Water Quality
Dublin city and suburbs, Dublin
Latest available monitoring data: 2025
Environmental Protection Agency (EPA), Ireland / Uisce Éireann / Census 2022 Built Up Areas

Your local water data

Dublin city and suburbs Water Quality

A plain-language view of the latest available monitoring records for the Water Supply Zones mapped to Dublin city and suburbs.

Population (Census 2022)
1,263,219
Primary mapped zone
Fingal Zone 1
Primary zone geographic overlap
16.46%
CORE zones included
13

In 2025, monitoring data for Dublin city and suburbs included 30,281 results across 71 parameters.

The figures combine records from 13 CORE Water Supply Zones mapped to the Built Up Area. They describe zone-wide monitoring, including sampling locations outside the settlement.

Latest reporting year

2025 summary

30,281Test results
71Parameters tested
70Listed exceedances
8Parameters with exceedances

1,835 distinct zone/sample/date combinations. Monitoring dates: 06 Jan 2025 — 22 Dec 2025.

The separate EPA exceedance dataset lists 70 records for these zones in this reporting year. Result and exceedance totals are aggregated independently.

The short version

What should I know about Dublin city and suburbs water quality?

The figures describe the available historical records.

In 2025, monitoring data for Dublin city and suburbs included 30,281 results across 71 parameters.
8 parameters have listed exceedance records: Colony Count @ 22°C, Iron, Coliform Bacteria, Lead, Colour, Enterococci, Nickel, Turbidity (at tap).
Fingal Zone 1 is the zone with the largest mapped geographic overlap (16.46%). Overlap measures Built Up Area land area, not population or household supply.

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.

202530,281 results · 70 listed exceedances
Total results — independent scale
0 15,140.5 30,281 26,310 2021 28,311 2022 27,367 2023 26,199 2024 30,281 2025
Listed exceedances per 1,000 results — independent scale
0.000 1.156 2.312 0.494 2021 0.777 2022 1.754 2023 1.374 2024 2.312 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
202126,3102,07766130.494
202228,3112,01866220.777
202327,3671,70267481.754
202426,1991,60267361.374
202530,2811,83571702.312

Year-to-year detail

2025 compared with 2024

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

Results
202426,199
202530,281
+4,082
Listed exceedances
202436
202570
+34
Samples
20241,602
20251,835
+233
Parameters
202467
202571
+4

Reported records

Parameters with listed exceedances

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

Colony Count @ 22°C

26 listed exceedance records / 1,665 tests1.56%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
300 1ml
Reported limit
100 1ml
Records with this unit/limit pair
26
Latest exceedance
08 Dec 2025

Iron

19 listed exceedance records / 1,784 tests1.07%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
1,302 ug/l
Reported limit
200 ug/l
Records with this unit/limit pair
19
Latest exceedance
08 Dec 2025

Coliform Bacteria

10 listed exceedance records / 1,784 tests0.56%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
35 100ml
Reported limit
0 100ml
Records with this unit/limit pair
10
Latest exceedance
24 Nov 2025

Lead

8 listed exceedance records / 105 tests7.62%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
95 ug/l
Reported limit
10 ug/l
Records with this unit/limit pair
8
Latest exceedance
03 Sep 2025

Colour

3 listed exceedance records / 1,782 tests0.17%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
33 Hazen
Reported limit
20 Hazen
Records with this unit/limit pair
3
Latest exceedance
01 Dec 2025

Enterococci

2 listed exceedance records / 1,782 tests0.11%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
3 100ml
Reported limit
0 100ml
Records with this unit/limit pair
2
Latest exceedance
06 Oct 2025

Nickel

1 listed exceedance records / 106 tests0.94%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
40 ug/l
Reported limit
20 ug/l
Records with this unit/limit pair
1
Latest exceedance
03 Jun 2025

Turbidity (at tap)

