Maysville
Community water system in Garvin County, Oklahoma, serving 1,212 people from surface water. 8 rules violated in the past three years, 3 still unresolved. Owned by local government.
Quarterly compliance history
2023
2023
2024
2024
2024
2024
2025
2025
2025
2025
2026
2026
2026
Currently in violation
EPA data updated Oct 7, 2026
Stage 2 Disinfectants and Disinfection Byproducts Rule
Maximum Contaminant Level ViolationMonitoring and Reporting
Health-based
43 violations, May 2023 to open · 2 contaminants · 33 measured values
Stage 2 Disinfectants and Disinfection Byproducts Rule
Maximum Contaminant Level ViolationMonitoring and Reporting Health-based43 violations, May 2023 to open · 2 contaminants · 33 measured values
Monitoring and Reporting: 10 violations, 4 still open, May 2023 to open. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.
Maximum Contaminant Level Violation, health-based: 33 violations, Jul 2023 to Jun 2026. A sample exceeded the maximum contaminant level EPA allows in drinking water.
Limit 0.08 MG/L · Apr to Jun 2026
Limit 0.08 MG/L · Apr to Jun 2026
Limit 0.06 MG/L · Apr to Jun 2026
Limit 0.08 MG/L · Jan to Mar 2026
Limit 0.08 MG/L · Jan to Mar 2026
Limit 0.06 MG/L · Jan to Mar 2026
27 more in EPA's record
Contaminants on the record: Total Haloacetic Acids (HAA5), TTHM (Total Trihalomethanes).
Total Haloacetic Acids (HAA5), health effects: Dichloroacetic acid is a probable human carcinogen (Group B2). Long-term exposure to trichloroacetic acid may also increase cancer risk. Animal studies show liver, kidney, and reproductive effects at high doses. Limit: 0.060 mg/L (60 ppb) locational running annual average (LRAA)
TTHM (Total Trihalomethanes), health effects: Long-term exposure is associated with increased bladder cancer risk. Some studies link high TTHM exposure to adverse reproductive outcomes. Bromodichloromethane is classified as a possible human carcinogen. Limit: 0.080 mg/L (80 ppb) locational running annual average (LRAA)
Lead and Copper Rule
Monitoring and Reporting
1 violation, Oct 2025 to open
Lead and Copper Rule
Monitoring and Reporting1 violation, Oct 2025 to open
Monitoring and Reporting: 1 violation, open since Oct 2025. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.
What the rule requires: The 1991 LCR uses action levels rather than MCLs: if the 90th percentile of high-risk tap samples exceeds 15 ppb lead or 1.3 mg/L copper, the system must take escalating corrective actions. Violations typically indicate failure to maintain adequate corrosion control — the treatment that keeps lead from leaching out of pipes, solder, and fixtures.
About this rule
Public Notice Rule and Revised PN Rule
Other Violation
2 violations, Jul 2025 to open · Public Notification Rule
Public Notice Rule and Revised PN Rule
Other Violation2 violations, Jul 2025 to open · Public Notification Rule
Other Violation: 2 violations, open since Jul 2025. A requirement other than monitoring, reporting, or a contaminant limit, such as public notice or the annual water quality report.
Contaminant on the record: Public Notification Rule.
Also violated in the past three years
Jul to Sep 2023 to Jul to Sep 2026
Revised Total Coliform Rule
Monitoring Violation
9 violations, Aug 2023 to Jun 2026
Revised Total Coliform Rule
Monitoring Violation9 violations, Aug 2023 to Jun 2026
Monitoring Violation: 9 violations, Aug 2023 to Jun 2026. The system did not complete required monitoring. This does not show that a contaminant was found.
What the rule requires: The 2013 RTCR (effective 2016) replaced the original TCR. It triggers automatic E. coli testing whenever total coliform is found. A single E. coli-positive sample is an acute MCL violation. It also requires systems exceeding 5% total coliform-positive samples to conduct a formal assessment and correct any deficiencies, helping prevent contamination before it escalates.
About this rule
Interim and Long Term 1 Enhanced Surface Water Treatment Rule
Monitoring and ReportingTreatment Technique Violation
Health-based
27 violations, Jul 2023 to May 2026 · Interim Enhanced Surface Water Treatment Rule
Interim and Long Term 1 Enhanced Surface Water Treatment Rule
Monitoring and ReportingTreatment Technique Violation Health-based27 violations, Jul 2023 to May 2026 · Interim Enhanced Surface Water Treatment Rule
Treatment Technique Violation, health-based: 11 violations, Jul 2023 to Mar 2024. The system did not carry out a required treatment process or corrective action.
Monitoring and Reporting: 16 violations, Aug 2023 to May 2026. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.
Contaminant on the record: Interim Enhanced Surface Water Treatment Rule.
