Water Quality in Mount Prospect, IL: 4 Violations — Grade C
Grade C · Score 68/100 · 1 water system · Updated 2026-05-03
Mount Prospect's water has moderate compliance issues. Residents in affected areas should consider filtration.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Mount Prospect in IL has 4 EPA water violations documented — the compliance history below covers what was flagged and which local systems are associated with each finding.
Water Quality by ZIP Code in Mount Prospect
Water quality varies across Mount Prospect's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 60056 | C | 68 | 4 | 0 | View report → |
Water Quality Overview
Mount Prospect, Illinois receives a water quality grade of C with an overall score of 68 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 1 water system serving Mount Prospect have accumulated 4 EPA violations (all monitoring/reporting type). These violations are tracked across 1 ZIP codes serving approximately 41,000 people.
What Grade C Means
A grade of C indicates moderate compliance issues. Mount Prospect's water systems have some violations that warrant attention. While the water may still be safe for most people, residents in affected ZIP codes should consider additional testing or filtration.
Lead Levels
The average 90th percentile lead level across Mount Prospect water systems is 0.0043 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 84% of homes built before 1986, Mount Prospect has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Radon Risk
Mount Prospect is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Mount Prospect
Mount Prospect is served by 1 community water system regulated under the Safe Drinking Water Act. These systems collectively serve approximately 41,000 people across 1 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 10 enforcement actions against water systems serving Mount Prospect. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Mount Prospect
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
Request your CCR — your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test — certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration — NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories — monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in Mount Prospect Water Systems
The following contaminants have been detected or caused violations across Mount Prospect's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Surface Water Treatment Rule | Treatment Technique | N/A | 2 | 1 | No |
| Bromate | Disinfection Byproducts | 0.01 mg/L | 1 | 1 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
EPA Enforcement History
The EPA and state regulators have taken 10 enforcement actions against water systems serving Mount Prospect. Recent actions:
| Date | Action Type |
|---|---|
| 2025-08-25 | State Informal Action |
| 2025-06-20 | State Informal Action |
| 2025-01-24 | State Informal Action |
| 2025-01-24 | State Informal Enforcement |
| 2025-01-21 | State Order Extension |
| 2025-01-13 | State Order Extension |
| 2024-10-11 | State Informal Action |
| 2024-10-11 | State Informal Enforcement |
| 2021-01-13 | State Order Extension |
| 2021-01-06 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-08-25.
Mount Prospect vs. Nearby Illinois Cities
How Mount Prospect's water quality compares to similar cities in Illinois:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Mount Prospect | C | 4 | 1 | 41,000 |
| Alden | D | 0 | 1 | 40,661 |
| Crystal Lake | C | 6 | 1 | 40,661 |
| Bartlett | C | 0 | 1 | 41,500 |
Common Questions About Mount Prospect Water
These are the most common questions residents search for about water quality in Mount Prospect, Illinois:
Is Mount Prospect water hard or soft? Water hardness varies by source. Mount Prospect's 1 water system uses a single source. Check your ZIP code report for specific hardness data.
Can I drink Mount Prospect tap water? Mount Prospect's water receives a grade of C (68/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Mount Prospect? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Mount Prospect vs. Illinois Average
Understanding how Mount Prospect compares to the broader Illinois average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below — water quality can vary significantly even within Mount Prospect.
ZIP Codes in Mount Prospect
Mount Prospect spans 1 ZIP code. The ZIP with the lowest water quality score is 60056. Each ZIP code has its own water quality profile based on the specific water system serving that area. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Updated daily.