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Is Joliet Water Safe to Drink?
City of Joliet Department of Public Utilities · 2011 data · official source
This is the safety page for Joliet — how hard the water is (and what that costs) lives on the Joliet water hardness page · see how Joliet compares across all of Illinois on the Illinois hardness guide · or browse every Illinois city by safety status on the Illinois water quality page.
Joliet water meets all EPA legal limits. Each of the 2 tested contaminants below sits under its limit — most by a wide margin.
The one real caveat: lead and copper usually enter from a home's own plumbing, not the treated supply. If your home was built before the mid-1950s, older service lines and solder are the thing to check — not the water coming out of the treatment plant.
Note: independent health group EWG flags 2 detected contaminant(s) as above its own much-stricter voluntary benchmark — shown in the table below as informational only, not a safety claim. Every one sits below the legal EPA limit.
Why it's safe
- ✓ Continuous monitoring — City of Joliet Department of Public Utilities tests the water around the clock for microbiological safety and routinely for chemical parameters.
- ✓ Regulated to EPA limits — enforced under EPA National Primary Drinking Water Regulations.
- ✓ Disinfected — chlorine keeps the supply safe from bacteria from the treatment plant to your tap.
What's in Joliet's water
Detected contaminants reported for Joliet (EPA system ID IL1970450).
Source: EWG tap water database (Aug 2026).
Every detected contaminant is below the health limit. Some are still above EWG's stricter voluntary health benchmarks — common nationwide, shown below.
How to read this table: the legal limit (the EPA's Maximum Contaminant Level (MCL)) is the enforceable safety line — it's what regulators actually require. The EWG guideline column is a much stricter, voluntary health benchmark (often 100–1000× lower than the legal limit). Many contaminants sit below the legal limit but above the EWG line — that's common nationwide and means the water is still legally safe, not that it's dangerous.
| Contaminant | Typical level | EPA legal limit | EWG guideline | Status |
|---|---|---|---|---|
| Arsenic | 1.06 ppb | 10 ppb | 0.004 ppb | Below limit |
| Radium, combined (-226 and -228) | 1.53 pCi/L | 5 pCi/L | 0.05 pCi/L | Below limit |
Levels are system-wide utility averages. The legal limit is the EPA's Maximum Contaminant Level (MCL). EWG also flags 2 contaminant(s) as exceeding its own stricter (non-legal) health guideline — shown as an informational note only, not a safety claim.
Not sure what these levels mean for your health? Read our complete contaminants guide — what's detected vs. what matters, and how to read the numbers.
What actually matters in Joliet's water
Most of the numbers in the table are below the legal limit and aren't worth your worry. Here's the honest read on the ones people actually ask about in Joliet:
Why the limit exists: Arsenic is a Group 1 human carcinogen (IARC). The limit is based on increased risk of bladder, lung, and skin cancer, plus skin damage and circulatory problems at elevated long-term exposure.
Source: EPA MCL / HC MAC
Why the limit exists: Radium is radioactive; long-term exposure is associated with an increased risk of bone cancer.
Source: EPA MCL
Where Joliet's water comes from — and how it's treated
Groundwater (deep sandstone wells)
Like every U.S. municipal supply, Joliet's water is disinfected and monitored against EPA National Primary Drinking Water Regulations, published annually in the Consumer Confidence Report (CCR). If you want to read the raw report for yourself, our how to read your water quality report guide walks you through it line by line.
"My Joliet water tastes or smells like chlorine — is it still safe?"
Yes. A chlorine taste or smell doesn't mean the water is unsafe — it's the residual disinfectant doing its job (preventing bacteria from re-growing between the treatment plant and your tap). Seasonal changes, disinfection byproducts, or your own plumbing can all shift taste without affecting safety. If the taste bothers you, a simple activated-carbon pitcher filter removes it without any safety concern — the water was already safe before you filtered it.
Water quality vs. water hardness — don't confuse the two
"Water quality" (is it safe to drink) and "water hardness" (how much scale it leaves) are entirely different things — and confusing them leads to bad purchases. Joliet's water is very hard (17.53 GPG), which has no bearing on its safety — hardness is a cosmetic and appliance concern, not a health one. For what that hardness costs you in scale, appliance wear, and water-heater efficiency, see the Joliet water hardness page.
If contaminants concern you — add a drinking-water filter
Should you filter Joliet's water?
The softener handles hardness; a drinking-water filter removes Arsenic and removes Radium — if Joliet's reported levels concern you. EPA: Arsenic is a known human carcinogen (skin, lung, bladder cancer) and, at exposure, is also linked to cardiovascular disease and developmental effects. EPA MCL: 10 ppb. EPA: Radium is radioactive and long-term exposure is associated with an increased risk of bone cancer and other effects. For a full breakdown of what each filter type removes, see best whole-house water filters.
We may earn a commission when you buy through links on our site. This doesn't affect our recommendations. Full disclosure.
When to call a professional
Joliet's water meets every legal limit, so there's nothing that requires a pro — but clean, good-tasting water is always worth a little peace of mind, and your home's plumbing is its own variable. The clearest reason to call a licensed plumber: if your home was built before the mid-1950s and may still have lead service lines or solder — the lead risk lives in your pipes, not the city's water. Beyond that, a professional can test your tap (not just the city-wide report) and tell you honestly whether any treatment would actually improve what your household drinks.
Certified, independent results come from a state/province-licensed lab, not a company with a sales incentive — ask for a lab that reports to the EPA or your state.
Frequently asked questions
Is Joliet tap water safe to drink?
Yes. Joliet's municipal water meets all EPA legal limits — every detected contaminant is below the limit. Lead is the main thing to watch, and it usually comes from a home's own plumbing, not the treated supply.
Who tests Joliet's water, and how often?
City of Joliet Department of Public Utilities is required by the EPA to test and publish an annual Consumer Confidence Report (CCR), linked on this page.
Where does Joliet drinking water come from?
Groundwater (deep sandstone wells)
Should I filter Joliet's tap water?
For most people, no — the water already meets all legal limits. A filter is worth considering only if you're on older plumbing (lead/copper), have a compromised immune system, or dislike the taste/chlorine.
Is Joliet water hard?
Joliet water is very hard at 17.53 GPG (300 ppm). Hardness is separate from safety — it affects scale and appliances, not health. See the Joliet water hardness page for the full picture.
Sources & method
All contaminant levels are drawn from official, published data — EWG tap water database (Aug 2026) (source). We cite the legal limit for each contaminant so you never see a bare scare number.
- · City of Joliet Department of Public Utilities — water-quality report we reviewed
- · USGS — Water Hardness
- · EPA — Drinking Water Regulations
- · CDC — Drinking Water
- · EWG — Tap Water Database
- · Our complete contaminants guide (what's detected vs. what matters, how limits are set)
- · How to read your water quality report — line by line
Compare Joliet to Other Illinois Cities
How Joliet's water quality stacks up against nearby cities — same Illinois data, same legal limits.
Other Safe-to-Drink Water Cities
Joliet is one of many cities whose water meets every health limit. Here are a few more to compare.
Explore More
💧 Don’t rely on old numbers
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💧 Water treatment pros: this page is yours to share
This page helps customers understand what's in their water and whether they need a filter — so they can weigh whether service is worth it. We recommend sharing this page along with our complete contaminants guide in your next quote or follow-up to fully explain the value of your services.