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Methodology

How we scored the Best Water Quality Reports in America 2026. Everything here is public so anyone can re-derive a score from the same sources.

Version 2026.1 · Published June 13, 2026 · By TapWaterData Editorial

What we measure, and what we don't

This is a ranking of the report, the document a resident receives, scored on how well it communicates water quality. It is not a ranking of the water itself, and a high score is not a safety claim. We judge utilities on communication because that is the gap the EPA's 2027 Consumer Confidence Report rule is built to close: clearer, more accessible, electronically delivered reports.

We read each utility's most recent published report page by page and scored it on five pillars, weighted as below. Scores are absolute against the rubric, not graded on a curve.

The five pillars

Plain-language clarity

25% of score

Can a non-expert actually read it?

5 / 5
Every term is translated, units are made tangible (e.g. an Olympic-pool analogy), and each section opens with what it means for you.
1 / 5
Unexplained acronyms and a reading level that assumes a chemistry background.

Contaminant transparency

25% of score

Do they show the numbers — including the bad news?

5 / 5
PFAS, lead and any exceedances are shown with real values against the limits, and problems are disclosed plainly rather than buried.
1 / 5
Bare compliance: a 'we meet all standards' line with the underlying numbers hidden or omitted.

Information design

20% of score

Is the data visual, or a wall of tables?

5 / 5
Contaminant data is visually encoded — charts against limits, multi-year trends, comparisons a layperson reads at a glance.
1 / 5
A raw regulatory table dump in default formatting with no visual hierarchy.

Digital accessibility & delivery

20% of score

Web-native, mobile, and lookup — or a buried PDF?

5 / 5
A responsive web-native report with navigation, charts, and an address lookup — not just a PDF.
1 / 5
A single PDF buried behind a landing page, or a broken/absent online version.

Timeliness & completeness

10% of score

Recent data, full panel.

5 / 5
The most recent data year, with a complete contaminant panel including unregulated/emerging compounds.
1 / 5
Stale data or a minimal panel that omits most of what was tested.

From sub-scores to a grade

Each pillar is scored 1–5. The weighted sum becomes a 0–100 report-clarity score, then a letter grade on fixed thresholds. Honorees (grade C and above) appear on the leaderboard with a tier. We publish honorees only — we do not print a public grade next to a utility that did not place, because the goal is to raise the floor, not to shame.

Letter grade
  • A90–100
  • B80–89
  • C70–79
  • D60–69
  • Fbelow 60
Honoree tier
  • Platinum90+
  • Gold80–89
  • Silver70–79

Which utilities we reviewed

The 2026 cohort is 25 utilities, weighted toward larger systems and reports with a reputation for design, plus a set of smaller utilities chosen to test the range. We judged the most recent published report for each. This is a first edition; the cohort will expand.

  • Philadelphia Water DepartmentPA
  • Mount Pleasant WaterworksSC
  • Tucson WaterAZ
  • DC WaterDC
  • Denver WaterCO
  • Greenville WaterSC
  • City of Grants PassOR
  • San Francisco Public Utilities CommissionCA
  • WSSC WaterMD
  • East Bay Municipal Utility DistrictCA
  • Austin WaterTX
  • Medford WaterOR
  • New York City DEPNY
  • Akron Water SupplyOH
  • City of Burlingame WaterCA
  • City of RichmondTX
  • Seattle Public UtilitiesWA
  • LADWPCA
  • San Jose WaterCA
  • Fayetteville PWCNC
  • Louisville WaterKY
  • San Diego Public UtilitiesCA
  • City of RedmondOR
  • Massachusetts Water Resources AuthorityMA
  • Honolulu Board of Water SupplyHI

Data sources

  • Each utility's own most recent published water quality report (CCR).
  • EPA Safe Drinking Water Information System (SDWIS).
  • The EPA 2027 CCR Rule revisions and peer-reviewed CCR-accessibility research, which anchor the rubric.

Independence, corrections, and AI

Independence

No utility paid for placement, and displaying a badge is free and does not affect rank. TapWaterData earns affiliate revenue from filter recommendations elsewhere on the site. That revenue is firewalled from this ranking, which judges utilities and recommends no products.

Corrections

Scores are drawn from public documents. Before we promote a utility's recognition, we offer them a chance to review the underlying detail. If any utility believes a score is based on an error, we review the source and correct it, and we date every change.

Use of AI

Reports were read and scored with editorial judgment. AI-assisted tools helped organize notes; every published score and claim was verified by a person against the source report.

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