Is Twin Peaks, 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 ↓
76.8/100
waterverge.com Twin Peaks, CA — Water Quality Report
Twin Peaks's drinking water received a grade of B (76.8 out of 100), indicating good water quality. The city's 2 water systems serve approximately 2,915 residents using purchased surface water.
Lead levels were measured at 9.3 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 11 violations on record, including 3 health-based violations. 4 remain unresolved.
What to know about Twin Peaks's water
Twin Peaks ranks #429 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.
While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.
As a small community water system, Twin Peaks may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Twin Peaks, CA water safe to drink?
Twin Peaks's drinking water has significant quality concerns based on EPA testing data. With a grade of B (76.8/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 2,915 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Twin Peaks
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Twin Peaks's water quality assessment. Grade: B (76.8/100).
Contaminants: Lead and Copper Rule.
Federal disaster declaration (FEMA DR-3592). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3591). Flood event — may have impacted local water infrastructure.
Contaminants: Nitrate.
Contaminants: Nitrite.
Key contaminant findings
Based on the most recent EPA sampling data for Twin Peaks's water supply.
Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Twin Peaks's water system has 11 total violations on record, including 3 health-based violations. 4 remain unresolved. 2 violations were issued in the last 5 years.
Flood & environmental risk
San Bernardino 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 Deep C Nr Hesperia, Wf Mojave R Ab Mojave R Forks Res Nr Hesperia, Santa Ana R Nr Mentone (River Only), Sar Supp Gage Nr Mentone, Plunge C Nr East Highlands.
Where does Twin Peaks's water come from?
Twin Peaks's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 2 water systems serving approximately 2,915 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Deep C Nr Hesperia (river), Wf Mojave R Ab Mojave R Forks Res Nr Hesperia (river), Santa Ana R Nr Mentone (River Only) (river), Sar Supp Gage Nr Mentone (river), Plunge C Nr East Highlands (river).
What Twin Peaks residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Twin Peaks'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.
Twin Peaks'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
Drought conditions
D1 — moderate droughtSan Bernardino County is currently in D1 (moderate drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Flood & disaster history
San Bernardino 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.
Recommended water filters
Based on contaminants detected in Twin Peaks'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. | 9.3 | 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. | 1.76 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level trend (90th percentile)
See how Twin Peaks compares by contaminant
Explore where Twin Peaks ranks among all California cities for specific contaminants.
Water source & infrastructure
Where Twin Peaks's water comes from
Twin Peaks'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 private ownership and serves approximately 2,915 people through 2 water systems.
Water bodies near Twin Peaks
Twin Peaks is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.
Water systems serving Twin Peaks
| System Name | PWSID | Population | Source |
|---|---|---|---|
| ALPINE WATER USERS ASSOCIATION | CA3610002 | 2,534 | SWP |
| STRAWBERRY LODGE MWC | CA3600301 | 381 | GW |
How Twin Peaks compares
Full California rankings →Twin Peaks's score of 76.8/100 is above the average of 57/100 among major California cities. It outscores 7 of 10 nearby cities.
Nearby cities
View California rankings →Learn more about your water
Guides and resources related to Twin Peaks's water quality findings.
Explore water quality across San Bernardino
Frequently asked questions
Is Twin Peaks, CA tap water safe to drink?
Twin Peaks's water quality earned a grade of B (76.8/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #429 out of 694 cities tested in California.
What contaminants are in Twin Peaks's water?
Lead was measured at 9.3 ppb (90th percentile). 11 violations are on record.
How is Twin Peaks'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 Twin Peaks?
While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Twin Peaks's water come from?
Twin Peaks's water is sourced from Purchased surface water. The city has 2 water systems serving approximately 2,915 residents.
What health violations has Twin Peaks's water system had?
Twin Peaks has 3 health-based violations on record. The most recent violation was recorded in January 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 4 violations remain unresolved.
How does Twin Peaks's water compare to other cities?
Twin Peaks ranks #429 out of 694 cities in California (better than 38% of state cities) and #9183 out of 15744 cities nationally (42th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.