1 listed exceedance records / 1,783 tests0.06%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
15.6 NTU
Reported limit
4 NTU
Records with this unit/limit pair
1
Latest exceedance
23 Jun 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°C08 Dec 2025
300 1mlReported result
100 1mlReported limit
Fingal Zone 1Water supply
JanFebMarAprMayJunJulAugSepOctNovDecColiform BacteriaColony Count @ 22°CColourEnterococciIronLeadNickelTurbidity (at tap)08 Dec 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 241698808 Dec 2025 — Iron: 318 ug/l; reported limit 200; DCC Zone 1; sample 241695202 Dec 2025 — Colony Count @ 22°C: 138 1ml; reported limit 100; Fingal Zone 1; sample 241459801 Dec 2025 — Colony Count @ 22°C: 145 1ml; reported limit 100; DLR Zone 1; sample 241397301 Dec 2025 — Colour: 33 Hazen; reported limit 20; DLR Zone 6; sample 241399501 Dec 2025 — Iron: 262 ug/l; reported limit 200; DLR Zone 6; sample 241399524 Nov 2025 — Coliform Bacteria: 1 100ml; reported limit 0; South Dublin Zone 2; sample 241116924 Nov 2025 — Iron: 326 ug/l; reported limit 200; DCC Zone 1; sample 241100718 Nov 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 240876917 Nov 2025 — Colony Count @ 22°C: 218 1ml; reported limit 100; Fingal Zone 1; sample 240817711 Nov 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 240588910 Nov 2025 — Coliform Bacteria: 2 100ml; reported limit 0; Fingal Zone 1; sample 240529703 Nov 2025 — Colony Count @ 22°C: 176 1ml; reported limit 100; Fingal Zone 1; sample 240232603 Nov 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 240233022 Oct 2025 — Coliform Bacteria: 5 100ml; reported limit 0; South Dublin Zone 4; sample 239851322 Oct 2025 — Iron: 208 ug/l; reported limit 200; South Dublin Zone 4; sample 239851321 Oct 2025 — Colony Count @ 22°C: 169 1ml; reported limit 100; Fingal Zone 1; sample 239791714 Oct 2025 — Coliform Bacteria: 1 100ml; reported limit 0; Fingal Zone 1; sample 239531507 Oct 2025 — Iron: 574 ug/l; reported limit 200; DLR Zone 8; sample 239275106 Oct 2025 — Coliform Bacteria: 1 100ml; reported limit 0; DLR Zone 6; sample 239225206 Oct 2025 — Colony Count @ 22°C: 188 1ml; reported limit 100; DLR Zone 6; sample 239224706 Oct 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; DLR Zone 6; sample 239225206 Oct 2025 — Enterococci: 1 100ml; reported limit 0; DLR Zone 1; sample 239224808 Sep 2025 — Iron: 219 ug/l; reported limit 200; DLR Zone 8; sample 238110303 Sep 2025 — Lead: 12 ug/l; reported limit 10; DCC Zone 4; sample 237943902 Sep 2025 — Coliform Bacteria: 11 100ml; reported limit 0; DLR Zone 6; sample 237881926 Aug 2025 — Coliform Bacteria: 35 100ml; reported limit 0; DCC Zone 4; sample 237594626 Aug 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; DCC Zone 3; sample 237594226 Aug 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; DCC Zone 3; sample 237624626 Aug 2025 — Enterococci: 3 100ml; reported limit 0; DCC Zone 4; sample 237594625 Aug 2025 — Coliform Bacteria: 5 100ml; reported limit 0; DCC Zone 3; sample 237532225 Aug 2025 — Coliform Bacteria: 1 100ml; reported limit 0; DCC Zone 3; sample 237555725 Aug 2025 — Colony Count @ 22°C: 104 1ml; reported limit 100; DCC Zone 3; sample 237531618 Aug 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 237230612 Aug 2025 — Iron: 244 ug/l; reported limit 200; DLR Zone 8; sample 237027812 Aug 2025 — Iron: 228 ug/l; reported limit 200; DLR Zone 8; sample 237027906 Aug 2025 — Lead: 95 ug/l; reported limit 10; DCC Zone 1; sample 236779006 Aug 2025 — Lead: 57 ug/l; reported limit 10; DCC Zone 2; sample 236748905 Aug 2025 — Colour: 22 Hazen; reported limit 20; DLR Zone 8; sample 236718305 Aug 2025 — Iron: 611 ug/l; reported limit 200; DCC Zone 6; sample 236721305 Aug 2025 — Iron: 642 ug/l; reported limit 200; DLR Zone 8; sample 236718307 Jul 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 235610107 Jul 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 235610307 Jul 2025 — Colony Count @ 22°C: 204 1ml; reported limit 100; Fingal Zone 1; sample 235610401 Jul 2025 — Iron: 262 ug/l; reported limit 200; DCC Zone 1; sample 235366224 Jun 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 235107423 Jun 2025 — Colour: 25 Hazen; reported limit 20; DCC Zone 1; sample 235026923 Jun 2025 — Iron: 1,302 ug/l; reported limit 200; DCC Zone 1; sample 235026923 Jun 2025 — Turbidity (at tap): 15.6 NTU; reported limit 4; DCC Zone 1; sample 235026918 Jun 2025 — Lead: 31 ug/l; reported limit 10; DCC Zone 3; sample 234856117 Jun 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; DCC Zone 3; sample 234806217 Jun 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 234798503 Jun 2025 — Nickel: 40 ug/l; reported limit 20; DLR Zone 1; sample 9070/2506028/0219 May 2025 — Colony Count @ 22°C: 149 1ml; reported limit 100; Fingal Zone 1; sample 233629819 May 2025 — Colony Count @ 22°C: 111 1ml; reported limit 100; Fingal Zone 1; sample 233629914 May 2025 — Lead: 60 ug/l; reported limit 10; DCC Zone 1; sample 233449612 May 2025 — Iron: 244 ug/l; reported limit 200; DCC Zone 1; sample 233291612 May 2025 — Iron: 246 ug/l; reported limit 200; DLR Zone 8; sample 233297912 May 2025 — Iron: 281 ug/l; reported limit 200; DLR Zone 8; sample 233298008 Apr 2025 — Coliform Bacteria: 1 100ml; reported limit 0; South Dublin Zone 2; sample 232125808 Apr 2025 — Colony Count @ 22°C: 167 1ml; reported limit 100; Fingal Zone 1; sample 232117907 Apr 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 232078207 Apr 2025 — Lead: 56 ug/l; reported limit 10; Fingal Zone 1; sample 232078626 Mar 2025 — Lead: 14 ug/l; reported limit 10; DCC Zone 1; sample 231676705 Feb 2025 — Lead: 17 ug/l; reported limit 10; DCC Zone 4; sample 229886227 Jan 2025 — Iron: 319 ug/l; reported limit 200; DCC Zone 6; sample 229529927 Jan 2025 — Iron: 366 ug/l; reported limit 200; DCC Zone 6; sample 229530327 Jan 2025 — Iron: 209 ug/l; reported limit 200; DCC Zone 6; sample 229530814 Jan 2025 — Colony Count @ 22°C: 140 1ml; reported limit 100; Fingal Zone 1; sample 229172506 Jan 2025 — Iron: 214 ug/l; reported limit 200; South Dublin Zone 4; sample 2288863

