Safeswim: Auckland's Modelled Beach Water-Quality Forecasts and Overflow Alerts
This overview was generated with AI from the public sources listed below and checked against them before publication. It has not had a complete human fact-check — treat it as a starting point and follow the sources.
17 sourced claims on this page, none individually verified yet — turn on “Sources in the text” to see each one.
How this atlas is made · What “last verified” means · What “source-checked” means · The full record behind this page
For 22 years, weekly samples at Red Beach found 1 exceedance; targeted sampling found 4 in a day. Auckland's Safeswim now forecasts the risk, but it cannot close a beach.
what does this mean?
The strongest source is press reporting; no primary evaluation was located. It grades who did the looking — not how well the project went. All four grades →Part of 1001 Smart Cities — 1,216 documented projects · 🏙️ 9 more in Auckland · 💧 Water guide · 🌱 Environment projects
Safeswim is Auckland Council's public map of swimming risk. For two decades it published weekly samples that took up to 48 hours to analyse; after an independent review commissioned in October 2016, the council rebuilt it in November 2017 around models that predict faecal bacteria from rainfall, wind and tide. Each site shows a green or red pin, updated at least every 15 minutes, and when a sensor on Watercare's wastewater network detects an overflow, the nearby beach turns black for 48 hours. By the 2025/26 summer it covered 163 sites, and it now also serves Northland. A red pin is advice only: Safeswim says neither councils nor Surf Life Saving New Zealand have the authority to close beaches.
📊 Impact
Before launch, the programme team tested the model against sampling targeted at four rain events at eight beaches in March and April 2017: it classified 43 of 64 samples correctly (67%), against 7 of 64 (11%) for the old weekly monitoring, and detected 39 of 54 guideline exceedances, against 2 of 54; 16 of its 64 results were still false negatives. The same paper reports that weekly monitoring at Red Beach found 1 exceedance in 330 samples over 22 years, while targeted sampling found 4 in a single day after 6 mm of rain in November 2017. Safeswim puts its own accuracy at 85–93% since 2019, and its December 2025 announcement gave the previous summer 93%, with Auckland beaches suitable for swimming 84.5 per cent of the time; these are the operator's figures. The one consequence a source attaches to the data is repair work: in December 2021 long-term warnings at Titirangi, Wairau Outlet and Piha North Lagoon were lifted, and the mayor credited the Safe Networks programme of Auckland Council and Watercare, funded by the Water Quality Targeted Rate, with resolving the contamination at Titirangi and Wairau Outlet "alongside further SafeSwim monitoring". The investigative phase at Titirangi alone cost about $250,000, before repairs. No source measures whether the forecasts changed who swims or reduced illness.
🎓 Lesson
A forecast changes what a city knows faster than what it does. Safeswim's models exposed contamination that weekly sampling had missed for decades, but with no power to close a beach the consequence has to come from elsewhere: from pipe investigations and repairs, paid for by a separate rate, that lift warnings one beach at a time. The model also carries two costs a city should expect. It made Auckland incomparable: national bathing-water statistics leave the region out, because Auckland does not supply its sampling results to the national dataset and predicted data and field measurements are not comparable. And it depends on political trust: in December 2024 the mayor dismissed a red pin on the new harbour pool he had opened a week earlier as computer modelling "which can mean anything".
Sources
Show 4 more sourcesShow fewer
📅 How old is the evidence?
Two clocks, kept apart: when this entry’s sources were published, and what has happened to its record in the atlas. Documented span: since 2017. 7 of 9 sources carry a publication date, from 12 September 2017 to March 2026.
