WaterVerge

Is Wasco, CA Tap Water Safe to Drink?

Graded B+ — but Manganese was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

28K residents served 3 water systems PWSID: CA1510021
Overall Score
83.3 / 100
Violations
7 active
Last Updated
May 2026
Source
Groundwater
#311 of 694 in California Top 41% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B+GRADE
Water Quality Grade
83.3/100
waterverge.com
B+ 83.3/100

Wasco, CA — Water Quality Report

Wasco's drinking water received a grade of B+ (83.3 out of 100), indicating good water quality. The city's 3 water systems serve approximately 27,929 residents using groundwater.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 43 violations on record, including 26 health-based violations. 7 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Wasco's water

Wasco ranks #311 out of 694 cities in California for water quality, placing it mid-range in the state.

Wasco 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.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 9.20 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.

Quality Breakdown

Water quality score

See methodology →
83.3 out of 100 Grade B+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
37.9/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
12.4/20
C
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Wasco, CA water safe to drink?

Concerns Identified

Wasco's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (83.3/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 27,929 residents using groundwater (wells).

7
Active Violations
0.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
10 events
Disaster History

Recent water quality updates for Wasco

A timeline of significant water quality events, violations, and data updates.

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Wasco's water quality assessment. Grade: B+ (83.3/100).

Disaster
TROPICAL STORM HILARY

Federal disaster declaration (FEMA DR-4750). Hurricane event — may have impacted local water infrastructure.

Disaster
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES

Federal disaster declaration (FEMA DR-3592). Flood event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Arsenic.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Arsenic.

Key contaminant findings

Based on the most recent EPA sampling data for Wasco's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 9.1000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Chromium-6 (Hexavalent Chromium) Elevated
Detected: 9.20 µg/L Limit: 10 µg/L (California MCL — no federal limit)

The "Erin Brockovich" chemical. There is no federal MCL, but California has set a limit of 10 µg/L. Reverse osmosis filtration is effective at removing hexavalent chromium.

Violation history

Wasco's water system has 43 total violations on record, including 26 health-based violations. 7 remain unresolved.

MCLMROther
Most recent violations:
Apr 2017 Arsenic Resolved
Jan 2017 Arsenic Resolved
Oct 2016 Arsenic Resolved
Jul 2016 Arsenic Resolved
Apr 2016 Arsenic Resolved

Flood & environmental risk

Kern County has experienced 10 federally declared disasters since 1967. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.

TROPICAL STORM HILARY
Hurricane FEMA DR-4750
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-3592
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA DR-4305

Where does Wasco's water come from?

Wasco's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 27,929 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Wasco residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Wasco's water.

Request your utility's CCR

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.

Monitor alerts during storms

Wasco'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.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
9.1000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
0.7 µg/L
EPA MCL: 60 µg/L · 1% of limit
Within LimitUCMR 4 DataHAA6Br: 0.6 µg/LHAA9: 0.8 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Elevated
9.20 µg/L
CA MCL (no federal MCL): 10 µg/L · 92% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
710.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 47% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Over SMCL
160.0 µg/L
EPA Secondary MCL: 50 µg/L · +20% over limit
Over SMCLUCMR 4 Data
Vanadium
Inorganic
Elevated
21.00 µg/L
EPA Short-term HA: 21 µg/L · +0% over limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Elevated
190.0 µg/L
EPA Lifetime HA: 210 µg/L · 90% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Detected
3.00 µg/L
EPA Lifetime HA: 40 µg/L · 8% of limit
DetectedUCMR 3 Data
Cobalt
Inorganic
Detected
1.20 µg/L
No federal limit: N/A µg/L · 50% of limit
DetectedNo federal MCLUCMR 3 Data
Lithium
Inorganic
Detected
9.1 µg/L
State screening level: 60 µg/L · 15% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

