Is Santa Ysabel, CA Tap Water Safe to Drink?
Graded D, with 36 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
48/100
waterverge.com Santa Ysabel, CA — Water Quality Report
Santa Ysabel's drinking water received a grade of D (48 out of 100), indicating poor water quality. The city's 5 water systems serve approximately 10,414 residents using groundwater.
Lead levels were measured at 5.0 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 616 violations on record, including 17 health-based violations. 36 remain unresolved.
What to know about Santa Ysabel's water
Santa Ysabel ranks #620 out of 694 cities in California for water quality, placing it among the lowest-rated in the state.
Santa Ysabel 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.
The system has seen 13 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Santa Ysabel, CA water safe to drink?
Santa Ysabel'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 5 water systems serve approximately 10,414 residents using groundwater (wells).
Recent water quality updates for Santa Ysabel
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Santa Ysabel's water quality assessment. Grade: D (48/100).
1 health-based. Contaminants: Groundwater Rule, Public Notice.
Federal disaster declaration (FEMA DR-4758). Flood event — may have impacted local water infrastructure.
Contaminants: Nitrate.
Federal disaster declaration (FEMA DR-4683). Flood event — may have impacted local water infrastructure.
Contaminants: Nitrate, Lead and Copper Rule.
Key contaminant findings
Based on the most recent EPA sampling data for Santa Ysabel's water supply.
Well within EPA limits.
Violation history
Santa Ysabel's water system has 616 total violations on record, including 17 health-based violations. 36 remain unresolved. 13 violations were issued in the last 5 years.
Flood & environmental risk
San Diego 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.
Where does Santa Ysabel's water come from?
Santa Ysabel's drinking water comes from groundwater (wells), supplied by 5 water systems serving approximately 10,414 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Santa Ysabel residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Santa Ysabel'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 Ysabel'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
San Diego 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. | 5.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Santa Ysabel compares by contaminant
Explore where Santa Ysabel ranks among all California cities for specific contaminants.
Water source & infrastructure
Where Santa Ysabel's water comes from
Santa Ysabel'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 10,414 people through 5 water systems.
Water systems serving Santa Ysabel
| System Name | PWSID | Population | Source |
|---|---|---|---|
| LAKE HENSHAW RESORT INC. | CA3700900 | 9,913 | GW |
| Santa Ysabel Main | 090600150 | 325 | GW |
| Mesa Grande - Black Canyon | 090605132 | 81 | GW |
| San Felipe Water System | 090600115 | 52 | GW |
| Mesa Grande (Tract 2) | 090605011 | 43 | GW |
How Santa Ysabel compares
Full California rankings →Santa Ysabel'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 →ZIP codes served by Santa Ysabel
The water systems serving Santa Ysabel cover 1 ZIP code. Select any ZIP to see which water systems serve that area.
About Santa Ysabel, CA
Wikipedia →Santa Ysabel is an unincorporated community in the Santa Ysabel Valley of eastern San Diego County, California.
Learn more about your water
Guides and resources related to Santa Ysabel's water quality findings.
Explore water quality across San Diego
Frequently asked questions
Is Santa Ysabel, CA tap water safe to drink?
Santa Ysabel's water quality earned a grade of D (48/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #620 out of 694 cities tested in California.
What contaminants are in Santa Ysabel's water?
Lead was measured at 5.0 ppb (90th percentile). 616 violations are on record.
How is Santa Ysabel'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 Ysabel?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Santa Ysabel's water come from?
Santa Ysabel's water is sourced from Groundwater. The city has 5 water systems serving approximately 10,414 residents.
What health violations has Santa Ysabel's water system had?
Santa Ysabel has 17 health-based violations on record. The most recent violation was recorded in May 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 36 violations remain unresolved.
Is Santa Ysabel's groundwater at risk of contamination?
Santa Ysabel 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 616 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 Ysabel's water compare to other cities?
Santa Ysabel ranks #620 out of 694 cities in California (better than 11% of state cities) and #13504 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.