When the sources were published
- Newsroom · pressNewsroom — Swimming in a contaminant soup (12 Sep 2017)
- Water New Zealand · industry associationWater New Zealand — Safeswim: a sea change in assessing beach water quality risk (2018 Stormwater Conference)
- The Spinoff · pressThe Spinoff — Cheat Sheet: How safe is it to swim at Auckland’s beaches? (16 Feb 2018)
- 1News (TVNZ) · press1News — Auckland beaches get years-long swim safety warnings removed (Dec 2021) · updated 3 December 2021
- Newstalk ZB · pressNewstalk ZB — Auckland Mayor Wayne Brown kicks up a stink after waterfront pool declared unsafe for swimming (27 Dec 2024)
- Auckland Council · city governmentOurAuckland (Auckland Council) — Safeswim rolls out expanded beach and water-quality coverage for summer (Dec 2025)
- Massey University (Environmental Health Intelligence NZ) · researchEnvironmental Health Intelligence NZ (Massey University) — Faecal indicator bacteria at recreational bathing sites (March 2026)
Show your work What this page rests on and what it can’t tell you · all 17 claims with their sources · the forensic record
Evidence file · public beta 17 addressable claims, 9 source dossiers, one permanent baseline. The file is unreviewed — an AI-assisted structural migration, not a human or expert endorsement. Every revision keeps a permanent copy under revision history.
Inspect the claims, one by one — verbatim text, sources and caveats for all 17
The text below is copied verbatim from the published record. Each claim names the source dossiers that carry it; caveats stay attached to the claim they qualify.
clm-c6b60c8342c5f6c7
descriptive
Safeswim is Auckland Council's public map of swimming risk.
Sources carrying this claim
clm-0dc786058699c0de
quantitative
For two decades it published weekly samples that took up to 48 hours to analyse
Sources carrying this claim
clm-ef41a4b42961a6b8
quantitative
after an independent review commissioned in October 2016, the council rebuilt it in November 2017 around models that predict faecal bacteria from rainfall, wind and tide
Sources carrying this claim
clm-d1fb98df92c8e516
quantitative
Each site shows a green or red pin, updated at least every 15 minutes
Sources carrying this claim
clm-f46e947c31fd1094
quantitative
when a sensor on Watercare's wastewater network detects an overflow, the nearby beach turns black for 48 hours
Sources carrying this claim
clm-38551031211791b5
quantitative
By the 2025/26 summer it covered 163 sites, and it now also serves Northland.
Sources carrying this claim
clm-820679668647671f
descriptive
Safeswim says neither councils nor Surf Life Saving New Zealand have the authority to close beaches.
Sources carrying this claim
clm-3ac7ff15f8358fb4
quantitative
it classified 43 of 64 samples correctly (67%), against 7 of 64 (11%) for the old weekly monitoring, and detected 39 of 54 guideline exceedances, against 2 of 54; 16 of its 64 results were still false negatives
Sources carrying this claim
clm-6de313db8241ef4d
quantitative
weekly monitoring at Red Beach found 1 exceedance in 330 samples over 22 years, while targeted sampling found 4 in a single day after 6 mm of rain in November 2017
Sources carrying this claim
clm-df8e93c1d5ae4204
quantitative
Safeswim puts its own accuracy at 85–93% since 2019, and its December 2025 announcement gave the previous summer 93%, with Auckland beaches suitable for swimming 84.5 per cent of the time
Sources carrying this claim
clm-d52fdfe596991fdd
quantitative
in December 2021 long-term warnings at Titirangi, Wairau Outlet and Piha North Lagoon were lifted, and the mayor credited the Safe Networks programme of Auckland Council and Watercare, funded by the Water Quality Targeted Rate, with resolving the contamination at Titirangi and Wairau Outlet "alongside further SafeSwim monitoring"
Sources carrying this claim
clm-f918bbb65af17529
quantitative
The investigative phase at Titirangi alone cost about $250,000, before repairs.
Sources carrying this claim
clm-a6d3384165060fe8
descriptive
No source measures whether the forecasts changed who swims or reduced illness.
Sources carrying this claim
clm-86cb25c1926dbb3a
descriptive
Safeswim's models exposed contamination that weekly sampling had missed for decades
Sources carrying this claim
clm-4dd0e35d2458b5b1
descriptive
with no power to close a beach the consequence has to come from elsewhere: from pipe investigations and repairs, paid for by a separate rate, that lift warnings one beach at a time
Sources carrying this claim
clm-000c79a725ca25b8
descriptive
national bathing-water statistics leave the region out, because Auckland does not supply its sampling results to the national dataset and predicted data and field measurements are not comparable
Sources carrying this claim
clm-b0e44b48aacd66de
quantitative
in December 2024 the mayor dismissed a red pin on the new harbour pool he had opened a week earlier as computer modelling "which can mean anything"
Sources carrying this claim
Forensic record — source dossiers, gaps, hashes and the exact revision this page renders
This layer records what is known about each source, what is still missing, and the exact snapshot this page is rendering. A missing date, archive or hash stays visible as missing.
