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Iowa Water Quality
Across the 6 cities we track in Iowa, 1 has a contaminant above an EPA limit, and 5 meet every limit.
6 cities with published data · verified against EPA legal limits
Exceed a health limit
Safe — stains/tastes
Safe to drink
Above the legal limit
These Iowa cities have a contaminant above the EPA limit. See each page for the number vs the limit and what to do.
Safe to drink
5 cities meet every EPA legal limit.
Iowa water quality explained
Across the 6 Iowa cities with published data, 1 has at least one contaminant above a EPA limit — that's 17% of the systems we track. The pattern is regional rather than random, which is exactly what you'd expect from a state where water quality follows geology, land use, and treatment age.
What's actually in Iowa water
The contaminants that show up most often above legal limits are Perfluorohexane sulfonate (PFHXS) (1 city). In practice, a handful recur because they share a source: disinfection byproducts (trihalomethanes and haloacetic acids) form when chlorine reacts with organic matter in surface water, while nitrate and arsenic trace to agricultural and geological sources respectively. The specific mix differs by city, so find yours in the lists above for the exact reading.
Two caveats worth stating plainly. First, hardness and water quality are different things: a city can have hard water that is perfectly safe, or soft water with a genuine contaminant problem, and we track them on separate pages. Second, "below the legal limit" means below a legally enforceable ceiling — it does not mean zero. Many utilities report traces of contaminants that never approach the limit, and some independent groups (most notably EWG) apply stricter health guidelines of their own. We show the legal-limit verdict here and let you decide how much headroom you want.
Frequently asked questions
Is Iowa tap water safe to drink?
1 of the 6 Iowa cities we track has at least one contaminant above a EPA limit — those specific systems warrant attention. The remaining 5 meet every limit. Check the specific city page for the exact contaminants and levels.
What contaminants show up most in Iowa water?
Across the systems we track, the most common exceedances in Iowa are Perfluorohexane sulfonate (PFHXS) (1 city). These are disinfection byproducts, industrial/agricultural contaminants, or naturally occurring substances depending on the region — read the individual city pages for the specific levels and which limits they exceed.
How is Iowa water quality measured?
Utilities test for a regulated set of contaminants and report the results against EPA legal limits (Maximum Contaminant Levels). We pull the latest published results and flag any contaminant detected above its legal limit, keeping aesthetic-only exceedances (stains and taste) clearly separate from genuine health exceedances.
What's the difference between a health limit and an "aesthetic" exceedance?
A health limit (EPA MCL) is a legally enforceable ceiling set to protect health — lead, arsenic, and disinfection byproducts fall here. An aesthetic exceedance is a parameter like iron, manganese, or total dissolved solids that affects taste, odour, or staining but is not a health risk. We separate the two so a city with rusty-looking water isn't mistaken for one with unsafe water.