A
97

Excellent Water Quality

Claremont, CA 91711

Los Angeles County · Population served: 1,789 · Data updated March 2026

Water Systems Serving This Area

🌊
OWENS VALLEY WATER RESOURCES, INC.
Groundwater · Pop. 311
PWSID: CA1400005
🏔
THREE VALLEYS MWD
Surface water · Pop. 0
PWSID: CA1910041
🌊
SIERRA WATER RESOURCES - SIERRA CITY
Groundwater · Pop. 324
PWSID: CA4600017
🏔
SONORA WATER RESOURCES, INC
Surface water · Pop. 1,154
PWSID: CA5510024

Contaminants Detected

ContaminantDetected LevelEPA MCLHealth GuidelineStatus
Lead
3.9
15 ppb 1 ppb Warning

Water Quality Summary

Understanding Your Water in Claremont

Tap water quality in Claremont, California (91711) receives an overall grade of A (Excellent) with a score of 97 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is 16 points above the California state average of 81. Compared to the national average (75), this area performs significantly better. The area is served by 4 water systems providing water to approximately 1,789 people, using surface water and groundwater sources. Testing has found elevated levels of Lead that warrant attention. The area has a clean violation record over the past 5 years — a positive indicator of consistent water quality management.

Your Score 97/100 A
vs State 16 pts above California avg (81)
vs National 22 pts above national avg (75)

What a Grade A Means

A score of 97/100 means the water supply in Claremont, CA meets or exceeds all EPA standards with minimal issues. Contaminant levels are well within safe limits, and the water system has maintained a strong compliance record. While no water supply is guaranteed perfect at the tap due to household plumbing, this is among the best-scoring areas in the country.

Surface water: sourced from rivers, lakes, or reservoirs
Groundwater: drawn from underground aquifers via wells

Health Information

What These Contaminants Mean for You

⚠️

Lead in Your Water

Lead is a toxic metal that can leach from aging pipes and plumbing fixtures.

Health Effects

Even low levels of lead exposure can cause developmental delays in children, kidney damage, and cardiovascular effects in adults. The EPA action level is 15 ppb, but health experts recommend no safe level of lead in drinking water.

Common Sources

Lead enters water primarily through corrosion of lead service lines, lead solder, and brass fixtures — especially in homes built before 1986.

What You Can Do

If lead is detected above 1 ppb, consider using a certified lead-removal filter (NSF/ANSI 53) for drinking and cooking water. Run cold water for 30 seconds before use if water has been sitting in pipes.

Common Questions

Frequently Asked Questions

Based on EPA data, tap water in Claremont, California receives a grade of A (Excellent) with a score of 97/100. This indicates the water meets federal standards and has relatively few concerns. However, individual homes may still have localized issues such as lead from old plumbing.

ZIP code 91711 is served by 4 water systems using surface water, groundwater sources, providing water to approximately 1,789 people. Multiple source types mean your water may come from a blend of surface and underground sources.

Lead was detected at 3.9 ppb in Claremont, California. While this is below the EPA action level of 15 ppb, it exceeds the health guideline of 1 ppb recommended by health organizations. Consider a certified lead filter, especially if you have young children.

No PFAS ("forever chemicals") were detected in water systems serving Claremont, California during the most recent EPA monitoring period (UCMR5). However, not all water systems have been tested for all PFAS compounds, and new contamination can occur over time.

Water systems serving Claremont, California have zero violations in the last 5 years. This is a positive indicator of consistent regulatory compliance and water quality management.

Based on detected contaminants (lead), residents in Claremont, California should consider: NSF/ANSI 53 certified filter — specifically rated for lead reduction. Pitcher filters (like Brita Longlast or PUR) and under-sink systems both work. Always look for filters with NSF/ANSI certification for the specific contaminants you want to remove.

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