01The verdict: is Carmel Valley water safe?
Carmel Valley's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (68/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 6 water systems serve approximately 504 residents using surface water (rivers, lakes, or reservoirs).
Copper is over its legal limit
Measured at 6.32 mg/L against the EPA Action Level of 1.3 mg/L. The ledger below shows how far over — and which filter removes it.
See the measurement ↓Lead is well under the limit
90th-percentile lead is 3.7 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.
See the trend ↓6 violations in the last five years
Recent compliance history is the best predictor of future problems — the year-by-year record is below.
See the record ↓Carmel Valley's drinking water received a grade of C+ (68 out of 100), indicating fair water quality. The city's 6 water systems serve approximately 504 residents using surface water.
Lead levels were measured at 3.7 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 139 violations on record, including 45 health-based violations. 11 remain unresolved.
Carmel Valley ranks #525 out of 690 cities in California for water quality, placing it among the lowest-rated in the state. The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection. Hexavalent chromium (chromium-6) was detected at 0.03 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration. As a small community water system, Carmel Valley 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.
02What's in Carmel Valley's water
Every contaminant flagged in Carmel Valley, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.
Over Limit — EPA Action Level: 1.3 mg/L
Exceeds the EPA action level. Copper leaches from household plumbing — flush taps for 30 seconds before drinking, and consider a certified filter.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. | 3.7 | 15 | ppb | Inorganic | Safe |
| Copper (90th percentile) CopperInorganic A metal that enters drinking water mainly through corrosion of copper plumbing. Small amounts are essential for health, but excess levels are harmful. Health EffectsGastrointestinal distress (nausea, vomiting, diarrhea) at short-term high levels; liver and kidney damage from long-term exposure. EPA Limit1.3 mg/L action level Common SourcesCorrosion of copper household plumbing, erosion of natural deposits. | 6.32 | 1.3 | mg/L | Inorganic | Over Limit |
Cities ranked by 90th-percentile lead PF PFAS in California
Cities ranked by compounds detected Cu Copper in California
Cities ranked by 90th-percentile copper
03Carmel Valley's ten-year track record
Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 139 violations on record, including 45 health-based violations. 11 remain unresolved.
5 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.
▲ Up 3.7 ppb since 2011. Latest reading: 3.7 ppb (2027) — 25% of the action level. Sampled at higher-risk homes (90th percentile).
▲ Up 4.2 mg/L since 2020. The latest reading (6.3 mg/L, 2025) is over the action level. Sampled at higher-risk homes (90th percentile).
04Where Carmel Valley's water comes from
Carmel Valley's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface Water
Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.
Local treatment
Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.
6 systems
6 water systems, operated under private ownership.
504 people
Residents served across Carmel Valley's service area.
Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards. These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge. The system is operated by private ownership and serves approximately 504 people through 6 water systems.
| System name | PWSID | Population | Source |
|---|---|---|---|
| TASSAJARA SPRINGS WS | CA2701705 | 150 | Surface Water |
| ASOLEADO MWC | CA2702148 | 101 | Groundwater |
| TULARCITOS MWC | CA2701800 | 90 | Groundwater |
| WOODSIDE WA | CA2702140 | 73 | Groundwater |
| CACHAGUA MUTUAL WS (#4) | CA2701888 | 55 | Groundwater |
| OUTLOOK WA | CA2700622 | 35 | Groundwater |
Water bodies near Carmel Valley
As a surface-water system, these water bodies may directly influence Carmel Valley's drinking water supply.
05Pressure on Carmel Valley's watershed
Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.
Flood & storm history
10 federal disaster declarations on record for Monterey County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.
06How Carmel Valley compares
Scores for nearby California cities on one line, with the average marked.
dashed line = California average (57/100)
Carmel Valley scores 68/100 — above the California average of 57/100. It outscores 6 of 10 nearby cities. Full California rankings →
42.8 / 100FSan Jose, CA
28 / 100BOakland, CA
77.9 / 100FSan Diego, CA
39.7 / 100FSacramento, CA
31.2 / 100ABurlingame, CA
89.2 / 100
Compare all cities in the county — grades, violations, and contaminant data side by side.→
07What to do at home
Steps matched to what testing actually found in Carmel Valley's water — not generic advice.
Filter drinking & cooking water
NSF-certified water filter. Copper exceeds the EPA action level of 1.3 mg/L
Compare tested filters →Flush taps & check your service line
Lead leaches from pipes as water sits. Run cold water 30 seconds before drinking (especially mornings), and ask the utility whether your address still has a lead service line.
Lead risks explained →Watch for Carmel Valley alerts
This area has a history of flood declarations — after severe weather, watch for boil-water advisories from the utility, and check the live alerts on this page.
All water alerts →Frequently asked questions
Is Carmel Valley, CA tap water safe to drink?
Carmel Valley's water quality earned a grade of C+ (68/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #525 out of 690 cities tested in California.
What contaminants are in Carmel Valley's water?
Lead was measured at 3.7 ppb (90th percentile). 139 violations are on record.
How is Carmel Valley'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 Carmel Valley?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Carmel Valley's water come from?
Carmel Valley's water is sourced from Surface water. The city has 6 water systems serving approximately 504 residents.
What health violations has Carmel Valley's water system had?
Carmel Valley has 45 health-based violations on record. The most recent violation was recorded in January 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 11 violations remain unresolved.
How does Carmel Valley's water compare to other cities?
Carmel Valley ranks #525 out of 690 cities in California (better than 24% of state cities) and #10983 out of 15382 cities nationally (29th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.