TapMatch

St. Louis, Missouri

Missouri American Water St. Louis County / St. Charles County 2025 CCR (PWS MO6010716). Not the City of St. Louis Water Division. Hardness 164 ppm (range 82–164) and 150 ppm (range 60–150) on two labeled source columns. Chloramines 2.7 ppm (range 0.9–3.4). No Measure S-style residential softener ban turned up.

Cited chemistry for St. LouisA chart of numbers printed on the utility report, each labeled with its unit. Missing numbers are left off.Hardness (column 1)164 ppm (range 82–164)Hardness (column 2)150 ppm (range 60–150)Chloramines2.7 ppm (range 0.9–3.4)TTHMs47 ppb highest LRAA (range 2–46)HAA529 ppb highest LRAA (range 4–31)WQR
Cited numbers from the utility report. Length follows the printed value against a labeled scale — not a health ranking. If the report has no number, it is not on the chart.
  1. Hardness (column 1)164 ppm (range 82–164)
  2. Hardness (column 2)150 ppm (range 60–150)
  3. Chloramines2.7 ppm (range 0.9–3.4)
  4. TTHMs47 ppb highest LRAA (range 2–46)
  5. HAA529 ppb highest LRAA (range 4–31)

Best match for St. Louis

Salt-based water softener

No district prohibition on a brine drain turned up in the current file.

Two tall mineral tanks and a black brine tank of a salt-based water softener, plumbed with copper pipe in a garage.
Salt-based softener: two mineral tanks and a brine tank.

A salt-based softener is the thing that actually removes hardness. Size it from your grains and how much water you use, not bathroom count. It needs a drain.

Shop salt-based softeners

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Other options that still fit

  • Salt-free conditioner

    A salt-free conditioner changes how scale sticks. It does not soften. Soap and spots stay closer to untreated. No brine line.

    Shop salt-free conditioners

  • Whole-house catalytic carbon for chloramine

    Catalytic carbon with a chloramine claim (NSF/ANSI 42 for chloramine). Regular chlorine carbon is the wrong box.

    Shop catalytic carbon for chloramine

  • Under-sink reverse osmosis

    The under-sink RO we actually run is Cloud RO — NSF/ANSI 58, kitchen tap, not a whole-house tank. Check the exact listing if PFAS is why you are shopping. Shop Amazon first for under-sink RO, or buy Cloud direct. Waterdrop is a tankless option if you want that path. A certifier-listed pitcher is the cheap first step. Nobody is paying for a medical claim.

    Shop under-sink reverse osmosisBuy Cloud RO directShop Waterdrop reverse osmosisShop PFAS-listed pitchers

  • Test the tap first

    A homeowner kit is a start. It is not a state-certified lab. Use a certified lab when the decision is expensive.

    Shop water test kits

On the report

Water utility
Missouri American Water (St. Louis County / St. Charles County)
Hardness
Total hardness as CaCO3, 2025 — one source column 164 ppm (range 82–164), other source column 150 ppm (range 60–150). Two labeled columns, not a blend we invented. City of St. Louis Water Division hardness is not this file. — Missouri American Water 2025 Annual Water Quality Report (St. Louis County / St. Charles County)
Disinfectant
Chloramines in the distribution system 2.7 ppm (range 0.9–3.4), MRDL 4. Treatment-plant chloramines row prints 1.7 (range 1.7–3.5). Narrative says the water is treated with chloramines. — Missouri American Water 2025 Annual Water Quality Report (St. Louis County / St. Charles County)
Brine / salt to the sewer
No district prohibition found in current research. Searched Missouri American Water and St. Louis County / St. Charles County sewer pages and codes for a residential self-regenerating softener or brine-drain ban like LACSD Measure S. None turned up. City of St. Louis Water Division is a different PWS — ask the sewer agency on the bill before you cut a brine drain.

Also around here

Extra context besides the utility report and the chart above — geology, an unregulated table, or a published study. Not a second set of printed tap numbers.

Most of metro St. Louis County and St. Charles County drinking water is treated by Missouri American Water from the Missouri and Meramec rivers. The City of St. Louis Water Division is a different PWS and is not this file. No Measure S-style residential softener ban turned up on the county systems we searched. Ask the sewer agency on the bill before you cut a brine drain. This is not a legal opinion.

The 2025 report prints total hardness as two labeled source columns — 164 ppm (range 82–164) and 150 ppm (range 60–150). We do not invent a blend.

Chloramines in the distribution system 2.7 ppm (range 0.9–3.4). TTHMs 47 ppb highest LRAA. HAA5 29 ppb. Kitchen shopping stays the Cloud RO / Waterdrop path already used on other cities if a listing is why you are looking.

Sources

  1. 2025 Annual Water Quality Report (St. Louis County / St. Charles County) — Missouri American Water. Accessed 2026-09-09.

Updated September 9, 2026. A city file is chemistry we can cite plus the sewer rule. No invented detections.