Is Mount Hermon, CA Tap Water Safe to Drink?
Graded B+, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
83.5/100
waterverge.com Mount Hermon, CA — Water Quality Report
Mount Hermon's drinking water received a grade of B+ (83.5 out of 100), indicating good water quality. The city's 1 water system serves approximately 1,176 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 5 violations on record, including 1 health-based violation. 3 remain unresolved.
What to know about Mount Hermon's water
Mount Hermon ranks #304 out of 694 cities in California for water quality, placing it mid-range in the state.
Mount Hermon 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, Mount Hermon may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Mount Hermon, CA water safe to drink?
Mount Hermon's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (83.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 1,176 residents using groundwater (wells).
Recent water quality updates for Mount Hermon
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Mount Hermon's water quality assessment. Grade: B+ (83.5/100).
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.
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: Groundwater Rule.
Contaminants: Nitrate.
Key contaminant findings
Based on the most recent EPA sampling data for Mount Hermon's water supply.
Well within EPA limits.
Violation history
Mount Hermon's water system has 5 total violations on record, including 1 health-based violation. 3 remain unresolved. 3 violations were issued in the last 5 years.
Flood & environmental risk
Santa Cruz 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 Soquel C A Soquel, San Lorenzo R A Big Trees, San Lorenzo R A Santa Cruz.
Where does Mount Hermon's water come from?
Mount Hermon's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,176 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Soquel C A Soquel (river), San Lorenzo R A Big Trees (river), San Lorenzo R A Santa Cruz (river).
What Mount Hermon residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Mount Hermon'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.
Mount Hermon'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
Top industrial polluters within 10 miles of Mount Hermon
Industrial polluters nearby
Reported releases to surface water by facilities near Mount Hermon, ranked by pounds discharged annually.
Total reported releases to surface water: 0 lbs
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
GRANITE ROCK CO SANTA CRUZ CON SANTA CRUZ, CA95060 | Lead | 0 | 4.8 mi |
FELTON QUARRY FELTON, CA95018 | — | — | 2.5 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Mount Hermon
Superfund sites nearby
Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
- WATKINS JOHNSON CO STEWART DIVISION PLANT1.3 mi
Source: EPA Superfund National Priorities List
Flood & disaster history
Santa Cruz 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 Mount Hermon compares by contaminant
Explore where Mount Hermon ranks among all California cities for specific contaminants.
Water source & infrastructure
Where Mount Hermon's water comes from
Mount Hermon'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 1,176 people through 1 water system.
Water bodies near Mount Hermon
Mount Hermon is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Mount Hermon
| System Name | PWSID | Population | Source |
|---|---|---|---|
| MT. HERMON ASSOCIATION, INC. | CA4410008 | 1,176 | GW |
How Mount Hermon compares
Full California rankings →Mount Hermon's score of 83.5/100 is above the average of 57/100 among major California cities. It outscores 8 of 10 nearby cities.
Nearby cities
View California rankings →About Mount Hermon, CA
Learn more about your water
Guides and resources related to Mount Hermon's water quality findings.
Explore water quality across Santa Cruz
Frequently asked questions
Is Mount Hermon, CA tap water safe to drink?
Mount Hermon's water quality earned a grade of B+ (83.5/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #304 out of 694 cities tested in California.
What contaminants are in Mount Hermon's water?
Lead was measured at 0.0 ppb (90th percentile). 5 violations are on record.
How is Mount Hermon'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 Mount Hermon?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Mount Hermon's water come from?
Mount Hermon's water is sourced from Groundwater. The city has 1 water system serving approximately 1,176 residents.
What health violations has Mount Hermon's water system had?
Mount Hermon has 1 health-based violation 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. 3 violations remain unresolved.
Is Mount Hermon's groundwater at risk of contamination?
Mount Hermon 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 5 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 Mount Hermon's water compare to other cities?
Mount Hermon ranks #304 out of 694 cities in California (better than 56% of state cities) and #6410 out of 15744 cities nationally (59th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Mount Hermon's small water system affect quality?
Mount Hermon's system serves approximately 1,176 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 5 violations on record.