70 listed exceedance records across 8 parameters in 2025.

A closer look

Explore key parameters

Selected parameters with measurements in the displayed history window. Text-only and censored values remain unchanged.

Lead

Latest result0.24 ug/l
Latest sample16 Dec 2025
2025 median0.27 ug/l
2025 maximum95 ug/l
Reported limit10 ug/l
Tests in 2025105

8 listed exceedance records 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 resultListed exceedanceReported limit

328 numeric measurements available; 145 text-only records retained in JSON.

E. coli

Latest result0
Latest sample22 Dec 2025
2025 median0
2025 maximum0
Tests in 20251,784

0 listed exceedance records 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 resultListed exceedance

8,477 numeric measurements available; 0 text-only records retained in JSON.

Nitrate

Latest result2
Latest sample16 Dec 2025
2025 median3.39
2025 maximum11.68
Tests in 2025105

0 listed exceedance records 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 resultListed exceedance

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

Arsenic

Latest result0.21
Latest sample16 Dec 2025
2025 median0.26
2025 maximum0.57
Tests in 2025105

0 listed exceedance records 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 resultListed exceedance

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

Fluoride

Latest result0.63
Latest sample16 Dec 2025
2025 median0.67
2025 maximum0.79
Tests in 2025105

0 listed exceedance records 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 resultListed exceedance

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

Coliform Bacteria

Latest result0 100ml
Latest sample22 Dec 2025
2025 median0 100ml
2025 maximum35 100ml
Reported limit0 100ml
Tests in 20251,784

10 listed exceedance records 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 resultListed exceedanceReported limit

8,477 numeric measurements available; 0 text-only records retained in JSON.

