The short version
- Every serious market built a number anyone can read. Water never got one. AquaScore™ gives it one: a rating from 0 to 100, with one word that says what was found.
- It's independent. We never sell water, filters or treatment, so nothing we rate is something we sell.
- Each contaminant is checked twice: against its legal limit and against the strictest published health benchmark. The distance between them is the AquaGap™.
- No data, no score. Where too little has been measured recently, the answer is "insufficient data," and the gaps are named.
- Every score names its method version, and every number behind it names its source and its date.
Every other product has a number
A bond has a rating. A borrower has a score. A cereal box has a label.
When a market can't see quality, it can't reward it. So every serious market built a number anyone can read. Lenders read a credit score. Investors read a bond rating. Shoppers read a Nutrition Facts label. Each one took something only experts could judge and made it public, comparable and impossible to ignore. Each one changed what got made.
| Year | The number |
|---|---|
| 1909 | Moody's® publishes its first bond ratings. |
| 1989 | The credit score gives lending one number. |
| 1994 | The Nutrition Facts label becomes required on packaged food. |
| 2026 | AquaScore™ rates the water. |
Water never got its number. The most essential product on earth still arrives with a yearly report, written for regulators, about water we drank months ago.
AquaScore™ gives water its number: one rating, from 0 to 100, for the water that reaches a place, with one word that says what was found. It's independent. We never sell water, filters or treatment, so nothing we rate is something we sell. We read the record, analyze it and tell you what to do. Where the data doesn't exist yet, Guardians collect it by testing.
Legal isn't always clean
The data exists. It's spread across federal files, state databases and utility reports, and almost nobody can read it. Four gaps stand between a family and an answer.
1. The law sets a floor
A system can meet every federal limit and still sit far from health benchmarks. In Atlanta, lead at the 90th percentile of home taps was 1.4 parts per billion in 2024: within the 15 ppb action level, and 7 times California's 0.2 ppb health goal. That distance is the AquaGap™.
2. The record is late
Families get one report a year, about last year's water. Federal files mostly record whether a system complied, not what it measured. The measurements live in state databases few people know exist.
3. The tests can't see far enough
"Not detected" doesn't mean "not there." Federal PFAS testing reports PFOA down to 4 parts per trillion. California's health goal is 0.007. A "not detected" result can hide a level up to 571 times that goal, and no one is told.
4. A ZIP isn't a water system
People search by address. Water is reported by utility. One ZIP code can draw from two or three systems, some buy water from others, and the Last Mile, your service line and your home's pipes, is tested almost nowhere.
No data, no score
A score built from missing data rewards the absence of measurement. So AquaScore™ refuses to guess. Where too little has been measured recently, the answer is "insufficient data," and the gaps are named.
Where enough is known, the answer is one number, one word, and every reading behind them, each with its source and its date. Anyone can check it, and that's what makes the score credible.
Every number, sourced
The method is published and versioned, and an independent science panel is forming to review it. This is version 2.1.0, in plain words.
Step 1. Find the water
Each ZIP code is matched to every water system that serves it, weighted by where people live, block by block, never by land area. A mail-only ZIP, like an airport's, goes to the system that serves the facility. Your address, not just your utility.
Step 2. Gather the record
EPA's national testing, the state's own sample-by-sample results and each utility's annual report. Every reading keeps its source, its date and the statistic it reports. A system that buys water inherits its supplier's source-water results, never its pipe results. Three layers, one record.
Step 3. Keep it fresh
A reading counts toward the score for a set window: one year for disinfection byproducts, three years for lead and PFAS. Anything older is shown as old record and left out of the score. At least half of 15 core contaminants must be fresh before any score publishes. Old data is shown, never scored.
Step 4. Measure twice
Each contaminant is checked against its enforceable legal limit and against the strictest published health benchmark. The distance between them is the AquaGap™. The health side drives the score; the legal side stands beside it. Legal and clean are two different numbers.
One number. One word.
Step 5. Combine: one bad actor can't hide
Each contaminant's level is divided by its health benchmark. The engine takes the worse of two numbers: the total across every contaminant, or the single worst one weighted by severity. Many clean results can never average away one serious one.
The score is 100 × e−K × hazard, with K set so a hazard of 30 scores 50. Past 10 times a benchmark, a contaminant's ratio is tempered on a log scale, so each tenfold step halves the score.
