Is Isleton, CA Tap Water Safe to Drink?
Graded C+, with 13 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
68.5/100
waterverge.com Isleton, CA — Water Quality Report
Isleton's drinking water received a grade of C+ (68.5 out of 100), indicating fair water quality. The city's 5 water systems serve approximately 625 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 125 violations on record, including 52 health-based violations. 13 remain unresolved.
What to know about Isleton's water
Isleton ranks #524 out of 694 cities in California for water quality, placing it among the lowest-rated in the state.
Isleton 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, Isleton may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 6 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Isleton, CA water safe to drink?
Isleton's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (68.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 5 water systems serve approximately 625 residents using groundwater (wells).
Recent water quality updates for Isleton
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Isleton's water quality assessment. Grade: C+ (68.5/100).
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.
1 health-based. Contaminants: Revised Total Coliform 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.
Key contaminant findings
Based on the most recent EPA sampling data for Isleton's water supply.
Well within EPA limits.
Violation history
Isleton's water system has 125 total violations on record, including 52 health-based violations. 13 remain unresolved. 6 violations were issued in the last 5 years.
Flood & environmental risk
Sacramento County has experienced 10 federally declared disasters since 1972. 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 Holland Cut Nr Bethel Island, Dutch Slough Bl Jersey Island Rd A Jersey Island, Old R A Quimby Island Nr Bethel Island, False R Nr Oakley, Old R A Franks Tract Nr Terminous.
Where does Isleton's water come from?
Isleton's drinking water comes from groundwater (wells), supplied by 5 water systems serving approximately 625 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Holland Cut Nr Bethel Island (river), Dutch Slough Bl Jersey Island Rd A Jersey Island (river), Old R A Quimby Island Nr Bethel Island (river), False R Nr Oakley (river), Old R A Franks Tract Nr Terminous (river).
What Isleton residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Isleton'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.
Isleton'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
Sacramento County has experienced 10 federally declared disasters since 1972. 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 Isleton compares by contaminant
Explore where Isleton ranks among all California cities for specific contaminants.
Water source & infrastructure
Where Isleton's water comes from
Isleton'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 625 people through 5 water systems.
Water bodies near Isleton
Isleton is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Isleton
| System Name | PWSID | Population | Source |
|---|---|---|---|
| RIVER'S EDGE MARINA & RESORT | CA3400107 | 210 | GW |
| VIEIRA'S RESORT, INC | CA3400164 | 200 | GW |
| B & W RESORT MARINA | CA3400103 | 100 | GW |
| HAPPY HARBOR (SWS) | CA3400128 | 60 | GW |
| KORTHS PIRATES LAIR | CA3400135 | 55 | GW |
How Isleton compares
Full California rankings →Isleton's score of 68.5/100 is above the average of 57/100 among major California cities. It outscores 6 of 10 nearby cities.
Nearby cities
View California rankings →About Isleton, CA
Learn more about your water
Guides and resources related to Isleton's water quality findings.
Explore water quality across Sacramento
Frequently asked questions
Is Isleton, CA tap water safe to drink?
Isleton's water quality earned a grade of C+ (68.5/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #524 out of 694 cities tested in California.
What contaminants are in Isleton's water?
Lead was measured at 0.0 ppb (90th percentile). 125 violations are on record.
How is Isleton'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 Isleton?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Isleton's water come from?
Isleton's water is sourced from Groundwater. The city has 5 water systems serving approximately 625 residents.
What health violations has Isleton's water system had?
Isleton has 52 health-based violations on record. The most recent violation was recorded in October 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 13 violations remain unresolved.
Is Isleton's groundwater at risk of contamination?
Isleton 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 125 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 Isleton's water compare to other cities?
Isleton ranks #524 out of 694 cities in California (better than 24% of state cities) and #11072 out of 15744 cities nationally (30th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.