Interim Enhanced Surface Water Treatment Rule, health effects: Violations indicate failure to meet treatment technique requirements that reduce exposure to Cryptosporidium, Giardia, and other microbial pathogens. Cryptosporidium poses the greatest risk to immunocompromised individuals, infants, and the elderly, and can cause severe or fatal illness in vulnerable populations. Limit: Treatment technique — no numeric MCL; compliance means meeting turbidity limits (0.3 NTU in 95% of monthly samples) and Cryptosporidium removal benchmarks
Surface Water Treatment Rule
Monitoring and ReportingTreatment Technique Violation
Health-based
5 violations, Aug 2023 to Jun 2024
Surface Water Treatment Rule
Monitoring and ReportingTreatment Technique Violation Health-based5 violations, Aug 2023 to Jun 2024
Treatment Technique Violation, health-based: 4 violations, Aug 2023 to Nov 2023. The system did not carry out a required treatment process or corrective action.
Monitoring and Reporting: 1 violation, Mar 2024 to Jun 2024. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.
What the rule requires: All systems using surface water (rivers, lakes, reservoirs) or groundwater under surface influence (GWUDI) must filter and disinfect. Treatment technique violations mean the system failed to maintain adequate disinfectant residual, exceeded turbidity limits, or lacked required permits. Snowmelt and storm events can raise turbidity and pathogen loads in surface water.
Health effects: Without proper filtration/disinfection: Giardia lamblia (severe diarrhea, cramping), Cryptosporidium (life-threatening for immunocompromised individuals), viruses (hepatitis A, norovirus). Turbidity itself is not a health risk but can shield pathogens from disinfection. Limit: Treatment technique: turbidity ≤0.3 NTU in 95% of monthly samples; detectable disinfectant residual in 95% of distribution samples
About this rule
Stage 1 Disinfectants and Disinfection Byproducts Rule
Monitoring and Reporting
19 violations, Jul 2023 to Jun 2026 · 2 contaminants
Stage 1 Disinfectants and Disinfection Byproducts Rule
Monitoring and Reporting19 violations, Jul 2023 to Jun 2026 · 2 contaminants
Monitoring and Reporting: 19 violations, Jul 2023 to Jun 2026. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.
Contaminants on the record: Chlorine (MRDL), Carbon, Total.
Lead and Copper Rule Revisions
Reporting ViolationTreatment Technique Violation
Health-based
2 violations, Oct 2024 to Jul 2025
Lead and Copper Rule Revisions
Reporting ViolationTreatment Technique Violation Health-based2 violations, Oct 2024 to Jul 2025
Treatment Technique Violation, health-based: 1 violation, Oct 2024 to Jul 2025. The system did not carry out a required treatment process or corrective action.
Reporting Violation: 1 violation, Oct 2024 to Jul 2025. The system did not report required information on time.
What the rule requires: The 2021 LCRR updated the 1991 LCR with mandatory lead service line inventories and replacement planning, a new 'trigger level' at 10 ppb requiring optimization, and strengthened public education. The 2024 Lead and Copper Rule Improvements (LCRI) further requires replacing all lead service lines within 10 years.
Health effects: Same as Lead and Copper Rule (5000). Violations typically reflect failure to complete the required lead service line inventory or submit a required replacement plan. Lead service lines are the primary source of lead at the tap in many older systems. Limit: Lead action level: 15 ppb (trigger level: 10 ppb); copper action level: 1.3 mg/L
About this ruleLead and copper at the tap
The 90th percentile of the tap samples the system collected in its latest monitoring period, against EPA's action level. Levels vary between homes.
Action level 0.015 mg/L · Jan 2020 to Dec 2022
About this data
Rules violated and the list above come from EPA's SDWIS violation records, one row per violation and contaminant, grouped by the rule each row belongs to. A violation counts when its non-compliance period ended on or after Jul 1, 2023, the start of the thirteen quarters ECHO's three-year figures cover, or is still open; it is unresolved when it was still open at EPA's data refresh on Oct 7, 2026. EPA's rule code 500, "Not Regulated", is left out, as in ECHO's counts. Each rule's violation count is EPA's, and one rule can carry several: a missed monitoring round for a group of contaminants is one violation per contaminant and period. Category names are EPA's violation categories.
ECHO's own summary count of rules violated agrees with this grouping for 98.8% of active systems nationally, and its count of rules being violated for 98.7%; where they differ, the figures here follow the rows listed.
A measured value shown with a rule is the sample result EPA recorded with that violation (SDWIS viol_measure), against the limit EPA recorded on the same row (state_mcl), both in EPA's unit as written; violations without a recorded value, such as missed monitoring, show none. Other measured contaminant levels are not part of this record; each system publishes them in its annual Consumer Confidence Report.
Lead and copper are the newest 90th-percentile results in EPA's SDWA data download (LCR_SAMPLES, codes PB90 and CU90): for each monitoring period a system reports the 90th-percentile value of its tap samples, which EPA compares with its action level of 0.015 mg/L for lead and 1.3 mg/L for copper (40 CFR 141.80). A result is not a measurement of any one tap.
Service area from EPA's Public Water System Service Area Boundaries dataset: State agency. The system's location is the centre of the service area EPA publishes for the system.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Oklahoma records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.