Step 6. Rate: five words, each one a fact
| Word | What it means |
|---|---|
| TRACE | Nothing we score was detected. |
| DETECTED | Measurable amounts, all at or below their health benchmarks. |
| ELEVATED | At least one contaminant above its health benchmark. |
| HIGH | At least one contaminant 10 times or more above its health benchmark. |
| SEVERE | At least one contaminant above its enforceable legal limit. |
- Three panels. Health, Legal and Areas of concern. Benchmarks not yet in the score are shown, never hidden, and never change the number.
- Blind spots. A non-detect from a test that can't reach the health level is listed as a blind spot, never scored as clean or as contaminated.
- No cliff to zero. Far past a benchmark, the score keeps falling by halves, never off a cliff. Only a detected germ such as E. coli forces a 0.
Atlanta, scored
The first public AquaScores™ were computed on October 15, 2026, from public records alone, for five ZIP codes in metro Atlanta: each matched block by block, drawn from 379 state sample records from 2025–26, with 11 of 15 core contaminants fresh, on method version 2.1.0.
City of Atlanta (GA1210001): 62 · ELEVATED. ZIPs 30303, 30313, 30320 and 30331. Partial record: 11 of 15 core contaminants measured within their windows. Newest sample Sept 21, 2026.
- Health. Lead, 1.4 ppb at the 90th percentile of home taps (2024): 7 times California's 0.2 ppb health goal. It drives the score.
- Legal. Within all federal legal limits. Trihalomethanes at 76% of the limit: 61.1 ppb, the highest 12-month location average in state samples through Sept 2026.
- Areas of concern. Trihalomethanes 407 times and haloacetic acids 440 times EWG's health guidelines. Shown, but not in the score until the independent science panel reviews them.
A neighboring metro Atlanta system: 15 · HIGH. PFOA averaged 3.6 parts per trillion across four quarterly EPA samples: within the 4 ppt legal limit, and 518 times the health benchmark. Far past the benchmark, but never a cliff to zero: the score falls by halves, and it tells this system apart from one at 5 times or 5,000.
Two rights, measured. AquaScore™ is the public-record measure behind the right to safety in the AquaRights Index™, and shows how much of the water is measured at all: the right to be informed. Both are published every year in The AquaRights Report™.
What a rating owes you
- Independence, or nothing. A rating is only worth what its independence is worth. We never sell water, filters or treatment, and no one can pay to change a score.
- Show the work. Every score names its method version, and every number behind it names its source and date. If a city, a reporter or a regulator can't check it, we haven't finished.
- What nobody measures is a finding. Missing tests, old records and tests that can't see far enough are reported as plainly as any result. Guardians who test year after year are how those gaps close.
Our commitments: a score people can stand behind, in any room.
- The method is published, and an independent science panel is forming to review every constant and limit.
- No utility, sponsor or customer sees or edits a score before it publishes.
- We never call water safe or unsafe. We say what was measured, against what, and when.
- Corrections are public, dated and kept on the record.
- We start with schools, then campuses, companies and cities.
Know your score
W.A.T.E.R. (We Are The Earth's Restorers): the same five steps, every score.
- W · Watch. Follow your address for changes.
- A · Assess the AquaGap™. See how far each result sits from its health benchmark.
- T · Test. Test at your own tap: the Last Mile.
- E · Equip. Choose a filter certified for what was found.
- R · Report. Share what you find with your community.
Water is not a political issue. It's a human issue.
Look up a ZIP at aquagenuity.com. Score your school. Become a Guardian. It's free.
Sources
- U.S. EPA, Public Water System Service Areas v3 (Mar. 2026).
- U.S. Census Bureau, 2020 ZCTA-to-block relationship file.
- U.S. EPA, UCMR 5 occurrence data.
- Georgia EPD, Drinking Water Watch (2025–26 samples).
- City of Atlanta Department of Watershed Management, 2025 Water Quality Report.
- California OEHHA, Public Health Goals.
- EWG Tap Water Database health guidelines.
- Aquagenuity AquaScore™ method v2.1.0, Oct. 15, 2026.
AquaScore™ describes what was measured or modeled against health benchmarks; it isn't a determination that water is safe or unsafe to drink. Moody's® is a registered trademark of Moody's Corporation. Aquagenuity isn't affiliated with, sponsored by or endorsed by them, EWG, EPA or any utility named here. AquaScore™, AquaGap™, AquaRights Index™ and The AquaRights Report™ are trademarks of Aquagenuity, Inc. Aquagenuity® is a registered trademark. All other marks belong to their respective owners. © 2026 Aquagenuity, Inc. · aquagenuity.com