City water guides
Know the water at home.
Source, treatment and mineral composition change from one supply to another. Explore five city guides, with utility reports and the details to read first.
NY
New York City
Reservoir sources, variable blends and building plumbing.
CALos Angeles
Several treatment sources, with different mineral profiles.
ILChicago
Lake Michigan supply and a separate question at the service line.
CASan Francisco
A varied source mix, chloramine and published mineral data.
FLMiami
Aquifer water, treatment plants and distinct service systems.
Read the whole profile
Four details.
Different questions.
Keep the source, units, reporting period and service area beside the numbers. A city average and a measurement at your tap describe different things.
| Detail | What it helps you understand | Where to look |
|---|---|---|
| Source and treatment | Where the supply begins and what happens before distribution. | The source map and treatment description. |
| Disinfectant | Which substance to name when comparing a filter claim. | The disinfectant or residual disinfectant row. |
| Hardness and minerals | Scale considerations and the mineral composition relevant to taste. | Hardness, calcium, magnesium and alkalinity rows. |
| Sampling and service area | Which water the result describes, and when it was measured. | The table headings, footnotes and supplier information. |