Is Joliet, IL tap water safe?
Supplied by Joliet Water System · serves 160,000 people (49,000 connections) · Groundwater · EPA ID IL1970450
Data: U.S. EPA · How we read the data · How we check it
Most of Joliet gets its water from Joliet Water System. Parts of the city are served by 11 smaller systems: Southeast Joliet Sanitary District (2,000 people), Crystal Lawns Addition Improvement Association (1,435 people), Stateville Correctional Center Water System (992 people), Lakewood Shores Improvement Association (868 people) and 7 more. Your water bill names your system.
Summary
No federal limits exceeded in EPA data.
- PFAS
- Not detectedNone of 29 PFAS found above EPA's reporting limits in 22 samples (2023–2025).
- Lithium
- Above screening levelHighest result 54.7 ppb. EPA uses 10 ppb to decide what to study further. It is not a health limit, and there is no federal limit for lithium. About 1 in 4 systems tested were above it.
- Lead
- Below action level6.53 ppb (parts per billion) at the 90th percentile: 9 in 10 homes sampled were at or below it. Action level 15 ppb, falling to 10 ppb in Nov 2027. Monitoring period ending Jun 2026. Your home's pipes can make yours higher.
- Violations
- Resolved1 health-based violation since 2016, most recently Oct 2024.
- Built before 1986, or not sure what your service line is made of? Check your service line and test your tap. Utility data can't show your pipes.
- Tested your own tap? Compare your result with these numbers. Moving? Compare this system with another.
- Read Joliet Water System's annual water quality report (Consumer Confidence Report). It lists every regulated contaminant tested and is usually on the utility's website or mailed with your bill, and you can also request it at (815) 724-4222. EPA: how to find it.
PFAS (“forever chemicals”)
EPA UCMR 5: 11 entry points tested Feb 2025 to Aug 2025. "Average" is the highest entry-point average (non-detects counted as zero), the way EPA compares UCMR 5 results to the limits. ppt = parts per trillion. These results do not determine compliance.
| Contaminant | Highest average |
|---|---|
| PFOA Not detected Limit 4 ppt | – |
| PFOS Not detected Limit 4 ppt | – |
| PFHxS Not detected Limit 10 ppt | – |
| PFNA Not detected Limit 10 ppt | – |
| HFPO-DA (GenX) Not detected Limit 10 ppt | – |
| Hazard Index (a combined score for PFHxS, PFNA, GenX and PFBS, where above 1 is over the limit) Not detected Limit 1 | – |
| PFBS Not detected Guideline 2,000 ppt | – |
| PFBA Not detected Guideline 6,000 ppt | – |
| PFHxA Not detected Guideline 3,000 ppt | – |
29 PFAS tested, 0 detected at least once. "Not detected" means below EPA's reporting limit (about 2 to 20 ppt depending on the chemical), not proven zero. PFAS not listed were not detected. The limits for PFHxS, PFNA, GenX and the Hazard Index were proposed for rescission in May 2026. That proposal is not final. Systems have until 2029 to meet the limits.
Lithium
Detected in 22 of 22 samples. Highest result 54.7 ppb. EPA's non-enforceable screening level is 10 ppb. Above screening level The screening level is how EPA decides what to study further, not a health limit. There is no federal limit for lithium and no filter is certified to remove it. About lithium.
Lead and copper
Latest 90th percentile: 6.53 ppb lead (Jan 2026 – Jun 2026). Below action level
Highest since 2016: 9.03 ppb (Dec 2025).
| Monitoring period | Lead (90th pct.) |
|---|---|
| Jan 2026 – Jun 2026 | 6.53 ppb |
| Jul 2025 – Dec 2025 | 9.03 ppb |
| Jan 2025 – Dec 2025 | 0 ppb |
Earlier results (9)
| Jan 2025 – Jun 2025 | 8.7 ppb |
| Jul 2024 – Dec 2024 | 7.77 ppb |
| Jan 2024 – Jun 2024 | 4.73 ppb |
| Jul 2023 – Dec 2023 | 5.52 ppb |
| Jan 2023 – Jun 2023 | 4.2 ppb |
| Jul 2022 – Dec 2022 | 4.39 ppb |
| Jan 2019 – Dec 2021 | 7.23 ppb |
| Jan 2018 – Dec 2018 | 8.18 ppb |
| Jan 2015 – Dec 2017 | 7.69 ppb |
Lead comes from pipes and fixtures, not the source water, so it varies home to home. The 90th percentile means 9 in 10 sampled homes were at or below it. More on lead.
Violations
| When | What happened |
|---|---|
| Oct 2024 | The system did not publish the required inventory of lead service lines (due October 2024). It says nothing about lead levels in the water. EPA record: Lead and copper rule revisions · LSL Inventory Resolved |
Health-based violations mean a contaminant exceeded a limit or a required treatment step was missed. Monitoring and reporting violations mean required tests or reports were late or missing, so the water's quality during that time is unknown. The total includes every violation in EPA's records, most of them paperwork.
Earlier EPA testing (2013–2020)
| Contaminant | Highest | Guideline |
|---|---|---|
| Manganese | 99.5 ppb | 300 ppb |
| Strontium | 3.1 ppm | 1.5 ppm |
| Molybdenum | 2.6 ppb | 40 ppb |
| 1,4-Dioxane | 0.15 ppb | 0.35 ppb |
| Chlorate | 500 ppb | 210 ppb |
Where it serves
Joliet
ZIP codes the system reported serving: 60403, 60404, 60410, 60431, 60432, 60433, 60435, 60436, 60441, 60447, 60451, 60586
Nearby utilities
- Crest Hill Water System Crest Hill · 4 mi · PFAS above limit
- Romeoville Water System Romeoville · 8 mi
- Channahon Water System Channahon · 9 mi · PFAS above limit
- Plainfield Water System Plainfield · 9 mi
- Illinois American Water – West Suburban Bolingbrook · 12 mi
- Naperville Water System Naperville · 16 mi
Questions
Is Joliet tap water safe to drink?
Most of Joliet gets its water from Joliet Water System. Joliet Water System had 1 health-based violation since 2016, all since resolved. EPA testing found no PFAS above the federal limits. Federal data can't tell you about your own pipes: lead comes from service lines and plumbing, so test your tap if your home was built before 1986. For the official word, read the utility's annual Consumer Confidence Report.
Does Joliet water have PFAS?
EPA tested Joliet Water System for 29 PFAS between Feb 2025 and Aug 2025 and none were detected above the reporting limits (about 2 to 20 ppt depending on the chemical).
What is the lead level in Joliet water?
The most recent 90th-percentile lead result for Joliet Water System is 6.53 ppb, for the period ending Jun 2026. The federal action level is 15 ppb, falling to 10 ppb in November 2027. The 90th percentile means 9 in 10 homes sampled were at or below this number. Individual homes can be higher.
Check these numbers yourself
Every figure on this page comes from public EPA records. You don't have to take our word for it:
- EPA's own report for IL1970450: violations, enforcement and inspections, straight from EPA.
- EPA UCMR 5 data: the PFAS and lithium results (search the file for PWSID IL1970450).
- EPA SDWIS download: the lead results, population and violation records we use.
- The utility's annual water quality report (Consumer Confidence Report): ask Joliet Water System at (815) 724-4222, or see EPA's guide to finding it.
Found something that doesn't match? Tell us and we'll check it against EPA's records. How we check our data.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.