Iron

Latest result21 ug/l
Latest sample17 Dec 2025
2025 median10 ug/l
2025 maximum1,302 ug/l
Reported limit200 ug/l
Tests in 20251,784

19 listed exceedance records 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 resultListed exceedanceReported limit

8,462 numeric measurements available; 16 text-only records retained in JSON.

Your mapped supply

Water supply

Every CORE zone is included. Geographic overlaps are reported separately and are not added together or weighted by population.

Fingal Zone 1

16.46% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
0900PUB1001
Local authority
Fingal
Mapping
CORE
Spatial rank
1
Historical EPA scheme
Available
Latest monitoring year
2025
SD_ZONE2

15.35% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
0800PUB1001
Local authority
South Dublin
Mapping
CORE
Spatial rank
2
Historical EPA scheme
Available
Latest monitoring year
2025
DCC ZONE 1 BALLYMORE

11.58% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
0700PUB1001
Local authority
Dublin City
Mapping
CORE
Spatial rank
3
Historical EPA scheme
Available
Latest monitoring year
2025
DCC ZONE 4 LEIXLIP BALLYMORE

6.50% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
0700PUB1005
Local authority
Dublin City
Mapping
CORE
Spatial rank
4
Historical EPA scheme
Available
Latest monitoring year
2025
DCC ZONE 6 BALLYMORE STILLORGAN

6.21% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
0700PUB1007
Local authority
Dublin City
Mapping
CORE
Spatial rank
5
Historical EPA scheme
Available
Latest monitoring year
2025
SD_ZONE4

5.80% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
0800PUB1004
Local authority
South Dublin
Mapping
CORE
Spatial rank
6
Historical EPA scheme
Available
Latest monitoring year
2025
DCC ZONE 3 LEIXLIP

5.73% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
0700PUB1004
Local authority
Dublin City
Mapping
CORE
Spatial rank
7
Historical EPA scheme
Available
Latest monitoring year
2025
DLR_ZONE8

5.64% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
1000PUB1008
Local authority
Dun Laoghaire-Rathdown
Mapping
CORE
Spatial rank
8
Historical EPA scheme
Available
Latest monitoring year
2025
DLR_ZONE6

5.45% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
1000PUB1006
Local authority
Dun Laoghaire-Rathdown
Mapping
CORE
Spatial rank
9
Historical EPA scheme
Available
Latest monitoring year
2025
DLR_ZONE1

3.75% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
1000PUB1001
Local authority
Dun Laoghaire-Rathdown
Mapping
CORE
Spatial rank
10
Historical EPA scheme
Available
Latest monitoring year
2025
DLR_ZONE7

3.59% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
1000PUB1007
Local authority
Dun Laoghaire-Rathdown
Mapping
CORE
Spatial rank
11
Historical EPA scheme
Available
Latest monitoring year
2025
DLR_ZONE2

3.40% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
1000PUB1002
Local authority
Dun Laoghaire-Rathdown
Mapping
CORE
Spatial rank
12
Historical EPA scheme
Available
Latest monitoring year
2025
DCC ZONE 2 BALLYBODEN

2.15% geographic overlap with the Dublin city and suburbs Built Up Area.

Technical mapping details
EDEN code
0700PUB1002
Local authority
Dublin City
Mapping
CORE
Spatial rank
13
Historical EPA scheme
Available
Latest monitoring year
2025

Common questions

About this water quality data

What do the figures for Dublin city and suburbs describe?

In 2025, monitoring data for Dublin city and suburbs included 30,281 results across 71 parameters. The figures combine records from 13 CORE Water Supply Zones mapped to the Built Up Area. They describe zone-wide monitoring, including sampling locations outside the settlement.

Which Water Supply Zones are included?

