01The verdict: is Oostburg water safe?
Oostburg's tap water meets most EPA standards but has areas that warrant attention. With a grade of B+ (84.4/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 3,110 residents using groundwater (wells).
2 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 ↓Top half in Wisconsin
Oostburg ranks #180 of 441 graded Wisconsin cities.
See the comparison ↓Lead is approaching its limit
Measured at 10.5 ppb — 70% of the 15 ppb limit. Within the rules, but with less headroom than you'd want.
See the ledger ↓Oostburg's drinking water received a grade of B+ (84.4 out of 100), indicating good water quality. The city's 1 water system serves approximately 3,110 residents using groundwater.
Lead levels were measured at 10.5 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program. The system has 6 violations on record, including 0 health-based violations. 2 remain unresolved.
Oostburg ranks #180 out of 441 cities in Wisconsin for water quality, placing it mid-range in the state. Oostburg 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. While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection. As a small community water system, Oostburg may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
02What's in Oostburg's water
Every contaminant flagged in Oostburg, 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.
Near Limit — EPA Action Level: 15 ppb
Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb — no lead level is considered safe for children. An NSF 53-certified filter provides additional protection, and running the cold tap 30 seconds after stagnation reduces exposure.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. | 10.5 | 15 | ppb | Inorganic | Near Limit |
Cities ranked by 90th-percentile lead PF PFAS in Wisconsin
Cities ranked by compounds detected Cu Copper in Wisconsin
Cities ranked by 90th-percentile copper
03Oostburg'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 6 violations on record, including 0 health-based violations. 2 remain unresolved.
All ten of the last ten years were clean — no EPA violations recorded for Oostburg.
▲ Up 5.5 ppb since 1993. Latest reading: 11 ppb (2023) — 70% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Oostburg's water comes from
Oostburg's drinking water is drawn from underground aquifers through wells.
Groundwater
Underground aquifers reached by wells — naturally filtered, but can carry minerals like arsenic and nitrate.
Local treatment
Groundwater generally needs less treatment — typically disinfection and, where needed, mineral removal.
1 system
1 water system, operated under local government ownership.
3,110 people
Residents served across Oostburg's service area.
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 local government ownership and serves approximately 3,110 people through 1 water system.
| System name | PWSID | Population | Source |
|---|---|---|---|
| OOSTBURG WATERWORKS | WI4600445 | 3,110 | Groundwater |
Water bodies near Oostburg
These water bodies shape the regional watershed and can indirectly affect groundwater quality.
05Pressure on Oostburg'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
5 facilities within 10 miles reported 2k 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
4 federal disaster declarations on record for Sheboygan County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.
Superfund proximity
2 National Priorities List sites within 10 miles. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
06How Oostburg compares
Scores for nearby Wisconsin cities on one line, with the average marked.
dashed line = Wisconsin average (65/100)
Oostburg scores 84.4/100 — above the Wisconsin average of 65/100. It outscores 7 of 10 nearby cities. Full Wisconsin rankings →
90.2 / 100FMadison, WI
35.4 / 100DGreen Bay, WI
54 / 100CRacine, WI
69.5 / 100DKenosha, WI
45.8 / 100DWaukesha, WI
47.1 / 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 Oostburg's water — not generic advice.
Filter drinking & cooking water
Basic carbon filter for extra protection. Lead detected at 10.5 ppb
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 Oostburg 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 Oostburg, WI tap water safe to drink?
Oostburg's water quality earned a grade of B+ (84.4/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #180 out of 441 cities tested in Wisconsin.
What contaminants are in Oostburg's water?
Lead was measured at 10.5 ppb (90th percentile). 6 violations are on record.
How is Oostburg'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 Oostburg?
While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Oostburg's water come from?
Oostburg's water is sourced from Groundwater. The city has 1 water system serving approximately 3,110 residents.
Is Oostburg's groundwater at risk of contamination?
Oostburg 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 6 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 Oostburg's water compare to other cities?
Oostburg ranks #180 out of 441 cities in Wisconsin (better than 59% of state cities) and #5864 out of 15382 cities nationally (62th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Oostburg's small water system affect quality?
Oostburg's system serves approximately 3,110 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 6 violations on record.