01The verdict: is Oakwood water safe?
Oakwood's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (86.3/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 1,467 residents using groundwater (wells).
9 unresolved violations on record
EPA records show open compliance items for this system. Most are administrative, but unresolved items are worth watching.
See what was cited ↓Lead is well under the limit
90th-percentile lead is 4.3 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.
See the trend ↓1 violation in the last five years
Recent compliance history is the best predictor of future problems — the year-by-year record is below.
See the record ↓Oakwood's drinking water received a grade of A- (86.3 out of 100), indicating good water quality. The city's 3 water systems serve approximately 1,467 residents using groundwater.
Lead levels were measured at 4.3 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 49 violations on record, including 18 health-based violations. 9 remain unresolved.
Oakwood ranks #330 out of 882 cities in Illinois for water quality, placing it mid-range 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, Oakwood may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
02What's in Oakwood's water
Every contaminant flagged in Oakwood, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.
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. | 4.3 | 15 | ppb | Inorganic | Safe |
Cities ranked by 90th-percentile lead PF PFAS in Illinois
Cities ranked by compounds detected Cu Copper in Illinois
Cities ranked by 90th-percentile copper
03Oakwood's ten-year track record
Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 49 violations on record, including 18 health-based violations. 9 remain unresolved.
7 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.
▲ Up 2.4 ppb since 1993. Latest reading: 2.4 ppb (2025) — 16% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Oakwood's water comes from
Oakwood's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface Water
Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.
Local treatment
Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.
3 systems
3 water systems, operated under private ownership.
1,467 people
Residents served across Oakwood's service area.
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 private ownership and serves approximately 1,467 people through 3 water systems.
| System name | PWSID | Population | Source |
|---|---|---|---|
| PRAIRIE PATH WATER COMPANY-OAKWOOD | IL1830600 | 1,600 | Surface Water |
| PRAIRIE PATH WATER COMPANY-LAKE WILDWOOD | IL1235200 | 1,295 | Groundwater |
| PRAIRIE PATH WATER COMPANY-CEDAR WATER | IL0955150 | 172 | Groundwater |
Water bodies near Oakwood
These water bodies shape the regional watershed and can indirectly affect groundwater quality.
05Pressure on Oakwood's watershed
Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.
Industrial discharge
4 facilities within 10 miles reported 1k lb released to surface water in the latest EPA Toxics Release Inventory. Proximity doesn't equal tap contamination — treatment and hydrology decide — but it's pressure on the watershed.
Flood & storm history
6 federal disaster declarations on record for McHenry County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.
Superfund proximity
1 National Priorities List site within 10 miles. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
06How Oakwood compares
Scores for nearby Illinois cities on one line, with the average marked.
dashed line = Illinois average (55/100)
Oakwood scores 86.3/100 — above the Illinois average of 55/100. It outscores 10 of 10 nearby cities. Full Illinois rankings →
35.2 / 100DAurora, IL
45.5 / 100FJoliet, IL
38.5 / 100BNaperville, IL
81.2 / 100FRockford, IL
38.4 / 100FKankakee, IL
42.6 / 100
Compare all cities in the county — grades, violations, and contaminant data side by side.→
07What to do at home
Steps matched to what testing actually found in Oakwood's water — not generic advice.
A basic carbon filter still helps
Oakwood's water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.
Compare tested filters →Flush taps & check your service line
Lead leaches from pipes as water sits. Run cold water 30 seconds before drinking (especially mornings), and ask the utility whether your address still has a lead service line.
Lead risks explained →Watch for Oakwood alerts
This area has a history of flood declarations — after severe weather, watch for boil-water advisories from the utility, and check the live alerts on this page.
All water alerts →Frequently asked questions
Is Oakwood, IL tap water safe to drink?
Oakwood's water quality earned a grade of A- (86.3/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #330 out of 882 cities tested in Illinois.
What contaminants are in Oakwood's water?
Lead was measured at 4.3 ppb (90th percentile). 49 violations are on record.
How is Oakwood'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 Oakwood?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Oakwood's water come from?
Oakwood's water is sourced from Groundwater. The city has 3 water systems serving approximately 1,467 residents.
What health violations has Oakwood's water system had?
Oakwood has 18 health-based violations on record. The most recent violation was recorded in December 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 9 violations remain unresolved.
Is Oakwood's groundwater at risk of contamination?
Oakwood 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 49 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 Oakwood's water compare to other cities?
Oakwood ranks #330 out of 882 cities in Illinois (better than 63% of state cities) and #4748 out of 15382 cities nationally (69th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.