Fingal Zone 1; SD_ZONE2; DCC ZONE 1 BALLYMORE; DCC ZONE 4 LEIXLIP BALLYMORE; DCC ZONE 6 BALLYMORE STILLORGAN; SD_ZONE4; DCC ZONE 3 LEIXLIP; DLR_ZONE8; DLR_ZONE6; DLR_ZONE1; DLR_ZONE7; DLR_ZONE2; DCC ZONE 2 BALLYBODEN. Fingal Zone 1 is the zone with the largest mapped geographic overlap (16.46%). Overlap measures Built Up Area land area, not population or household supply.

What is a listed exceedance?

A record published in the separate Environmental Protection Agency (EPA), Ireland exceedance dataset. This page preserves those records and their reported values; it does not infer new exceedances from monitoring results.

Does geographic overlap tell me which water reaches my home?

No. The mapping compares settlement and supply-zone boundaries. It does not identify individual connections or the population served by each zone.

Do these records describe current conditions?

These are historical monitoring records, not a live supply notice or a current safety assessment. Consult Uisce Éireann for current supply information.

Why are some units or reported limits missing?

The monitoring results table does not supply units. Units and limits shown here come from the separate exceedance dataset when one consistent pair is available for the parameter and reporting period. Missing values do not mean there is no regulatory limit.

How are samples counted?

A sample is identified by its Water Supply Zone code, sample ID and sample date. A sample ID reused by another zone is counted separately. Results and exceedances are aggregated independently.

For closer inspection

Detailed data

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

71 parameter rows70 listed exceedance records1,835 samples
Show detailed data71 parameters · 70 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-dichloroethane105016 Dec 202513
2,3,6-trichlorobenzoic acid105016 Dec 202513
2,4-D105016 Dec 202513
Acrylamide105016 Dec 202513
Aluminium1,784017 Dec 202513
Ammonium105016 Dec 202513
Antimony105016 Dec 202513
Arsenic105016 Dec 202513
Atrazine105016 Dec 202513
Bentazone105016 Dec 202513
Benzene105016 Dec 202513
Benzo(a)pyrene105016 Dec 202513
Bisphenol A105016 Dec 202513
Boron105016 Dec 202513
Bromate105016 Dec 202513
Cadmium105016 Dec 202513
Chlorfenvinphos105016 Dec 202513
Chloride105016 Dec 202513
Chromium105016 Dec 202513
Clopyralid105016 Dec 202513
Clostridium Perfringens104016 Dec 202513
Coliform Bacteria1,7841022 Dec 202513
Colony Count @ 22°C1,6652616 Dec 202513
Colour1,782317 Dec 202513
Conductivity1,783017 Dec 202513
Copper105016 Dec 202513
Cryptosporidium49015 Dec 20251
Cyanide105016 Dec 202513
Cypermethrin105016 Dec 202513
Dichlobenil105016 Dec 202513
Dichlorprop105016 Dec 202513
Diflufenican105016 Dec 202513
Diuron105016 Dec 202513
E. coli1,784022 Dec 202513
Enterococci1,782222 Dec 202513
Fluoride105016 Dec 202513
Free Chlorine1,784022 Dec 202513
Giardia49015 Dec 20251
Glyphosate105016 Dec 202513
Haloacetic acids (Sum of 5 HAAs)3026 Nov 20252
Iron1,7841917 Dec 202513
Isoproturon105016 Dec 202513
Lead105816 Dec 202513
Linuron105016 Dec 202513
Manganese105016 Dec 202513
MCPA105016 Dec 202513
Mecoprop105016 Dec 202513
Mercury105016 Dec 202513
Metaldehyde105016 Dec 202513
Microcystin-LR59016 Dec 202511
Nickel106116 Dec 202513
Nitrate105016 Dec 202513
Nitrite (at tap)105016 Dec 202513
Odour1,638022 Dec 202513
PAH105016 Dec 202513
Pendimethalin105016 Dec 202513
Pesticides - Total105016 Dec 202513
pH1,783017 Dec 202513
Propyzamide105016 Dec 202513
Selenium105016 Dec 202513
Simazine105016 Dec 202513
Sodium105016 Dec 202513
Sulphate105016 Dec 202513
Sum of PFAS (sum of 20)104016 Dec 202513
Taste1,637022 Dec 202513
Tetrachloroethene & Trichloroethene105016 Dec 202513
Total Chlorine1,784022 Dec 202513
Total Organic Carbon105016 Dec 202513
Triclopyr105016 Dec 202513
Trihalomethanes(Total)105016 Dec 202513
Turbidity (at tap)1,783117 Dec 202513

