California · drinking water · SDWIS through latest publish

Winterhaven County Water District Water Quality — Winterhaven, California

PWSID CA1300009 · GroundwaterMunicipal

394 people served. 1 health-based SDWIS violation recorded in the past 5 years. 2 remain unresolved. Last cited 2 years ago.

ALL SDWIS VIOLATIONS · 20222026 (annual count)
Bar chart of annual values from 2022 to 2026, in violations. Most recent year (2026): 0 violations.22 violations'22'23'24'25'260 violations
Anomaly engine

Active signals

UNRESOLVED VIOLATION · SDWIS VIOLATION

Contaminant 5200

Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2024 (contaminant 5200).

EPA SDWIS record

UNRESOLVED VIOLATION · SDWIS VIOLATION

Contaminant 5200

Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2024 (contaminant 5200).

EPA SDWIS record

Most-cited contaminants

What This Utility Gets Cited For

  • Total Trihalomethanes (TTHM)7 citations
  • Haloacetic Acids (HAA5)7 citations
  • Beryllium6 citations
  • Contaminant 52002 citations
  • Contaminant 20632 citations
Violation history

What's On The SDWIS Record

Health-based violations exceed an MCL or treatment-technique standard. Monitoring violations are reporting failures with no measured exceedance — they tell you the system isn't fully transparent, not that the water is unsafe today.

HEALTH-BASED · CONTAMINANT 5200UNRESOLVED

2024 · Contaminant 5200 · Phase I/II/V Inorganic Chemical Rules

Treatment technique violation

CONTAMINANT CODE 5200

MONITORING · CONTAMINANT 5200UNRESOLVED

2024 · Contaminant 5200 · Phase I/II/V Inorganic Chemical Rules

Reporting failure

CONTAMINANT CODE 5200

MONITORING · TOTAL TRIHALOMETHANES (TTHM)

2022 · Total Trihalomethanes (TTHM) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2950

MONITORING · TOTAL TRIHALOMETHANES (TTHM)

2022 · Total Trihalomethanes (TTHM) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2950

MONITORING · TOTAL TRIHALOMETHANES (TTHM)

2022 · Total Trihalomethanes (TTHM) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2950

MONITORING · TOTAL TRIHALOMETHANES (TTHM)

2022 · Total Trihalomethanes (TTHM) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2950

MONITORING · TOTAL TRIHALOMETHANES (TTHM)

2022 · Total Trihalomethanes (TTHM) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2950

MONITORING · TOTAL TRIHALOMETHANES (TTHM)

2022 · Total Trihalomethanes (TTHM) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2950

MONITORING · TOTAL TRIHALOMETHANES (TTHM)

2022 · Total Trihalomethanes (TTHM) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2950

MONITORING · HALOACETIC ACIDS (HAA5)

2022 · Haloacetic Acids (HAA5) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2456

MONITORING · HALOACETIC ACIDS (HAA5)

2022 · Haloacetic Acids (HAA5) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2456

MONITORING · HALOACETIC ACIDS (HAA5)

2022 · Haloacetic Acids (HAA5) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2456

MONITORING · HALOACETIC ACIDS (HAA5)

2022 · Haloacetic Acids (HAA5) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2456

MONITORING · HALOACETIC ACIDS (HAA5)

2022 · Haloacetic Acids (HAA5) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2456

MONITORING · HALOACETIC ACIDS (HAA5)

2022 · Haloacetic Acids (HAA5) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2456

MONITORING · HALOACETIC ACIDS (HAA5)

2022 · Haloacetic Acids (HAA5) · Total Trihalomethanes Rule

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2456

MONITORING · BERYLLIUM

2022 · Beryllium · Phase I/II/V Inorganic Chemical Rules

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 1040

MONITORING · BERYLLIUM

2022 · Beryllium · Phase I/II/V Inorganic Chemical Rules

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 1040

MONITORING · BERYLLIUM

2022 · Beryllium · Phase I/II/V Inorganic Chemical Rules

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 1040

MONITORING · BERYLLIUM

2022 · Beryllium · Phase I/II/V Inorganic Chemical Rules

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 1040

MONITORING · BERYLLIUM

2022 · Beryllium · Phase I/II/V Inorganic Chemical Rules

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 1040

MONITORING · BERYLLIUM

2022 · Beryllium · Phase I/II/V Inorganic Chemical Rules

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 1040

MONITORING · CONTAMINANT 2063

2022 · Contaminant 2063 · Nitrate/Nitrite

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2063

MONITORING · CONTAMINANT 2063

2022 · Contaminant 2063 · Nitrate/Nitrite

Failure to monitor as scheduled; returned to compliance

CONTAMINANT CODE 2063

Equity context · ACS 2018-2022 · USEPA-clone EJ disparity

Who Drinks This Water

Imperial County, California (utility's served county per SDWIS GEOGRAPHIC_AREA — city-level not yet matched): a service population of 179,578. Local disparity score for pm2.5 (fine particulate) sits severely above the reference burden (222). Why we surface this →

