SOURCES & DATA

Trust Begins with Knowing the Source

A sunlit stream. A clear path through the trees. Good information should offer the same feeling of clarity—with original sources you can explore for yourself.

Sunlit woodland stream flowing over rocks

OUR DATA PROVIDERS

Where every lookup comes from

Every air and water result on AirAndWater.win comes from these public sources. We show each result with its date and the source it came from.

U.S. EPA AirNow

What we use: Current Air Quality Index (AQI) readings and next-day forecasts for the nearest AirNow reporting area, from the official AirNow reporting-area file.
Who collects it: State, local and tribal air agencies, shared through EPA’s AirNow program.
How fresh: AirNow updates hourly. We check for a new file about every 10 minutes and show the observation hour with every reading.
Limits: Preliminary data, not yet verified, and may change. A reporting area covers a region, not your exact address. If none is within 25 miles, we show the closest one and say so.

Visit AirNow ↗

U.S. EPA ECHO (Safe Drinking Water records)

What we use: Active community water systems listed for your city or county: system name and ID, population served, water source, violations in the last three years, and the last inspection date.
Who collects it: States report to EPA’s Safe Drinking Water Information System (SDWIS); EPA publishes it through ECHO.
How fresh: EPA refreshes these records periodically. We show the date we retrieved them.
Limits: Historical compliance records, not live tap-water tests. A city or ZIP code cannot confirm which system serves your home; your water bill names your provider.

Visit EPA ECHO ↗

U.S. Census Bureau

What we use: The 2026 Gazetteer files (center points of U.S. cities, towns and ZIP code areas) and the Census Geocoder (state and county for a place).
Who collects it: The U.S. Census Bureau.
How fresh: Gazetteer files are published once a year; we use the 2026 edition.
Limits: We measure distances from a place’s center point, not your address. A Census ZIP code area (ZCTA) is close to, but not the same as, a USPS ZIP code.

Visit the Census Bureau ↗

Your approximate location

What we use: Cloudflare, our hosting provider, estimates your city from your internet connection so we can fill in the search box. “Use my location” uses your device’s location only if you allow it.
How fresh: Checked each time you open the page.
Limits: Network-based locations can be wrong, especially on a VPN or mobile network. Device locations are rounded to about 1 km. Neither is stored.

Read our Privacy Policy ↗

FOLLOW THE INFORMATION

Where our information begins

We help you understand and navigate information from public agencies; we are not the agency that collects or certifies those measurements.

EPA AirNow

A starting point for outdoor AQI observations, forecasts, reporting areas and relevant guidance.

Visit AirNow ↗

U.S. Environmental Protection Agency

Learn about drinking-water rules, reports, and public water system information.

Visit EPA ↗

Consumer Confidence Reports

Understand annual public drinking-water reporting and where to find your supplier’s report.

Explore CCRs ↗

State and local agencies

Regional departments and utilities may publish updated notices and information about your area.

How to find your provider

DATA WITH CONTEXT

Why dates, places, and limitations matter

A reporting area is not the same as your exact address, and a historical report is not a live reading.

Source

Find out who collected or published the information.

Time

Check the observation timestamp or reporting year.

Coverage

Understand the location, system, and population the result actually describes.

AN OPEN WINDOW, NOT A FALSE PROMISE

What we can and cannot tell you

We aim to help visitors reach authoritative information and understand it. Data may be delayed, incomplete, corrected, or unavailable; individual circumstances can differ from regional reports.