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

Your local water data

Swords Water Quality

A plain-language view of the latest available monitoring records for the Water Supply Zones mapped to Swords.

Population (Census 2022)
40,776
Primary mapped zone
Fingal Zone 1
Primary zone geographic overlap
95.78%

In 2025, monitoring data for Swords included 6,315 results across 68 parameters.

The figures combine records from 1 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

6,315Test results
68Parameters tested
22Listed exceedances
3Parameters with exceedances

389 distinct zone/sample/date combinations. Monitoring dates: 06 Jan 2025 — 09 Dec 2025.

The separate EPA exceedance dataset lists 22 records for these zones in this reporting year. Result and exceedance totals are aggregated independently.

The short version

What should I know about Swords water quality?

The figures describe the available historical records.

In 2025, monitoring data for Swords included 6,315 results across 68 parameters.
3 parameters have listed exceedance records: Colony Count @ 22°C, Coliform Bacteria, Lead.
Fingal Zone 1 is the zone with the largest mapped geographic overlap (95.78%). 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.

20256,315 results · 22 listed exceedances
Total results — independent scale
0 3,157.5 6,315 4,612 2021 4,606 2022 5,063 2023 5,016 2024 6,315 2025
Listed exceedances per 1,000 results — independent scale
0.000 1.742 3.484 0.217 2021 0.651 2022 1.185 2023 2.193 2024 3.484 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
20214,6123686610.217
20224,6063086430.651
20235,0633216561.185
20245,01633165112.193
20256,31538968223.484

Year-to-year detail

2025 compared with 2024

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

Results
20245,016
20256,315
+1,299
Listed exceedances
202411
202522
+11
Samples
2024331
2025389
+58
Parameters
202465
202568
+3

Reported records

Parameters with listed exceedances

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

Colony Count @ 22°C

19 listed exceedance records / 370 tests5.14%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
300 1ml
Reported limit
100 1ml
Records with this unit/limit pair
19
Latest exceedance
08 Dec 2025

Coliform Bacteria

2 listed exceedance records / 389 tests0.51%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
2 100ml
Reported limit
0 100ml
Records with this unit/limit pair
2
Latest exceedance
10 Nov 2025

Lead

1 listed exceedance records / 19 tests5.26%

Descriptive frequency of records, not an official compliance measure.

Highest listed result
56 ug/l
Reported limit
10 ug/l
Records with this unit/limit pair
1
Latest exceedance
07 Apr 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°CLead08 Dec 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 241698802 Dec 2025 — Colony Count @ 22°C: 138 1ml; reported limit 100; Fingal Zone 1; sample 241459818 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 240233021 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 239531518 Aug 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 237230607 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 235610424 Jun 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 235107417 Jun 2025 — Colony Count @ 22°C: 300 1ml; reported limit 100; Fingal Zone 1; sample 234798519 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 233629908 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 232078614 Jan 2025 — Colony Count @ 22°C: 140 1ml; reported limit 100; Fingal Zone 1; sample 2291725

22 listed exceedance records across 3 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 result< 0.1 ug/l
Latest sample09 Dec 2025
2025 median0.23 ug/l
2025 maximum56 ug/l
Reported limit10 ug/l
Tests in 202519

1 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

63 numeric measurements available; 11 text-only records retained in JSON.

E. coli

Latest result0 across 10 records
Latest sample09 Dec 2025
2025 median0
2025 maximum0
Tests in 2025389

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

1,649 numeric measurements available; 0 text-only records retained in JSON.

Nitrate

Latest result7.36
Latest sample09 Dec 2025
2025 median8.52
2025 maximum11.68
Tests in 202519

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

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

Arsenic

Latest result0.25
Latest sample09 Dec 2025
2025 median0.32
2025 maximum0.39
Tests in 202519

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

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

Fluoride

Latest result0.61
Latest sample09 Dec 2025
2025 median0.64
2025 maximum0.78
Tests in 202519

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

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

Coliform Bacteria

Latest result0 100ml across 10 records
Latest sample09 Dec 2025
2025 median0 100ml
2025 maximum2 100ml
Reported limit0 100ml
Tests in 2025389

2 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

1,649 numeric measurements available; 0 text-only records retained in JSON.