Awaiting operator and domain-expert review; publication of this revision implies neither.
sha256:67f5d89cefa7bf39420b6d41c50ee6d38a2e6d0bf2bb79a6da75c57d8599a442
- 17
- of 17 claims mapped
- 9
- source dossiers
- 4
- publication dates recorded
- 0
- archives linked
- 0
- exact locators
- 0
- content captures hashed
Governance facts carried by the record
- Operator
- Auckland Council (Healthy Waters and Flood Resilience), with Watercare's overflow sensors, Surf Life Saving New Zealand and health partners; water-quality models by DHI
- Actor types
- city-government, utility, regional-government, civil-society
- Funding model
- public
- Funding description
- Auckland Council; overflow sensors on Watercare's wastewater network; remediation through the Water Quality Targeted Rate. No programme budget located.
- Cost
- Not recorded
- Ownership
- Not recorded
- Decision rights
- Not recorded
- Exit conditions
- Not recorded
9 source dossiers
Safeswim — Frequently asked questions
- Stable source ID
src-c9860cc630991d7a- Publisher
- Name not classified · safeswim.org.nz
- Type / language
- web-page · language not classified
- Published
- Not recorded
- Updated
- Not recorded
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
The programme's own FAQ (2026 edition, which ranks the 2025/26 season). States that water quality is updated every 15 minutes from sampling, real-time rainfall, tide, wind and sunlight data and models; that an overflow sensor on Watercare's wastewater network automatically overrides the model with a black pin for 48 hours; that 'Neither Councils nor Surf Life Saving New Zealand have the authority to close beaches'; that accuracy, checked against sampling and 'overseen independently', has been 85–93% since 2019; and that forecasts cover only the Auckland and Northland regions.
Safeswim — About Safeswim
- Stable source ID
src-7213e7fdd89e36ee- Publisher
- Name not classified · safeswim.org.nz
- Type / language
- web-page · language not classified
- Published
- Not recorded
- Updated
- Not recorded
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
The programme's standing description: green pin (low risk) or red pin (high risk) depending on whether predicted water quality meets New Zealand guideline values, a black pin when a wastewater overflow is detected, predictions updated at least every 15 minutes from rainfall, wind and other data, and manual overrides by operational staff.
- Claims linked
Water New Zealand — Safeswim: a sea change in assessing beach water quality risk (2018 Stormwater Conference)
- Stable source ID
src-6dec4e89b2f01528- Publisher
- Name not classified · waternz.org.nz
- Type / language
- web-page · language not classified
- Published
- Not recorded
- Updated
- Not recorded
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
Conference paper by the programme team (Martin Neale and Andrew Schollum of Puhoi Stour, Kris Fordham of Civix, Nick Brown of Auckland Council). Records the October 2016 independent review, the February 2017 committee decision, the November 2017 switch to modelling, the DHI model built 2014–2016, the pre-launch comparison (model 43 of 64 correct, monitoring 7 of 64; 39 of 54 exceedances detected against 2; 16 false negatives), and Red Beach's 1 exceedance in 330 samples over 22 years against 4 in one day after 6 mm of rain.
Newsroom — Swimming in a contaminant soup (12 Sep 2017)
- Stable source ID
src-194213a00a8af691- Publisher
- Name not classified · newsroom.co.nz
- Type / language
- web-page · language not classified
- Published
- 2017-09-12
- Updated
- Not recorded
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
Reports the council committee's approval of the new Safeswim scheme, to launch on 1 November 2017; quotes the mayor that the public will be shocked by the figures and 'will demand to know what we are doing about it', and the committee chair that 'we are being more transparent'; states the scheme 'will not result in instant improvements in water quality'.
