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Serving St. Louis, MO and surrounding areas.

We are local to every home we install in. If you are in or around the St. Louis metro, we almost certainly cover you. Just ask.

Our service area

St. Louis, MO

Gateway Water Systems serves St. Louis city, St. Louis County, and the surrounding communities. We are not a national chain reading off a script. We install in this market every week and know its water.

If you are in the metro area and are not sure we cover your address, call us at (314) 723-6060. We almost certainly do.

Why local matters here

St. Louis water has its own profile.

Every market has its own water story, driven by geology, infrastructure age, and local treatment choices. Here is what shapes the St. Louis supply.

Limestone geology and hard water

The Mississippi and Missouri river valleys sit on thick limestone bedrock. St. Louis metro water runs consistently hard and often approaches 10 grains per gallon. The scale on your fixtures, the cloudy glassware, and the overworked water heater all trace back to that geology.

Chloramines from regional treatment

Missouri American Water uses chloramines, a blend of chlorine and ammonia, for disinfection. Unlike plain chlorine, chloramines do not cook off when you boil water. They leave a distinct chemical taste and smell that whole-home carbon filtration removes before water reaches any tap.

Older housing and infrastructure

A large share of St. Louis housing dates from before the 1986 federal ban on lead solder. Lead comes from these older pipes and service lines, not the treated supply, so it varies house to house. Under-sink reverse osmosis is the most reliable at-the-tap protection for drinking water.

Start with the data. Schedule a Free Water Assessment for your exact address and we will show you what is in your supply. No visit required.

See exactly what is in your water. Free.

No in-home visit, no obligation. We will send a personalized report on your home's water and an honest, all-in price if you want one.