Iron

Latest result2–7 across 10 records
Latest sample09 Dec 2025
2025 median3
2025 maximum114
Tests in 2025389

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

1,632 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

95.78% geographic overlap with the Swords 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

Common questions

About this water quality data

What do the figures for Swords describe?

In 2025, monitoring data for Swords included 6,315 results across 68 parameters. The figures combine records from 1 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. Fingal Zone 1 is the zone with the largest mapped geographic overlap (95.78%). 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.

68 parameter rows22 listed exceedance records389 samples
Show detailed data68 parameters · 22 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-dichloroethane19009 Dec 20251
2,3,6-trichlorobenzoic acid19009 Dec 20251
2,4-D19009 Dec 20251
Acrylamide19009 Dec 20251
Aluminium389009 Dec 20251
Ammonium19009 Dec 20251
Antimony19009 Dec 20251
Arsenic19009 Dec 20251
Atrazine19009 Dec 20251
Bentazone19009 Dec 20251
Benzene19009 Dec 20251
Benzo(a)pyrene19009 Dec 20251
Bisphenol A19009 Dec 20251
Boron19009 Dec 20251
Bromate19009 Dec 20251
Cadmium19009 Dec 20251
Chlorfenvinphos19009 Dec 20251
Chloride19009 Dec 20251
Chromium19009 Dec 20251
Clopyralid19009 Dec 20251
Clostridium Perfringens18009 Dec 20251
Coliform Bacteria389209 Dec 20251
Colony Count @ 22°C3701909 Dec 20251
Colour389009 Dec 20251
Conductivity389009 Dec 20251
Copper19009 Dec 20251
Cyanide19009 Dec 20251
Cypermethrin19009 Dec 20251
Dichlobenil19009 Dec 20251
Dichlorprop19009 Dec 20251
Diflufenican19009 Dec 20251
Diuron19009 Dec 20251
E. coli389009 Dec 20251
Enterococci388009 Dec 20251
Fluoride19009 Dec 20251
Free Chlorine389009 Dec 20251
Glyphosate19009 Dec 20251
Haloacetic acids (Sum of 5 HAAs)2027 Feb 20251
Iron389009 Dec 20251
Isoproturon19009 Dec 20251
Lead19109 Dec 20251
Linuron19009 Dec 20251
Manganese19009 Dec 20251
MCPA19009 Dec 20251
Mecoprop19009 Dec 20251
Mercury19009 Dec 20251
Metaldehyde19009 Dec 20251
Nickel19009 Dec 20251
Nitrate19009 Dec 20251
Nitrite (at tap)19009 Dec 20251
Odour330009 Dec 20251
PAH19009 Dec 20251
Pendimethalin19009 Dec 20251
Pesticides - Total19009 Dec 20251
pH389009 Dec 20251
Propyzamide19009 Dec 20251
Selenium19009 Dec 20251
Simazine19009 Dec 20251
Sodium19009 Dec 20251
Sulphate19009 Dec 20251
Sum of PFAS (sum of 20)18009 Dec 20251
Taste330009 Dec 20251
Tetrachloroethene & Trichloroethene19009 Dec 20251
Total Chlorine389009 Dec 20251
Total Organic Carbon19009 Dec 20251
Triclopyr19009 Dec 20251
Trihalomethanes(Total)19009 Dec 20251
Turbidity (at tap)389009 Dec 20251

Showing 68 of 68 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
02 Dec 2025Colony Count @ 22°C1381ml100Fingal Zone 1
0900PUB1001		2414598
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
21 Oct 2025Colony Count @ 22°C1691ml100Fingal Zone 1
0900PUB1001		2397917
14 Oct 2025Coliform Bacteria1100ml0Fingal Zone 1
0900PUB1001		2395315
18 Aug 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2372306
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
24 Jun 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2351074
17 Jun 2025Colony Count @ 22°C3001ml100Fingal Zone 1
0900PUB1001		2347985
19 May 2025Colony Count @ 22°C1491ml100Fingal Zone 1
0900PUB1001		2336298
19 May 2025Colony Count @ 22°C1111ml100Fingal Zone 1
0900PUB1001		2336299
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
14 Jan 2025Colony Count @ 22°C1401ml100Fingal Zone 1
0900PUB1001		2291725

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.