Enid water report flags lead-service inventory violation despite 2025 compliance

Enid water report flags lead-service inventory violation despite 2025 complianceEnid's 2026 Consumer Confidence Report says the city met the drinking-water standards shown in the report for calendar year 2025. But the disclosure also records a Lead and Copper Rule Revisions violation concerning the initial lead service line inventory, as the utility continues to identify service-line materials across the community.

Enid reported that 124 groundwater wells supplied its water system during 2025.

The report records a Lead and Copper Rule Revisions violation for “LSL Inventory-Initial” covering October 17, 2024 to March 20, 2025.

The city said its overall lead result was below the federal action level and that it continues to compile a community-wide service-line inventory.

Nitrate-nitrite reached 8.66 mg/l against a 10 mg/l maximum contaminant level; combined radium reached 4.91 pCi/L against a 5 pCi/L limit.

Enid's latest Consumer Confidence Report places continued service-line identification alongside compliance monitoring as the key infrastructure issue for its groundwater-based drinking-water system. The 2026 report, covering calendar year 2025, states that Enid's drinking water met the state and federal standards shown in the report. The system was supplied by 124 groundwater wells and is subject to routine monitoring for regulated contaminants, disinfection byproducts, lead and copper, radiological contaminants and selected unregulated contaminants. However, the report also discloses a drinking-water regulation violation under the Lead and Copper Rule Revisions. The listed compliance period ran from October 17, 2024 to March 20, 2025, and the report identifies the issue as “LSL Inventory-Initial.” No further detail on the violation was provided in the meeting material. City materials say Enid is continuing work on its service-line inventory to identify pipe materials throughout the community. The report directs customers seeking access to the inventory to contact Enid Water Production. Enid's overall lead result was reported below the federal action level. The report gives a 90th-percentile lead result of 5.1 ppb for the 2022-24 monitoring period, compared with a 15 ppb action level, while listing two sites over the action level. It notes that lead is generally associated with service lines and plumbing in or leading to individual homes, rather than the water source itself. Several groundwater-quality parameters were below, but relatively close to, their federal limits. Nitrate-nitrite recorded a highest value of 8.66 mg/l, against a 10 mg/l maximum contaminant level. Combined radium-226 and radium-228 reached 4.91 pCi/L, just below the 5 pCi/L limit. Arsenic reached 5.5 ppb, below its 10 ppb limit. The system is required to collect at least 50 microbiological samples each month under the Total Coliform Rule. The city said routine monitoring continues throughout the year, rather than being confined to the annual report.