Is Santa Rosa Rancheria, CA Tap Water Safe to Drink?
Graded D, with 17 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
48/100
waterverge.com Santa Rosa Rancheria, CA — Water Quality Report
Santa Rosa Rancheria's drinking water received a grade of D (48 out of 100), indicating poor water quality. The city's 1 water system serves approximately 1,000 residents using purchased ground water.
Lead levels were measured at 3.4 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 117 violations on record, including 25 health-based violations. 17 remain unresolved.
What to know about Santa Rosa Rancheria's water
Santa Rosa Rancheria ranks #623 out of 694 cities in California for water quality, placing it among the lowest-rated in the state.
Santa Rosa Rancheria purchases its water from a regional wholesaler, meaning quality depends on both the supplier's treatment and the local distribution system's condition.
As a small community water system, Santa Rosa Rancheria may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 33 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Santa Rosa Rancheria, CA water safe to drink?
Santa Rosa Rancheria's drinking water has significant quality concerns based on EPA testing data. With a grade of D (48/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 1,000 residents using groundwater (wells).
Recent water quality updates for Santa Rosa Rancheria
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Santa Rosa Rancheria's water quality assessment. Grade: D (48/100).
Contaminants: Chlorine.
Contaminants: Public Notice, Chlorine, Revised Total Coliform Rule.
Contaminants: Revised Total Coliform Rule, Public Notice.
Federal disaster declaration (FEMA DR-3592). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3591). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Santa Rosa Rancheria's water supply.
Well within EPA limits.
Violation history
Santa Rosa Rancheria's water system has 117 total violations on record, including 25 health-based violations. 17 remain unresolved. 33 violations were issued in the last 5 years.
Flood & environmental risk
Kings County has experienced 9 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 Nf Kings R A 24Th Ave Br Nr Lemoore.
Where does Santa Rosa Rancheria's water come from?
Santa Rosa Rancheria's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,000 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Nf Kings R A 24Th Ave Br Nr Lemoore (river).
What Santa Rosa Rancheria residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Santa Rosa Rancheria'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.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Santa Rosa Rancheria'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
Kings County has experienced 9 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. | 3.4 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Santa Rosa Rancheria compares by contaminant
Explore where Santa Rosa Rancheria ranks among all California cities for specific contaminants.
Water source & infrastructure
Where Santa Rosa Rancheria's water comes from
Santa Rosa Rancheria purchases its water supply from a regional wholesale provider rather than treating raw water directly.
Water quality depends on both the wholesaler's treatment standards and the condition of Santa Rosa Rancheria's local distribution pipes and storage facilities.
Purchased water systems are common in suburban areas and smaller communities that lack the infrastructure for independent treatment.
The system is operated by native american ownership and serves approximately 1,000 people through 1 water system.
Water bodies near Santa Rosa Rancheria
Santa Rosa Rancheria is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Santa Rosa Rancheria
| System Name | PWSID | Population | Source |
|---|---|---|---|
| Santa Rosa Rancheria | 090600148 | 1,000 | GWP |
How Santa Rosa Rancheria compares
Full California rankings →Santa Rosa Rancheria's score of 48/100 is below the average of 57/100 among major California cities. It outscores 5 of 10 nearby cities.
Nearby cities
View California rankings →About Santa Rosa Rancheria, CA
Wikipedia →Lemoore is a city in Kings County, California, United States. Lemoore is located 7.5 miles (12 km) west-southwest of Hanford, at an elevation of 230 feet (70 m). It is part of the Hanford-Corcoran Metropolitan Statistical Area. The population was 27,038 at the 2020 Census.
Learn more about your water
Guides and resources related to Santa Rosa Rancheria's water quality findings.
Frequently asked questions
Is Santa Rosa Rancheria, CA tap water safe to drink?
Santa Rosa Rancheria's water quality earned a grade of D (48/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #623 out of 694 cities tested in California.
What contaminants are in Santa Rosa Rancheria's water?
Lead was measured at 3.4 ppb (90th percentile). 117 violations are on record.
How is Santa Rosa Rancheria'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 Santa Rosa Rancheria?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Santa Rosa Rancheria's water come from?
Santa Rosa Rancheria's water is sourced from Purchased ground water. The city has 1 water system serving approximately 1,000 residents.
What health violations has Santa Rosa Rancheria's water system had?
Santa Rosa Rancheria has 25 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. 17 violations remain unresolved.
Is Santa Rosa Rancheria's groundwater at risk of contamination?
Santa Rosa Rancheria 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 117 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 Santa Rosa Rancheria's water compare to other cities?
Santa Rosa Rancheria ranks #623 out of 694 cities in California (better than 10% of state cities) and #13540 out of 15744 cities nationally (14th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Santa Rosa Rancheria's small water system affect quality?
Santa Rosa Rancheria's system serves approximately 1,000 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 117 violations on record.