43
Total violations
26
Health-based
7
Active / unresolved
Apr 2017
Most recent violation
Compliance Record

Violations & advisories

43 Total
7 Active
26 Health-based
36 Resolved
Violations by category
Arsenic Rule
14
Total Coliform Rule
14
Consumer Confidence Rule
4
Stage 1 Disinfectants and Disinfection Byproducts Rule
4
Nitrate Rule
3
Jul 2009 Active
Consumer Confidence Rule
Other Violation 0
Jul 2008 Active
Consumer Confidence Rule
Other Violation 0
Jul 2007 Active
Consumer Confidence Rule
Other Violation 0
Jul 2002 Active
Consumer Confidence Rule
Other Violation 0
Jan 2001 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 1996 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Apr 2017 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Jun 2017
Jan 2017 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Mar 2017
Oct 2016 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Dec 2016
Jul 2016 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Sep 2016
Apr 2016 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Jun 2016
Jan 2016 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Mar 2016
Oct 2015 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Dec 2015
Jul 2015 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Sep 2015
Apr 2015 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Jun 2015
Jan 2015 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Mar 2015
Oct 2014 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Dec 2014
Jul 2014 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Sep 2014
Jul 2014 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Jul 2014
Showing 20 of 43 violations
Industrial pollution

Top industrial polluters within 10 miles of Wasco

Industrial polluters nearby

Reported releases to surface water by facilities near Wasco, ranked by pounds discharged annually.

FacilityTop chemicalTo surface water (lbs/yr)Distance
CERTIS USA
Chemicals · MITSUI & CO (USA) INC
WASCO, CA93280
1.9 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

10
Declared disasters
Nov 2023
Most recent
Flood
Most common type

Kern County has experienced 10 federally declared disasters since 1967. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Nov 2023
TROPICAL STORM HILARY
Hurricane FEMA #4750
Mar 2023
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #3592
Mar 2017
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA #4305
Jan 2011
SEVERE WINTER STORMS, FLOODING, AND DEBRIS AND MUD FLOWS
Flood FEMA #1952
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3248
Feb 1992
RAIN/SNOW/WIND STORMS, FLOODING, MUDSLIDES
Flood FEMA #935

Recommended water filters

Based on contaminants detected in Wasco's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 9.100 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 2.5 ppb from 1992 (2.5 ppb) to 2024 (0.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
27,929
Water Systems
3
Water Source

Where Wasco's water comes from

Groundwater

Wasco's drinking water is drawn from underground aquifers through wells.

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 local government ownership and serves approximately 27,929 people through 3 water systems.

Infrastructure

Water systems serving Wasco

System Name PWSID Population Source
WASCO, CITY OF CA1510021 22,757 GW
WASCO ST. PRISON RECEPTION CTR CA1510801 5,124 GW
POND MUTUAL WATER COMPANY CA1502620 48 GW
Regional Comparison

How Wasco compares

Full California rankings →

Wasco's score of 83.3/100 is above the average of 57/100 among major California cities. It outscores 8 of 10 nearby cities.

Wasco (this city)
83.3
Oakland
77.9
San Diego
39.7
Sacramento
31.2
California avg
57
City Profile

About Wasco, CA

Wikipedia →

Wasco is a city in the San Joaquin Valley, in Kern County, California, United States. Wasco is located 24 miles (39 km) northwest of Bakersfield, at an elevation of 328 feet (100 m). The population was 27,047 at the 2020 census, up from 25,545 at the 2010 census.

Economic Profile
$48,109
Median Income
$222,855
Median Home Value
$924/mo
Median Rent
8.6%
Unemployment
Community
30.2
Median Age
1,082
People / sq mi
5.6%
College Educated
59.7%
Homeownership
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Frequently asked questions

Is Wasco, CA tap water safe to drink?

Wasco's water quality earned a grade of B+ (83.3/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #311 out of 694 cities tested in California.

What contaminants are in Wasco's water?

Lead was measured at 0.0 ppb (90th percentile). 1 PFAS compound was detected. 43 violations are on record.

How is Wasco'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 Wasco?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Wasco's water come from?

Wasco's water is sourced from Groundwater. The city has 3 water systems serving approximately 27,929 residents.

What health violations has Wasco's water system had?

Wasco has 26 health-based violations on record. The most recent violation was recorded in April 2017. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 7 violations remain unresolved.

Is Wasco's groundwater at risk of contamination?

Wasco 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 43 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 Wasco's water compare to other cities?

Wasco ranks #311 out of 694 cities in California (better than 55% of state cities) and #6475 out of 15744 cities nationally (59th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.