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
08 Dec 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2416988
08 Dec 2025Iron318ug/l200DCC Zone 1
0700PUB1001		2416952
02 Dec 2025Colony Count @ 22°C1381ml100Fingal Zone 1
0900PUB1001		2414598
01 Dec 2025Colony Count @ 22°C1451ml100DLR Zone 1
1000PUB1001		2413973
01 Dec 2025Colour33Hazen20DLR Zone 6
1000PUB1006		2413995
01 Dec 2025Iron262ug/l200DLR Zone 6
1000PUB1006		2413995
24 Nov 2025Coliform Bacteria1100ml0South Dublin Zone 2
0800PUB1001		2411169
24 Nov 2025Iron326ug/l200DCC Zone 1
0700PUB1001		2411007
18 Nov 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2408769
17 Nov 2025Colony Count @ 22°C2181ml100Fingal Zone 1
0900PUB1001		2408177
11 Nov 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2405889
10 Nov 2025Coliform Bacteria2100ml0Fingal Zone 1
0900PUB1001		2405297
03 Nov 2025Colony Count @ 22°C1761ml100Fingal Zone 1
0900PUB1001		2402326
03 Nov 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2402330
22 Oct 2025Coliform Bacteria5100ml0South Dublin Zone 4
0800PUB1004		2398513
22 Oct 2025Iron208ug/l200South Dublin Zone 4
0800PUB1004		2398513
21 Oct 2025Colony Count @ 22°C1691ml100Fingal Zone 1
0900PUB1001		2397917
14 Oct 2025Coliform Bacteria1100ml0Fingal Zone 1
0900PUB1001		2395315
07 Oct 2025Iron574ug/l200DLR Zone 8
1000PUB1008		2392751
06 Oct 2025Coliform Bacteria1100ml0DLR Zone 6
1000PUB1006		2392252
06 Oct 2025Colony Count @ 22°C1881ml100DLR Zone 6
1000PUB1006		2392247
06 Oct 2025Colony Count @ 22°C3001ml100DLR Zone 6
1000PUB1006		2392252
06 Oct 2025Enterococci1100ml0DLR Zone 1
1000PUB1001		2392248
08 Sep 2025Iron219ug/l200DLR Zone 8
1000PUB1008		2381103
03 Sep 2025Lead12ug/l10DCC Zone 4
0700PUB1005		2379439
02 Sep 2025Coliform Bacteria11100ml0DLR Zone 6
1000PUB1006		2378819
26 Aug 2025Coliform Bacteria35100ml0DCC Zone 4
0700PUB1005		2375946
26 Aug 2025Colony Count @ 22°C3001ml100DCC Zone 3
0700PUB1004		2375942
26 Aug 2025Colony Count @ 22°C3001ml100DCC Zone 3
0700PUB1004		2376246
26 Aug 2025Enterococci3100ml0DCC Zone 4
0700PUB1005		2375946
25 Aug 2025Coliform Bacteria5100ml0DCC Zone 3
0700PUB1004		2375322
25 Aug 2025Coliform Bacteria1100ml0DCC Zone 3
0700PUB1004		2375557
25 Aug 2025Colony Count @ 22°C1041ml100DCC Zone 3
0700PUB1004		2375316
18 Aug 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2372306
12 Aug 2025Iron244ug/l200DLR Zone 8
1000PUB1008		2370278
12 Aug 2025Iron228ug/l200DLR Zone 8
1000PUB1008		2370279
06 Aug 2025Lead95ug/l10DCC Zone 1
0700PUB1001		2367790
06 Aug 2025Lead57ug/l10DCC Zone 2
0700PUB1002		2367489
05 Aug 2025Colour22Hazen20DLR Zone 8
1000PUB1008		2367183
05 Aug 2025Iron611ug/l200DCC Zone 6
0700PUB1007		2367213
05 Aug 2025Iron642ug/l200DLR Zone 8
1000PUB1008		2367183
07 Jul 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2356101
07 Jul 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2356103
07 Jul 2025Colony Count @ 22°C2041ml100Fingal Zone 1
0900PUB1001		2356104
01 Jul 2025Iron262ug/l200DCC Zone 1
0700PUB1001		2353662
24 Jun 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2351074
23 Jun 2025Colour25Hazen20DCC Zone 1
0700PUB1001		2350269
23 Jun 2025Iron1,302ug/l200DCC Zone 1
0700PUB1001		2350269
23 Jun 2025Turbidity (at tap)15.6NTU4DCC Zone 1
0700PUB1001		2350269
18 Jun 2025Lead31ug/l10DCC Zone 3
0700PUB1004		2348561
17 Jun 2025Colony Count @ 22°C3001ml100DCC Zone 3
0700PUB1004		2348062
17 Jun 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2347985
03 Jun 2025Nickel40ug/l20DLR Zone 1
1000PUB1001		9070/2506028/02
19 May 2025Colony Count @ 22°C1491ml100Fingal Zone 1
0900PUB1001		2336298
19 May 2025Colony Count @ 22°C1111ml100Fingal Zone 1
0900PUB1001		2336299
14 May 2025Lead60ug/l10DCC Zone 1
0700PUB1001		2334496
12 May 2025Iron244ug/l200DCC Zone 1
0700PUB1001		2332916
12 May 2025Iron246ug/l200DLR Zone 8
1000PUB1008		2332979
12 May 2025Iron281ug/l200DLR Zone 8
1000PUB1008		2332980
08 Apr 2025Coliform Bacteria1100ml0South Dublin Zone 2
0800PUB1001		2321258
08 Apr 2025Colony Count @ 22°C1671ml100Fingal Zone 1
0900PUB1001		2321179
07 Apr 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2320782
07 Apr 2025Lead56ug/l10Fingal Zone 1
0900PUB1001		2320786
26 Mar 2025Lead14ug/l10DCC Zone 1
0700PUB1001		2316767
05 Feb 2025Lead17ug/l10DCC Zone 4
0700PUB1005		2298862
27 Jan 2025Iron319ug/l200DCC Zone 6
0700PUB1007		2295299
27 Jan 2025Iron366ug/l200DCC Zone 6
0700PUB1007		2295303
27 Jan 2025Iron209ug/l200DCC Zone 6
0700PUB1007		2295308
14 Jan 2025Colony Count @ 22°C1401ml100Fingal Zone 1
0900PUB1001		2291725
06 Jan 2025Iron214ug/l200South Dublin Zone 4
0800PUB1004		2288863

