Is Colp, IL Tap Water Safe to Drink?
Graded B-, with 10 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
73.7/100
waterverge.com Colp, IL — Water Quality Report
Colp's drinking water received a grade of B- (73.7 out of 100), indicating fair water quality. The city's 1 water system serves approximately 506 residents using purchased surface water.
Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 14 violations on record, including 2 health-based violations. 10 remain unresolved.
What to know about Colp's water
Colp ranks #696 out of 891 cities in Illinois for water quality, placing it among the lowest-rated in the state.
The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.
As a small community water system, Colp may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 6 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Colp, IL water safe to drink?
Colp's drinking water has significant quality concerns based on EPA testing data. With a grade of B- (73.7/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 506 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Colp
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Colp's water quality assessment. Grade: B- (73.7/100).
Contaminants: LEAD AND COPPER RULE REVISIONS.
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.
Contaminants: Public Notice, Consumer Confidence Rule.
Federal disaster declaration (FEMA DR-3230). Hurricane event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Colp's water supply.
Well within EPA limits.
Violation history
Colp's water system has 14 total violations on record, including 2 health-based violations. 10 remain unresolved. 6 violations were issued in the last 5 years.
Flood & environmental risk
Williamson County has experienced 1 federally declared disaster since 2005. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Big Muddy River.
Where does Colp's water come from?
Colp's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 506 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Big Muddy River (river).
What Colp residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Colp's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Colp
Industrial polluters nearby
Reported releases to surface water by facilities near Colp, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
CROWNLINE BOATS WEST FRANKFORT, IL62896 | — | — | 9.1 mi |
INTERTAPE POLYMER CORP CARBONDALE, IL62901 | — | — | 8.2 mi |
DIAGRAPH MARKING & CODING MARION, IL62959 | — | — | 5.7 mi |
GENERAL DYNAMICS ORDNANCE & TACTICAL SYSTEMS INC I AREA MARION, IL62959 | — | — | 5.4 mi |
AISIN MANUFACTURING ILLINOIS LLC MARION, IL62959 | — | — | 5.8 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Colp
Superfund sites nearby
Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
- SANGAMO ELECTRIC DUMP CRAB ORCHARD NATIONAL WILDLIFE REFUGE USDOI8.6 mi
Source: EPA Superfund National Priorities List
Drought conditions
D1 — moderate droughtWilliamson County is currently in D1 (moderate drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Flood & disaster history
Williamson County has experienced 1 federally declared disaster since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 0.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Colp compares by contaminant
Explore where Colp ranks among all Illinois cities for specific contaminants.
Water source & infrastructure
Where Colp's water comes from
Colp's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.
These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.
The system is operated by local government ownership and serves approximately 506 people through 1 water system.
Water bodies near Colp
Colp is located near 1 notable water body. As a surface water system, these water bodies may directly influence the city's drinking water supply.
Water systems serving Colp
| System Name | PWSID | Population | Source |
|---|---|---|---|
| COLP | IL1990200 | 506 | SWP |
How Colp compares
Full Illinois rankings →Colp's score of 73.7/100 is above the average of 56/100 among major Illinois cities. It outscores 7 of 10 nearby cities.
Nearby cities
View Illinois rankings →Learn more about your water
Guides and resources related to Colp's water quality findings.
Explore water quality across Williamson
Frequently asked questions
Is Colp, IL tap water safe to drink?
Colp's water quality earned a grade of B- (73.7/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #696 out of 891 cities tested in Illinois.
What contaminants are in Colp's water?
Lead was measured at 0.0 ppb (90th percentile). 14 violations are on record.
How is Colp's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in Colp?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Colp's water come from?
Colp's water is sourced from Purchased surface water. The city has 1 water system serving approximately 506 residents.
What health violations has Colp's water system had?
Colp has 2 health-based violations on record. The most recent violation was recorded in July 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 10 violations remain unresolved.
How does Colp's water compare to other cities?
Colp ranks #696 out of 891 cities in Illinois (better than 22% of state cities) and #10044 out of 15744 cities nationally (36th percentile). The grade of B- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Colp's small water system affect quality?
Colp's system serves approximately 506 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 14 violations on record.