- Claims linked
The Spinoff — Cheat Sheet: How safe is it to swim at Auckland’s beaches? (16 Feb 2018)
- Stable source ID
src-a409097172ba65c9- Publisher
- Name not classified · thespinoff.co.nz
- Type / language
- web-page · language not classified
- Published
- 2018-02-16
- Updated
- Not recorded
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
Explainer after February 2018 storms: the Safeswim website, a partnership including Auckland Council and Watercare, launched in November with a three-level alert system covering 84 beaches and 8 freshwater locations; also says Milford Beach 'has been closed at least three times since Christmas'.
- Claims linked
- Background source; no baseline claim points here
1News — Auckland beaches get years-long swim safety warnings removed (Dec 2021)
- Stable source ID
src-02abc77da979cff7- Publisher
- Name not classified · 1news.co.nz
- Type / language
- web-page · language not classified
- Published
- 2021-12-02
- Updated
- 2021-12-03
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
Reports that long-term warnings at Titirangi, Wairau Outlet and Piha North Lagoon were lifted; quotes the mayor crediting the Safe Networks programme, funded by the Water Quality Targeted Rate, 'alongside further SafeSwim monitoring', and the Safeswim programme manager putting the Titirangi investigative phase at about $250,000, excluding repairs.
Newstalk ZB — Auckland Mayor Wayne Brown kicks up a stink after waterfront pool declared unsafe for swimming (27 Dec 2024)
- Stable source ID
src-58644bc3565dc22c- Publisher
- Name not classified · newstalkzb.co.nz
- Type / language
- web-page · language not classified
- Published
- 2024-12-27
- Updated
- Not recorded
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
Reports a second red pin at the new $500,000 Karanga Plaza pool days after the mayor opened it, the mayor's remark that Safeswim is based on computer modelling 'which can mean anything', and the council's reply that sampling results take about 48 hours while water quality changes faster.
- Claims linked
OurAuckland (Auckland Council) — Safeswim rolls out expanded beach and water-quality coverage for summer (Dec 2025)
- Stable source ID
src-5330aa3ada9d9aac- Publisher
- Name not classified · ourauckland.aucklandcouncil.govt.nz
- Type / language
- web-page · language not classified
- Published
- Not recorded
- Updated
- Not recorded
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
Council announcement for the 2025/26 summer: 16 new sites bring the total to 163 beaches, lagoons, streams and lakes with water-quality data; last summer Auckland beaches were suitable for swimming 84.5 per cent of the time and Safeswim achieved 93 per cent accuracy, its highest to date.
- Claims linked
Environmental Health Intelligence NZ (Massey University) — Faecal indicator bacteria at recreational bathing sites (March 2026)
- Stable source ID
src-a407985c218f89ca- Publisher
- Name not classified · ehinz.ac.nz
- Type / language
- pdf · language not classified
- Published
- Not recorded
- Updated
- Not recorded
- Source last checked
- No source-level check date
- Record last verified
- 2026-10-15
- Dossier created
- 2026-10-15
- Retrieved copy
- No local capture recorded
- Archive
- No archived copy linked
- Content hash
- No captured content hash
- Locator
- Descriptive only — not page/paragraph exact
Open the recorded source note
National surveillance factsheet by Massey University's Environmental Health Intelligence programme. States that the Auckland region is excluded from the national recreational-bathing analysis because it does not supply water quality sampling results to LAWA and 'field measurements and predicted data are not comparable'.
- Claims linked
Known limits of this file
- Publisher names and source languages have not yet been classified; domains are recorded without guessing.
- Existing source notes are descriptive locators, not page- or paragraph-exact citations.
- A missing archive, publication date or content hash is shown as null rather than inferred.
- The project-level evidence grade ranks the strongest source in the entry; it is not a truth score for every claim.
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📎 Cite this project
1001 Smart Cities (2026). “Safeswim: Auckland's Modelled Beach Water-Quality Forecasts and Overflow Alerts” — Auckland, New Zealand. The Smart City Atlas. https://1001smartcities.org/projects/auckland-safeswim/ (last verified 2026-10-15). Data: CC BY 4.0.
The underlying data is free to reuse with attribution — see the open data page.