POPULATION SHARE
21.1%

Low-income

POPULATION SHARE
90.4%

People of color

POPULATION SHARE
7.4%

Under age 5

POPULATION SHARE
13.2%

Over age 64

NATIONAL PERCENTILE · vs all US block groups (population-weighted; ranked against the national EJScreen indicator distribution)

  • PM2.5 (fine particulate)Health riskFine inhalable particles 2.5 micrometers or smaller. They travel deep into the lungs and into the bloodstream — linked to asthma, heart disease, stroke, and premature death.88in the highest 20% nationally
  • OzoneHealth riskGround-level ozone (smog) inflames the airways. Even short exposures trigger asthma attacks and worsen chronic lung and heart disease.64above the national median
  • Nitrogen dioxide (NO₂)Health riskA tailpipe and combustion gas. Concentrates near busy roads and industrial sites; raises risk of airway inflammation, asthma, and lower respiratory infections in children.60above the national median
  • Diesel particulateHealth riskSoot from diesel engines (trucks, trains, ports, construction). EPA classifies it as a likely human carcinogen and a major driver of childhood asthma near freight corridors.56near the national median
  • Toxic releases (RSEI)Health riskEPA's Risk-Screening Environmental Indicators score — weights TRI chemical releases by toxicity, where they go, and how many people are nearby. Higher means greater modeled cancer and chronic-health risk.40near the national median
  • Traffic proximityHealth riskPopulation-weighted distance to high-volume roads. Living close to heavy traffic raises exposure to PM2.5, NO₂, and diesel exhaust — and the cardiovascular and asthma risks that follow.47near the national median
  • Lead-paint risk (pre-1960 housing)Health riskShare of housing built before 1960, when lead-based paint was common. Dust from deteriorating paint is the leading cause of childhood lead poisoning, which permanently impairs cognitive development.50near the national median
  • Superfund site proximityHealth riskPopulation-weighted distance to NPL Superfund sites — the most contaminated waste sites in the country. Nearby groundwater, soil, and air can carry industrial solvents, metals, and other long-lived contaminants.56near the national median
  • RMP-facility proximityHealth riskDistance to facilities holding chemicals at quantities large enough to require an EPA Risk Management Plan (refineries, fertilizer plants, etc.). These pose acute exposure risk during accidental releases.88in the highest 20% nationally
  • Hazardous-waste site proximityHealth riskDistance to RCRA hazardous-waste handlers (treatment, storage, disposal facilities). Indicates potential exposure to industrial chemicals in air, soil, and groundwater.50near the national median
  • Underground storage tanksHealth riskDensity of underground tanks (gasoline, heating oil, industrial fluids). Leaking tanks are a leading source of benzene and other volatile organic compounds in groundwater drinking-water supplies.28below the national median
  • NPDES wastewater proximityHealth riskDistance to permitted industrial wastewater dischargers. Closer proximity raises exposure to pollutants released into surface waters used for fishing, recreation, and downstream drinking-water intakes.99in the highest 5% nationally
  • Drinking-water non-complianceHealth riskEPA score for public water systems with health-based Safe Drinking Water Act violations. Higher means more residents on systems that recently exceeded safe limits for contaminants like lead, arsenic, or nitrate.76above the national median
EJ disparity scores · service-area block groups (100 = national reference; higher = greater disparate burden)
IndicatorDisparity scoreReading
PM2.5 (fine particulate)222severely above the reference burden
Ozone208severely above the reference burden
Nitrogen dioxide (NO₂)150moderately above the reference
Diesel particulate134moderately above the reference
Toxic releases (RSEI)13well below the reference
Traffic proximity109near the reference
Lead-paint risk (pre-1960 housing)93near the reference
Superfund site proximity51below the reference
RMP-facility proximity201severely above the reference burden
Hazardous-waste site proximity111moderately above the reference
Underground storage tanks0well below the reference
NPDES wastewater proximity164well above the reference burden
Drinking-water non-compliance9well below the reference

Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).

Source. EPA Safe Drinking Water Information System · retrieved 2026-05-07. Reporting period 2022-01-012026-05-07.

What this is not. SDWIS records compliance against federal MCLs — not a direct readout of tap-water concentrations. Active health-based violations are not the same as a current crisis; we link to the EPA record so you can verify return-to-compliance status before forming a conclusion.