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WaterVerge

Water quality report · updated Jul 2026

Is Big Pine Reservation, CA Tap Water Safe to Drink?

Graded A-, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do ↓

0 contaminants over a legal limit
1.0 ppb lead, 90th percentile · low
3 unresolved violations
600 people served by 1 water system

PWSID 090600120 · moderate data confidence · native american utility

Reviewed by WaterVerge Editorial Team · Last updated July 2026
A 85.4 / 100

#262 of 690California cities
How we grade →

01The verdict: is Big Pine Reservation water safe?

Big Pine Reservation's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (85.4/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 600 residents using groundwater (wells).

The concern

3 unresolved violations on record

EPA records show open compliance items for this system. Most are administrative, but unresolved items are worth watching.

See what was cited ↓
The good news

Lead is well under the limit

90th-percentile lead is 1.0 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.

See the trend ↓
Keep watching

5 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 ↓

Big Pine Reservation's drinking water received a grade of A- (85.4 out of 100), indicating good water quality. The city's 1 water system serves approximately 600 residents using groundwater.

Lead levels were measured at 1.0 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 18 violations on record, including 5 health-based violations. 3 remain unresolved.

Big Pine Reservation ranks #262 out of 690 cities in California for water quality, placing it mid-range in the state. Big Pine Reservation 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, Big Pine Reservation may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

How the 85.4/100 breaks down Methodology →
ViolationsHistorical violation record including health-based and monitoring violations.
35.4 / 45B
Lead & CopperLead at 1.0 ppb (90th percentile).
20 / 20A
ContaminantsPFAS + legacy contaminant analysis.
17 / 20B
ComplianceMonitoring and reporting compliance with EPA regulations.
8 / 10B
Source RiskWater source: Groundwater.
5 / 5A

02What's in Big Pine Reservation's water

Every contaminant flagged in Big Pine Reservation, 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.

1 detection · sorted by % of legal limit
Over the limit Elevated — watch Within limits
0 50% LEGAL LIMIT 150%
1 contaminant tested under EPA SDWIS, LCR and UCMR programs · 1 detected · not yet tested for PFAS under UCMR 5

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 1.0 15 ppb Inorganic Safe
Data source: EPA SDWIS, UCMR 5, local utility CCR.

03Big Pine Reservation'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 18 violations on record, including 5 health-based violations. 3 remain unresolved.

7 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.

1 health-based in 10 yrs 4 monitoring & paperwork 2 still unresolved
UpdateWater quality data updatedLatest EPA compliance and testing data incorporated into Big Pine Reservation's water quality assessment. Grade: A- (85.4/100).
Violation1 drinking water violation recorded1 health-based. Contaminants: Stage 1 Disinfectants and Disinfection Byproducts Rule.Open
Violation1 drinking water violation recordedContaminants: Chlorine.Resolved
DisasterTROPICAL STORM HILARYFederal disaster declaration (FEMA DR-4750). Hurricane event — may have impacted local water infrastructure.
DisasterSEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDESFederal disaster declaration (FEMA DR-3592). Flood event — may have impacted local water infrastructure.
Violation3 drinking water violations recordedContaminants: Public Notice, Nitrite, Nitrate.Open
Lead, 90th percentileppb · lower is better
0102030EPA action level · 15 ppb1997 — 5 ppb1998 — 4.5 ppb1999 — 2 ppb2000 — 23 ppb2004 — 2.5 ppb2007 — 1 ppb2010 — 1 ppb2013 — 5 ppb2016 — 1 ppb2019 — 1 ppb2022 — 1 ppb2025 — 1 ppb5119972000201020192025

Down 4 ppb since 1997. Latest reading: 1 ppb (2025) — 7% of the action level. Sampled at higher-risk homes (90th percentile).

04Where Big Pine Reservation's water comes from

Big Pine Reservation's drinking water is drawn from underground aquifers through wells.

Source

Groundwater

Underground aquifers reached by wells — naturally filtered, but can carry minerals like arsenic and nitrate.

Treatment

Local treatment

Groundwater generally needs less treatment — typically disinfection and, where needed, mineral removal.

Distribution

1 system

1 water system, operated under native american ownership.

Delivery

600 people

Residents served across Big Pine Reservation's service area.

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 native american ownership and serves approximately 600 people through 1 water system.

System namePWSIDPopulationSource
Big Pine Paiute Band 090600120 600 Groundwater

05Pressure on Big Pine Reservation'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

Recurring — declared disasters

9 federal disaster declarations on record for Inyo County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.

TROPICAL STORM HILARY Nov 2023 · DR-4750
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES Mar 2023 · DR-3592
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES Jan 2023 · DR-4683

06How Big Pine Reservation compares

Scores for nearby California cities on one line, with the average marked.

Big Pine Reservation (this city)
85.4 · A-
Oakland
77.9 · B
Los Angeles
42.8 · F
San Diego
39.7 · F
Sacramento
31.2 · F
San Jose
28 · F

dashed line = California average (57/100)

Big Pine Reservation scores 85.4/100above the California average of 57/100. It outscores 8 of 10 nearby cities. Full California rankings →

07What to do at home

Steps matched to what testing actually found in Big Pine Reservation's water — not generic advice.

Extra protection

A basic carbon filter still helps

Big Pine Reservation's water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.

Compare tested filters →
Know your report

Read your utility's annual report

Every utility must publish a yearly Consumer Confidence Report with its own testing results. It pairs well with the independent data on this page.

How to read a CCR →
Stay informed

Watch for Big Pine Reservation 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 Big Pine Reservation, CA tap water safe to drink?

Big Pine Reservation's water quality earned a grade of A- (85.4/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #262 out of 690 cities tested in California.

What contaminants are in Big Pine Reservation's water?

Lead was measured at 1.0 ppb (90th percentile). 18 violations are on record.

How is Big Pine Reservation'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 Big Pine Reservation?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Big Pine Reservation's water come from?

Big Pine Reservation's water is sourced from Groundwater. The city has 1 water system serving approximately 600 residents.

What health violations has Big Pine Reservation's water system had?

Big Pine Reservation has 5 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. 3 violations remain unresolved.

Is Big Pine Reservation's groundwater at risk of contamination?

Big Pine Reservation 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 18 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 Big Pine Reservation's water compare to other cities?

Big Pine Reservation ranks #262 out of 690 cities in California (better than 62% of state cities) and #5324 out of 15382 cities nationally (65th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Big Pine Reservation's small water system affect quality?

Big Pine Reservation's system serves approximately 600 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 18 violations on record.

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About Big Pine Reservation, CA: Big Pine is a census-designated place (CDP) in Inyo County, California, United States. Big Pine is located approximately 15 miles (24 km) south-southeast of Bishop. Its population was 1,875 at the 2020 census, up from 1,756 at the 2010 census. The Big Pine Band of Owens Valley Paiute Shoshone Indians of the Big Pine Reservation bases their tribal headquarters there. Median household income $62,576 · median home value $297,986 · median age 49.3 · 75.1% homeowners · 16.5% college educated. Wikipedia → Sources: EPA SDWIS & ECHO · UCMR 3–5 · Lead & Copper Rule samples · EPA TRI · U.S. Drought Monitor · FEMA declarations. Data last updated Jul 2026. Analysis by the WaterVerge Editorial Team · methodology.