Tucson Water
Tucson, Arizona
Tucson pairs the most rigorous monitoring story in the cohort with unusual candor — it volunteers far more testing than required and openly documents a violation most utilities would bury. The main thing holding it back is format: all of that lives in a polished PDF with no responsive online version.
Scored edition: 2024 Annual Water Quality Report - Main System AZ0410112 (2024 data). Tucson Water has since published its 2025 Annual Water Quality Report - Main System (2025 data), which was not scored.
- Corrected September 13, 2026: Each scorecard now names and links the exact report edition we scored, and notes any newer edition the utility has published. Some report links had pointed to pages that have since moved on to a newer edition.
- Corrected September 13, 2026: The scorecard said the report has no address lookup; it sends readers to the city's Water Quality Dashboard to see results for their address. Its screenshot caption described tens of thousands of voluntary samples a year; the report gives its voluntary sample and test counts without a time period, and the caption now quotes them.
- Corrected September 13, 2026: Verdicts that named one factor as the only thing holding a report back now name it as the main one, matching sub-scores in which more than one pillar is below 5.
- Corrected September 13, 2026: Mount Pleasant Waterworks' transparency score changed from 5 to 4, moving it from #2 to #5 (still Gold, now 80/100); Tucson Water, DC Water and Denver Water each move up one place. Its report prints its PFAS results, including PFOS at 6.6 ppt, in a table that gives no limits and says such compounds may not have health-based standards, without mentioning the EPA's 4 ppt limit that result is above. The top transparency score calls for results shown against the limits and problems disclosed plainly.
- Corrected September 13, 2026: Scores reviewed after these corrections and kept: Denver Water's transparency (5), because its 2026 report shows lead and PFAS results against the limits and explains its missed monitoring requirement plainly; San Francisco's transparency (4), matching other reports that give PFAS as a not-detected statement; Tucson Water's digital accessibility (2), the score every PDF-only report received; and Philadelphia's clarity (5). East Bay MUD's score is for the 2024-data report that was read, which its scorecard notes had already been replaced when the ranking was published.
What their report looks like
How it scored, pillar by pillar
Weighted across five pillars for a 83/100 overall. Each note explains why this report earned that score.
Plain-language clarity25% of score
Plain-language framing throughout; even the monitoring violation is explained in terms a resident can follow rather than regulatory shorthand.
A 5/5 looks like: Every term is translated, units are made tangible (e.g. an Olympic-pool analogy), and each section opens with what it means for you.
Contaminant transparency25% of score
Exceptional — 38,792 voluntary samples against 12,549 required, a plainly disclosed missed-monitoring violation naming all six parameters and how it was closed, and a stated policy of pulling any well with detectable PFOA or PFOS.
A 5/5 looks like: PFAS, lead and any exceedances are shown with real values against the limits, and problems are disclosed plainly rather than buried.
Information design20% of score
Clean, well-organized data presentation, though it stops short of the chart-against-the-limit visual encoding the very top reports use.
A 5/5 looks like: Contaminant data is visually encoded — charts against limits, multi-year trends, comparisons a layperson reads at a glance.
Digital accessibility & delivery20% of score
A polished but downloadable PDF — there is no responsive web-native report, and for results at an address it points readers to a separate city Water Quality Dashboard, which caps how usable the report itself is on a phone.
A 5/5 looks like: A responsive web-native report with navigation, charts, and an address lookup — not just a PDF.
Timeliness & completeness10% of score
A thorough panel; the voluntary-monitoring program makes it one of the most complete in the cohort.
A 5/5 looks like: The most recent data year, with a complete contaminant panel including unregulated/emerging compounds.
marks the cohort average across all 25 reviewed reports.
What it does best
- The most rigorous voluntary-monitoring story in the cohort: 38,792 voluntary samples against 12,549 required.
- Discloses a missed-monitoring violation in plain language, naming the six parameters and how it was closed.
- A standing policy of removing any well with detectable PFOA or PFOS — and it says so.
Where it falls short
It is a polished PDF, not a web-native report — there is no responsive online version, and the address lookup it points to lives on a separate city dashboard rather than in the report.
How it compares
Tucson Water's report ranks #2 of 25 reviewed utilities, with a report-clarity score of 83/100 against a cohort median of 69. That places it in the top 8%.
See the full leaderboardWhat even this report can't tell you
A report describes the water leaving the plant, not what reaches your tap — your building's plumbing is where lead usually enters.
See Tucson's water data
Tucson Water, display your badge
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