Is Cairo, IL Tap Water Safe to Drink?
Graded A, with 1 unresolved violation on record. See what was cited — and what it means for your tap. What to do next ↓
91.6/100
waterverge.com Cairo, IL — Water Quality Report
Cairo's drinking water received a grade of A (91.6 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 1,821 residents using groundwater.
Lead levels were measured at 1.0 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 3 violations on record, including 0 health-based violations. 1 remains unresolved.
What to know about Cairo's water
Cairo ranks #96 out of 891 cities in Illinois for water quality, placing it above average in the state.
Cairo relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, Cairo may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Cairo, IL water safe to drink?
Cairo's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (91.6/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 1,821 residents using groundwater (wells).
Recent water quality updates for Cairo
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Cairo's water quality assessment. Grade: A (91.6/100).
Federal disaster declaration (FEMA DR-4461). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3230). Hurricane event — may have impacted local water infrastructure.
Contaminants: Surface Water Treatment Rule.
Contaminants: Gross Alpha, Excl. Radon and U.
Key contaminant findings
Based on the most recent EPA sampling data for Cairo's water supply.
Well within EPA limits.
Violation history
Cairo's water system has 3 total violations on record, including 0 health-based violations. 1 remain unresolved.
Flood & environmental risk
Madison County has experienced 6 federally declared disasters since 1969. 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 Mississippi River Pool Lock And Dam 26 At Alton,Il, Mill Creek Near Florissant, Coldwater Creek Near Black Jack.
Where does Cairo's water come from?
Cairo's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,821 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Mississippi River Pool Lock And Dam 26 At Alton,Il (river), Mill Creek Near Florissant (river), Coldwater Creek Near Black Jack (river).
What Cairo residents can do
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.
Cairo's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.
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 Cairo
Industrial polluters nearby
Reported releases to surface water by facilities near Cairo, ranked by pounds discharged annually.
Total reported releases to surface water: 142,825 lbs
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
PHOENIX PAPER WICKLIFFE LLC WICKLIFFE, KY42087 | Methanol | 142,825 | 6.5 mi |
BUNGE CHEVRON AG RENEWABLES LLC CAIRO, IL62914 | — | — | 0.7 mi |
INGEVITY VIRGINIA CORP-WICKLIFFE CARBON PLANT WICKLIFFE, KY42087 | — | — | 7.4 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Drought conditions
D2 — severe droughtAlexander County is currently in D2 (severe 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
Madison County has experienced 6 federally declared disasters since 1969. 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. | 1.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Cairo compares by contaminant
Explore where Cairo ranks among all Illinois cities for specific contaminants.
Water source & infrastructure
Where Cairo's water comes from
Cairo's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by private ownership and serves approximately 1,821 people through 1 water system.
Water bodies near Cairo
Cairo is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Cairo
| System Name | PWSID | Population | Source |
|---|---|---|---|
| IL AMERICAN-CAIRO | IL0035030 | 1,821 | GW |
How Cairo compares
Full Illinois rankings →Cairo's score of 91.6/100 is above the average of 56/100 among major Illinois cities. It outscores 9 of 10 nearby cities.
Nearby cities
View Illinois rankings →About Cairo, IL
Wikipedia →Godfrey is a village in Madison County, Illinois, United States. The population was 17,825 at the 2020 census. Godfrey is located within the River Bend portion of the Greater St. Louis metropolitan area.
Learn more about your water
Guides and resources related to Cairo's water quality findings.
Explore water quality across Alexander
Frequently asked questions
Is Cairo, IL tap water safe to drink?
Cairo's water quality earned a grade of A (91.6/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #96 out of 891 cities tested in Illinois.
What contaminants are in Cairo's water?
Lead was measured at 1.0 ppb (90th percentile). 3 violations are on record.
How is Cairo'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 Cairo?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Cairo's water come from?
Cairo's water is sourced from Groundwater. The city has 1 water system serving approximately 1,821 residents.
Is Cairo's groundwater at risk of contamination?
Cairo uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 3 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does Cairo's water compare to other cities?
Cairo ranks #96 out of 891 cities in Illinois (better than 89% of state cities) and #1593 out of 15744 cities nationally (90th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Cairo's small water system affect quality?
Cairo's system serves approximately 1,821 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 3 violations on record.