Water Reports / IL
Chicago tap water, decoded.
Source: Chicago Department of Water Management
Disinfectant
Chlorine
Hardness
Moderately hard
TDS
140–200 ppm
Watch items
3
What to know about Chicago water
- +Chicago has the largest inventory of lead service lines in the country, roughly 400,000, mostly in pre-1986 homes.
- +Lake Michigan source water is high quality, but treatment is conventional and the lake can taste earthy after algal activity in late summer.
- +Hardness is moderate, enough for visible scale on glass and fixtures over time.
Hardness detail: ~7–8 grains per gallon.
For your shower
Chlorine-treated, moderately hard water: a standard filter will reduce the chlorine, and the hardness is manageable. The shower itself is not Chicago's main issue.
For your glass
The lead service line is the story here. The city's water is clean at the plant; the last fifty feet of pipe between the main and many Chicago kitchens is lead. Point-of-use filtration rated for lead is the recommended answer until lines are replaced.
How we'd filter Chicago
For Chicago homes, the drinking-water priority is unambiguous: lead reduction at the point of use. Opus's sediment stage and RO membrane are engineered for exactly this class of contaminant, with remineralization to keep the water from tasting flat afterward.
Does Chicago really have lead pipes?
Yes, more than any other US city. Around 400,000 lead service lines connect older Chicago homes to water mains. The city is replacing them, but the program will take decades. Filtering at the tap is the practical answer in the meantime.
Is Chicago tap water safe to drink?
At the treatment plant, yes, it meets all federal standards. The risk is specific to homes with lead service lines or pre-1986 interior plumbing. Flushing the tap before first use helps; point-of-use filtration is the durable fix.
Why does Chicago water sometimes taste earthy?
Late-summer algal activity in Lake Michigan produces geosmin, an earthy-tasting compound that is harmless but noticeable at parts-per-trillion levels. Carbon filtration removes it completely.
More reports
Figures are drawn from each utility's most recent consumer confidence report and public statements. Water chemistry varies by season and neighborhood; your utility's annual report is the authoritative source for your address.