PlainWater

LA COSTA WATER USERS ASSOC

PWS ID: AZ0402041 · DOUGLAS, Arizona 85607

LA COSTA WATER USERS ASSOC serves 30 people in DOUGLAS, Arizona using Groundwater water sources. It has 113 recorded EPA violations, including 8 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: LA COSTA WATER USERS ASSOC

LA COSTA WATER USERS ASSOC is a public/private-owned community water system that delivers drinking water to 30 residents in DOUGLAS, Arizona (Cochise County) through 16 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 113 total violations for this system , of which 8 (7%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 62 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Consumer Confidence Rule, recorded in 34 violations (Other). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Arizona, EPA tracks 1,493 public water systems serving 7,322,166 people, with 228,944 cumulative violations and 15,663 health-based violations on record. About 98% of systems in the state carry at least one violation, and state-wide the average per system is 153.3 violations. LA COSTA WATER USERS ASSOC's 113 violations sit below the Arizona average. Statewide, 145 of 152 UCMR5-tested systems have reported PFAS detections (95.4%). All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
30
Total Violations
113
Health-Based Violations
8
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Public/Private
Connections
16
County
Cochise
School/Daycare
No
MCL Violations
0
Monitoring Violations
62
Treatment Tech Violations
8

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Consumer Confidence Rule Other 34 2025
Coliform (TCR) MR 16 2014
Lead and Copper Rule MR 8 2021
E. COLI MR 5 2022
Revised Total Coliform Rule TT 4 2022
Groundwater Rule TT 4 2023
Nitrate MR 3 2000
Chlorine MR 2 2008
Revised Total Coliform Rule RPT 2 2020
Public Notice Other 2 2021
1,2,4-Trichlorobenzene MR 1 1998
cis-1,2-Dichloroethylene MR 1 1998
DICHLOROMETHANE MR 1 1998
o-Dichlorobenzene MR 1 1998
p-Dichlorobenzene MR 1 1998
trans-1,2-Dichloroethylene MR 1 1998
1,2-Dichloroethane MR 1 1998
1,2-Dichloropropane MR 1 1998
1,1,2-Trichloroethane MR 1 1998
Tetrachloroethylene MR 1 1998
CHLOROBENZENE MR 1 1998
Benzene MR 1 1998
Toluene MR 1 1998
Styrene MR 1 1998
Arsenic MR 1 1990
Fluoride MR 1 1990
Chromium MR 1 1990
Cadmium MR 1 1990
Gross Alpha, Excl. Radon and U MR 1 1988
Barium MR 1 1990

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records — or to file a complaint, request a Consumer Confidence Report, or check current monitoring status — go directly to the federal and state regulators that enforce the Safe Drinking Water Act for LA COSTA WATER USERS ASSOC.

Federal Source of Truth

EPA SDWIS — Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID AZ0402041 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Arizona Drinking Water Authority

Arizona DEQ — Drinking Water Program is the primacy agency that licenses and inspects LA COSTA WATER USERS ASSOC under EPA-delegated authority.

Open AZ regulator portal

Source: Arizona DEQ — Drinking Water Program

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2025 Consumer Confidence Rule Other 34 SDWIS / AZ0402041 / 7000
2023 Groundwater Rule TT 4 SDWIS / AZ0402041 / 0700
2022 E. COLI MR 5 SDWIS / AZ0402041 / 3014
2022 Revised Total Coliform Rule TT 4 SDWIS / AZ0402041 / 8000
2021 Lead and Copper Rule MR 8 SDWIS / AZ0402041 / 5000
2021 Public Notice Other 2 SDWIS / AZ0402041 / 7500
2020 Revised Total Coliform Rule RPT 2 SDWIS / AZ0402041 / 8000
2014 Coliform (TCR) MR 16 SDWIS / AZ0402041 / 3100
2008 Chlorine MR 2 SDWIS / AZ0402041 / 0999
2000 Nitrate MR 3 SDWIS / AZ0402041 / 1040
1998 1,2,4-Trichlorobenzene MR 1 SDWIS / AZ0402041 / 2378
1998 cis-1,2-Dichloroethylene MR 1 SDWIS / AZ0402041 / 2380
1998 DICHLOROMETHANE MR 1 SDWIS / AZ0402041 / 2964
1998 o-Dichlorobenzene MR 1 SDWIS / AZ0402041 / 2968
1998 p-Dichlorobenzene MR 1 SDWIS / AZ0402041 / 2969

How LA COSTA WATER USERS ASSOC Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric LA COSTA WATER USERS ASSOC Arizona avg Federal benchmark
Total violations 113 153.3 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 8 10.5 Indicates a contaminant exceeded a federal MCL
PFAS detection None 95.4% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 30 4,904 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 1,493 regulated public water systems in Arizona.

Federal MCL reference — Safe Drinking Water Act thresholds
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is LA COSTA WATER USERS ASSOC water safe to drink?
LA COSTA WATER USERS ASSOC (PWS ID: AZ0402041) has 113 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 30 people using Groundwater sources.
How many people does LA COSTA WATER USERS ASSOC serve?
LA COSTA WATER USERS ASSOC serves 30 people in DOUGLAS, Arizona. It is a Public/Private-owned system using Groundwater water sources with 16 service connections.
What type of violations does LA COSTA WATER USERS ASSOC have?
LA COSTA WATER USERS ASSOC has 113 total violations: 8 health-based violations (MCL exceedances or treatment failures), 62 monitoring/reporting violations, and 8 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in LA COSTA WATER USERS ASSOC water?
No PFAS testing data is available for LA COSTA WATER USERS ASSOC under the EPA's UCMR5 monitoring program.
What water source does LA COSTA WATER USERS ASSOC use?
LA COSTA WATER USERS ASSOC uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from?
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.

Explore PlainWater

Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Related

Data sourced from $official public datasets. See our methodology for details. Retrieved and formatted by PlainWater Editorial