WaterCheck Ireland

Carrigtwohill Tap Water Quality

EPA monitoring records for Water Supply Zones mapped to Carrigtwohill contain 880 monitoring results across 71 parameters in 2025.

The separate EPA exceedance dataset contains 2 listed exceedance records across 1 parameter.

The most frequently listed parameter was Colony Count @ 22°C (2).

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
880Monitoring results
71Parameters tested
2EPA-listed exceedances
58Samples

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

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 median— ug/l
2025 maximum— ug/l
Measurements in 20255

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

4 numeric measurements available; 21 text-only records retained in JSON.

Nitrate

2025 median25.75
2025 maximum26.7
Measurements in 20255

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

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

E. coli

2025 median0
2025 maximum0
Measurements in 202541

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

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

Coliform Bacteria

2025 median0 100ml
2025 maximum0 100ml
Measurements in 202541

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

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

Fluoride

2025 median0.7
2025 maximum0.8
Measurements in 20255

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

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

Iron

2025 median30 ug/l
2025 maximum30 ug/l
Measurements in 202541

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

14 numeric measurements available; 205 text-only records retained in JSON.

Arsenic

2025 median—
2025 maximum—
Measurements in 20255

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

0 numeric measurements available; 25 text-only records retained in JSON.

2025880 results · 2 listed exceedances
Total results — independent scale
0 460.5 921 884 2021 861 2022 921 2023 838 2024 880 2025
Listed exceedances per 1,000 results — independent scale
0.000 2.323 4.646 1.131 2021 4.646 2022 2.172 2023 1.193 2024 2.273 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
2021884646611.131
2022861626644.646
2023921676722.172
2024838536711.193
2025880587122.273

Year-to-year detail

2025 compared with 2024

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

Results
2024838
2025880
+42
Listed exceedances
20241
20252
+1
Samples
202453
202558
+5
Parameters
202467
202571
+4

Parameters with EPA-listed exceedances

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

Colony Count @ 22°C

2 listed exceedance records / 36 tests5.56%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
300 1ml
Reported limit
100 1ml
Records with this unit/limit pair
2
Latest exceedance
02 Dec 2025

Across the year

When were listed exceedances recorded?

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

Colony Count @ 22°C02 Dec 2025
300 1mlReported result
100 1mlReported limit
GlashaboyWater supply
JanFebMarAprMayJunJulAugSepOctNovDecColony Count @ 22°C02 Dec 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Glashaboy; sample 2025/058628 Oct 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Glashaboy; sample 2025/1236

2 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.

Tibbotstown

68.65% geographic overlap with the Carrigtwohill Built Up Area.

Technical mapping details
EDEN code
0500PUB2408
Local authority
Cork
Page totals
Included
Spatial rank
1
Historical EPA scheme
Available
Latest monitoring year
2025
Glashaboy

28.08% geographic overlap with the Carrigtwohill Built Up Area.

Technical mapping details
EDEN code
0500PUB3303
Local authority
Cork
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.

71 parameter rows2 listed exceedance records58 samples
Show detailed data71 parameters · 2 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-dichloroethane5023 Sep 20252
2,3,6-trichlorobenzoic acid5023 Sep 20252
2,4-D5023 Sep 20252
Acrylamide5023 Sep 20252
Aluminium41002 Dec 20252
Ammonium5023 Sep 20252
Antimony5023 Sep 20252
Arsenic5023 Sep 20252
Atrazine5023 Sep 20252
Bentazone5023 Sep 20252
Benzene5023 Sep 20252
Benzo(a)pyrene5023 Sep 20252
Bisphenol A5023 Sep 20252
Boron5023 Sep 20252
Bromate5023 Sep 20252
Cadmium5023 Sep 20252
Chlorfenvinphos5023 Sep 20252
Chloride5023 Sep 20252
Chromium5023 Sep 20252
Clopyralid5023 Sep 20252
Clostridium Perfringens5023 Sep 20252
Coliform Bacteria41002 Dec 20252
Colony Count @ 22°C36202 Dec 20252
Colour41002 Dec 20252
Conductivity41002 Dec 20252
Copper5023 Sep 20252
Cryptosporidium14016 Dec 20252
Cyanide5023 Sep 20252
Cypermethrin5023 Sep 20252
Dichlobenil5023 Sep 20252
Dichlorprop5023 Sep 20252
Diflufenican5023 Sep 20252
Diuron5023 Sep 20252
E. coli41002 Dec 20252
Enterococci41002 Dec 20252
Fluoride5023 Sep 20252
Free Chlorine44002 Dec 20252
Giardia14016 Dec 20252
Glyphosate5023 Sep 20252
Haloacetic acids (Sum of 5 HAAs)5023 Sep 20252
Iron41002 Dec 20252
Isoproturon5023 Sep 20252
Lead5023 Sep 20252
Linuron5023 Sep 20252
Manganese5023 Sep 20252
MCPA5023 Sep 20252
Mecoprop5023 Sep 20252
Mercury5023 Sep 20252
Metaldehyde5023 Sep 20252
Microcystin-LR1015 Jul 20251
Nickel5023 Sep 20252
Nitrate5023 Sep 20252
Nitrite (at tap)5023 Sep 20252
Odour44002 Dec 20252
PAH5023 Sep 20252
Pendimethalin5023 Sep 20252
Pesticides - Total5023 Sep 20252
pH41002 Dec 20252
Propyzamide5023 Sep 20252
Selenium5023 Sep 20252
Simazine5023 Sep 20252
Sodium5023 Sep 20252
Sulphate5023 Sep 20252
Sum of PFAS (sum of 20)5023 Sep 20252
Taste44002 Dec 20252
Tetrachloroethene & Trichloroethene5023 Sep 20252
Total Chlorine44002 Dec 20252
Total Organic Carbon5023 Sep 20252
Triclopyr5023 Sep 20252
Trihalomethanes(Total)5023 Sep 20252
Turbidity (at tap)41002 Dec 20252

Showing 71 of 71 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
02 Dec 2025Colony Count @ 22°C3001ml100Glashaboy
0500PUB3303		2025/0586
28 Oct 2025Colony Count @ 22°C3001ml100Glashaboy
0500PUB3303		2025/1236

Common questions

Frequently asked questions

Is Carrigtwohill 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 Carrigtwohill?

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 Carrigtwohill?

In 2025, monitoring data for 2 Water Supply Zones mapped to Carrigtwohill included 880 results across 71 parameters. The separate EPA-listed exceedance dataset contains 2 records for those zones in 2025. These figures summarise historical records and are not a current safety verdict.

Who monitors drinking water quality in Carrigtwohill?

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 Carrigtwohill

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

MidletonCork · approximately 6.3 kmCobhCork · approximately 6.8 kmPassage West and MonkstownCork · approximately 7.6 kmCorkCork · approximately 12.9 kmCarrigalineCork · approximately 13.7 kmFermoyCork · approximately 25.3 km

Connected by mapped supply

Places sharing this Water Supply Zone

These published places share at least one Water Supply Zone used in this page's headline figures.

MidletonTibbotstownCobhGlashaboyCorkTibbotstown, Glashaboy

How this page is made

Sources and methodology

Settlement
Census 2022 Built Up Area: Carrigtwohill. 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