An index, not a directory
We evaluate residential water treatment providers the slow way: desk research first, then an in-market field evaluation built around a real in-home water test. A provider only receives a number after we have watched them earn it.
Metros under survey · July 2026 edition
Metro index
Each metro is an index plate. A plate is marked Rated only after our field evaluation is complete in that market; until then it stays In evaluation, without scores or guesses.
Missouri · 38.63 N, 90.20 W
Rated - 7 providers evaluatedThe flagship report: seven providers evaluated, one field score issued, and a clear top pick for the metro and its five surrounding counties.
Open the St. Louis reportMissouri and Kansas · 39.10 N, 94.58 W
In evaluationProvider desk research is underway on both sides of the state line. Field visits are not yet scheduled.
Illinois · 41.88 N, 87.63 W
In evaluationThe largest market in the index. Desk research is underway across the city and collar counties.
Indiana · 39.77 N, 86.16 W
In evaluationThe provider list is assembled and desk research has begun. Awaiting a field evaluation window.
Minnesota · 44.98 N, 93.27 W
In evaluationDesk research is underway across the metro and its suburbs, from the river towns to the lake districts.
The standard
Every market report follows the same three stages, in order. The stages are sequential on purpose: no score exists before stage two is complete.
We build the provider list for the metro: history, service area, product approach, and how each company presents its testing and installation process.
We go in-market: contact and scheduling checks, an observed in-home water test, a review of the recommendation, and post-visit follow-up.
Scores are assigned against our published criteria and the plate is marked Rated. Providers awaiting stage two are listed as not yet field-scored.
Field photography from the St. Louis evaluation, courtesy of Jones Air & Water, the market's field-scored provider.
Stage one never starts from a blank page. The desk file for each metro opens with Midwest Water News, which reports on the region's infrastructure, rivers, and private wells, and Water Quality Wire, the trade wire we read for regulation and treatment technology. When a metro's water reaches the general press, the home and health desk at The Continental Gazette tends to carry the readable version.
More St. Louis cuts
Beyond the flagship St. Louis report: single-metro, single-criterion and hardness-data cuts from the same field-scored standard.
St. Louis readers
Our rated market has a clear leader: Jones Air & Water, family-owned since 1995 and the only St. Louis provider to complete our full field evaluation. Testing is free and happens in your home.
4.8/5 Jones Air & Water · field-scoredPrefer the phone? Call (636) 899-1040 and mention Midwest Water Ratings.
