Is Warsaw, CA Tap Water Safe to Drink?
Graded A-, with 5 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
87.8/100
waterverge.com Warsaw, CA — Water Quality Report
Warsaw's drinking water received a grade of A- (87.8 out of 100), indicating good water quality. The city's 1 water system serves approximately 598 residents using groundwater.
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 19 violations on record, including 2 health-based violations. 5 remain unresolved.
What to know about Warsaw's water
Warsaw ranks #201 out of 694 cities in California for water quality, placing it mid-range in the state.
Warsaw 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, Warsaw may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Warsaw, CA water safe to drink?
Warsaw's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (87.8/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 598 residents using groundwater (wells).
Recent water quality updates for Warsaw
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Warsaw's water quality assessment. Grade: A- (87.8/100).
Contaminants: Consumer Confidence Rule.
Contaminants: Revised Total Coliform Rule.
Federal disaster declaration (FEMA DR-3592). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-4683). Flood event — may have impacted local water infrastructure.
Contaminants: Nitrate.
Key contaminant findings
Based on the most recent EPA sampling data for Warsaw's water supply.
Well within EPA limits.
Violation history
Warsaw's water system has 19 total violations on record, including 2 health-based violations. 5 remain unresolved. 2 violations were issued in the last 5 years.
Flood & environmental risk
Los Angeles County has experienced 10 federally declared disasters since 1980. 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 San Gabriel R Bl Santa Fe Dam Nr Baldwin Pk, San Gabriel R Ab Whittier Narrows Dam, Rio Hondo Ab Whittier Narrows Dam, Rio Hondo Bl Whittier Narrows Dam.
Where does Warsaw's water come from?
Warsaw's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 598 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include San Gabriel R Bl Santa Fe Dam Nr Baldwin Pk (river), San Gabriel R Ab Whittier Narrows Dam (river), Rio Hondo Ab Whittier Narrows Dam (river), Rio Hondo Bl Whittier Narrows Dam (river).
What Warsaw residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Warsaw'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.
Warsaw'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
Flood & disaster history
Los Angeles County has experienced 10 federally declared disasters since 1980. 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 Warsaw compares by contaminant
Explore where Warsaw ranks among all California cities for specific contaminants.
Water source & infrastructure
Where Warsaw's water comes from
Warsaw'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 598 people through 1 water system.
Water bodies near Warsaw
Warsaw is located near 4 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Warsaw
| System Name | PWSID | Population | Source |
|---|---|---|---|
| MECKS WHISPERING PINES II LLC | IN5243033 | 598 | GW |
How Warsaw compares
Full California rankings →Warsaw's score of 87.8/100 is above the average of 57/100 among major California cities. It outscores 8 of 10 nearby cities.
Nearby cities
View California rankings →About Warsaw, CA
Wikipedia →West Covina is a city in Los Angeles County, California, United States. Located 19 miles (31 km) east of downtown Los Angeles in the eastern San Gabriel Valley, it is part of Greater Los Angeles. The population for the city was 109,501 at the 2020 census.
Learn more about your water
Guides and resources related to Warsaw's water quality findings.
Explore water quality across Kosciusko
Frequently asked questions
Is Warsaw, CA tap water safe to drink?
Warsaw's water quality earned a grade of A- (87.8/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #201 out of 694 cities tested in California.
What contaminants are in Warsaw's water?
Lead was measured at 0.0 ppb (90th percentile). 19 violations are on record.
How is Warsaw'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 Warsaw?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Warsaw's water come from?
Warsaw's water is sourced from Groundwater. The city has 1 water system serving approximately 598 residents.
What health violations has Warsaw's water system had?
Warsaw 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. 5 violations remain unresolved.
Is Warsaw's groundwater at risk of contamination?
Warsaw 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 19 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 Warsaw's water compare to other cities?
Warsaw ranks #201 out of 694 cities in California (better than 71% of state cities) and #3849 out of 15744 cities nationally (76th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Warsaw's small water system affect quality?
Warsaw's system serves approximately 598 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 19 violations on record.