 1 |
| Nickel | 3 | 0 | 17 Nov 2025 | 1 |
| Nitrate | 3 | 0 | 17 Nov 2025 | 1 |
| Nitrite (at tap) | 3 | 0 | 17 Nov 2025 | 1 |
| Odour | 30 | 0 | 15 Dec 2025 | 1 |
| PAH | 3 | 0 | 17 Nov 2025 | 1 |
| Pendimethalin | 3 | 0 | 17 Nov 2025 | 1 |
| Pesticides - Total | 3 | 0 | 17 Nov 2025 | 1 |
| pH | 33 | 0 | 15 Dec 2025 | 1 |
| Propyzamide | 3 | 0 | 17 Nov 2025 | 1 |
| Selenium | 3 | 0 | 17 Nov 2025 | 1 |
| Simazine | 3 | 0 | 17 Nov 2025 | 1 |
| Sodium | 3 | 0 | 17 Nov 2025 | 1 |
| Sulphate | 3 | 0 | 17 Nov 2025 | 1 |
| Sum of PFAS (sum of 20) | 3 | 0 | 17 Nov 2025 | 1 |
| Taste | 30 | 0 | 15 Dec 2025 | 1 |
| Tetrachloroethene & Trichloroethene | 3 | 0 | 17 Nov 2025 | 1 |
| Total Chlorine | 33 | 0 | 15 Dec 2025 | 1 |
| Total Organic Carbon | 3 | 0 | 17 Nov 2025 | 1 |
| Triclopyr | 3 | 0 | 17 Nov 2025 | 1 |
| Trihalomethanes(Total) | 3 | 0 | 17 Nov 2025 | 1 |
| Turbidity (at tap) | 33 | 0 | 15 Dec 2025 | 1 |
Showing 68 of 68 parameters.
EPA exceedance dataset
Listed exceedances in 2025
Newest first. Sample IDs distinguish records that may otherwise look identical.
| Date | Parameter | Result | Unit | Reported limit | Water supply / EDEN | Sample ID |
|---|---|---|---|---|---|---|
| No listed exceedance records available. | ||||||
Common questions
Frequently asked questions
Is Portlaoise 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 Portlaoise?
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 Portlaoise?
In 2025, monitoring data for the Water Supply Zone mapped to Portlaoise included 553 results across 68 parameters. The separate EPA-listed exceedance dataset contains 0 records for those zones in 2025. These figures summarise historical records and are not a current safety verdict.
Who monitors drinking water quality in Portlaoise?
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 Portlaoise
Nearest published Built Up Areas, ordered by straight-line distance between Census reference points.
How this page is made
Sources and methodology
- Settlement
- Census 2022 Built Up Area: Portlaoise. 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.
Additional spatial intersections (1)
Retained for mapping transparency; excluded from primary monitoring totals.
| Zone | EDEN | Class | Geographic overlap |
|---|---|---|---|
| Meelick PWS | 1600PUB0005 | BOUNDARY_TOUCH | 0.061507% |