Nearby places

Nearby place links are not available yet.

Methodology

Sources and definitions

Settlement
Census 2022 Built Up Areas. Population refers to the whole settlement.
Water Supply Zones
Uisce Éireann spatial boundary mapping, spatial_intersection_esri_2026.
Monitoring
Environmental Protection Agency (EPA), Ireland public water supply monitoring and separate exceedance datasets, 2021–2025.

CORE means a positive intersection covering at least 1% of the Built Up Area. SECONDARY covers 0.1% to below 1%; BOUNDARY_TOUCH covers positive areas below 0.1%. All mappings are retained; only CORE zones contribute to headline monitoring figures.

Geographic overlap is a share of land area, not population. Each zone's records are included once per settlement using its EDEN/EPA scheme code. Records may appear on more than one settlement page where the same zone serves a wider area; settlement totals must not be added to estimate a national total.

Listed exceedances come from a separate dataset. Descriptive frequency divides listed exceedance record counts by monitoring result record counts. It is not an official EPA compliance rate and does not establish that each listed record has a matching result in the monitoring dataset.

Medians and maxima use non-null numeric results. Censored text such as “< 0.1” is preserved and is not converted into a number. Multiple results on the latest date are described together; a representative record does not imply time order within that day. Reported limits are source values, not a regulatory reference directory.

The latest reporting year is determined from monitoring results for the mapped CORE zones. If there are no monitoring results, available exceedance years are used. Missing years are not invented as zero-result years.

Additional spatial intersections (2)

Retained for mapping transparency; excluded from primary monitoring totals.

ZoneEDENClassGeographic overlap
SD_ZONE10800PUB1002SECONDARY0.620119%
Dunboyne2300PUB1006BOUNDARY_TOUCH0.000558%