Is Plymouth, CA Tap Water Safe to Drink?
Graded B — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
77.9/100
waterverge.com Plymouth, CA — Water Quality Report
Plymouth's drinking water received a grade of B (77.9 out of 100), indicating good water quality. The city's 3 water systems serve approximately 1,399 residents using purchased surface water.
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 47 violations on record, including 6 health-based violations. 9 remain unresolved.
What to know about Plymouth's water
Plymouth ranks #414 out of 694 cities in California for water quality, placing it below average 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.
As a small community water system, Plymouth may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Plymouth, CA water safe to drink?
Plymouth's drinking water has significant quality concerns based on EPA testing data. With a grade of B (77.9/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 1,399 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Plymouth
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Plymouth's water quality assessment. Grade: B (77.9/100).
Contaminants: LEAD AND COPPER RULE REVISIONS, Consumer Confidence 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.
Contaminants: Lead and Copper Rule.
1 health-based. Contaminants: TTHM.
Key contaminant findings
Based on the most recent EPA sampling data for Plymouth's water supply.
Well within EPA limits.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Plymouth's water system has 47 total violations on record, including 6 health-based violations. 9 remain unresolved. 4 violations were issued in the last 5 years.
Flood & environmental risk
Amador County has experienced 7 federally declared disasters since 1964. 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 Plymouth's water come from?
Plymouth's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 3 water systems serving approximately 1,399 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment.
What Plymouth residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Plymouth'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.
Plymouth'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
Superfund sites within 10 miles of Plymouth
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.
- ARGONAUT MINE9.0 mi
Source: EPA Superfund National Priorities List
Flood & disaster history
Amador County has experienced 7 federally declared disasters since 1964. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Plymouth's water supply, we recommend the following filter types.
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 |
| 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. | 1.40 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level (90th percentile)
Latest reading: 1.400 mg/L (2017)
EPA action level: 1.3 mg/L
See how Plymouth compares by contaminant
Explore where Plymouth ranks among all California cities for specific contaminants.
Water source & infrastructure
Where Plymouth's water comes from
Plymouth's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
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 local government ownership and serves approximately 1,399 people through 3 water systems.
Water systems serving Plymouth
| System Name | PWSID | Population | Source |
|---|---|---|---|
| PLYMOUTH, CITY OF | CA0310004 | 1,060 | SWP |
| HOPE FOUNDATION/MORIAH HEIGHTS | CA0300062 | 299 | GW |
| IONE BAND OF MIWOK INDIANS | CA0300078 | 40 | GW |
How Plymouth compares
Full California rankings →Plymouth's score of 77.9/100 is above the average of 57/100 among major California cities. It outscores 7 of 10 nearby cities.
Nearby cities
View California rankings →About Plymouth, CA
Learn more about your water
Guides and resources related to Plymouth's water quality findings.
Explore water quality across Amador
Frequently asked questions
Is Plymouth, CA tap water safe to drink?
Plymouth's water quality earned a grade of B (77.9/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #414 out of 694 cities tested in California.
What contaminants are in Plymouth's water?
Lead was measured at 0.0 ppb (90th percentile). 47 violations are on record.
How is Plymouth'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 Plymouth?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Plymouth's water come from?
Plymouth's water is sourced from Purchased surface water. The city has 3 water systems serving approximately 1,399 residents.
What health violations has Plymouth's water system had?
Plymouth has 6 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. 9 violations remain unresolved.
How does Plymouth's water compare to other cities?
Plymouth ranks #414 out of 694 cities in California (better than 40% of state cities) and #8860 out of 15744 cities nationally (44th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.