Public water-quality datasets
We use public water data, EPA-linked records, and utility reports to build each ZIP report.
Audit Methodology
How the BaseWater audit works
The audit combines local water data with the answers you give us about your home. The public methodology below explains how BaseWater sources water claims, how often we review them, and what we do not claim from public data alone.
Last reviewed May 22, 2026
ZIP-to-utility mapping
Each ZIP is matched to the utility we believe serves that area. This can change when new data comes in.
Home details
Your answers about symptoms, plumbing age, tap-water use, family risk, and filters help shape the score.
Install-area limits
BaseWater only offers home visits and installs in covered Tampa Bay ZIP codes. Outside that area, you may only see a short preview or waitlist.
What affects your score
This is not a lab test from your sink. It is a risk score based on your ZIP data and your home details.
1
Risk from the utility tied to your ZIP.
2
How much tap water your home uses and how long you have lived there.
3
Older plumbing, well water, and other home details.
4
Kids, pregnancy, and other higher-risk signs.
5
How much your current filter setup may miss.
What the audit does and does not do
What it does
- Shows the likely utility profile for your ZIP.
- Shows water flags above health goals when the data supports it.
- Adjusts the result based on your home and family.
- Helps you decide if a free home water test is worth booking.
What it does not do
- It does not replace a tap-level lab test at your home.
- It does not guarantee a specific contaminant level at your faucet.
- It does not promise installation outside active service ZIPs.
- It is a guide, not medical advice.
How we treat source quality
Official utility reports, EPA-linked records, and state or county sources carry the most weight. EWG health guidelines and other public aggregators help with context, but they do not replace primary utility reporting or a home-level water test.
Primary
Utility reports, EPA SDWIS, EPA UCMR, state and county records.
Context
EWG health-guideline context and public contaminant explanations.
Directional
Third-party aggregators used for discovery and cross-checking only.
How claims become public
Water touches health and safety, so BaseWater separates discovery notes from public claims. Stronger page copy only ships when the source trail can support it.
High-stakes contaminant claims need an official utility, EPA, SDWIS, UCMR, state, county, or clearly labeled EWG health-guideline source.
Aggregator-only findings can start a research thread, but they do not become public claims until a primary source or EWG context supports them.
Public utility data can describe a system or service area. It cannot prove the exact level at one faucet.
Medical, pregnancy, child-health, and risk-language claims stay qualified and point back to testing or professional guidance.
Source review cadence
The current source-review ledger tracks 69 water-data rows, with 64 public-source rows and 5 internal-only discovery rows held out of public contaminant pages.
Primary official rows
Reviewed quarterly or when a CCR, UCMR, SDWIS, or city page changes.
Needs row-level verification
Reviewed monthly until the exact official row, PWS ID, or report table is confirmed.
Directional context
Kept qualified and refreshed before stronger copy is published.
Internal discovery only
Not published as a source-backed public claim.
Last ledger review
May 22, 2026
Next source review
June 22, 2026
Rows needing tighter verification
23
Legal limit is not the same as a health goal
EPA legal limits and action levels are compliance standards for public systems. Health goals or health-guideline comparisons can be stricter. BaseWater labels those comparisons so homeowners can see the difference without confusing a health goal for a legal violation.