Yellowstone Valley Inn
Transient non-community system in Cody, Park County, Wyoming, serving 237 people from ground water. 1 rule violated in the past three years. Privately owned.
Quarterly compliance history
2023
2024
2024
2024
2024
2025
2025
2025
2025
2026
2026
2026
2026
Rules violated in the past three years
Oct to Dec 2023 to Oct to Dec 2026
Nitrite
Nitrite (NO₂) enters water from fertilizer runoff, septic systems, and natural mineral deposits.
Nitrite
Nitrite (NO₂) enters water from fertilizer runoff, septic systems, and natural mineral deposits.
What it means: Nitrite (NO₂) enters water from fertilizer runoff, septic systems, and natural mineral deposits. Unlike nitrate, nitrite acts very quickly in the body — it converts hemoglobin to methemoglobin, which cannot carry oxygen. Nitrite can also form in distribution systems through microbial nitrification when chloramine disinfection breaks down.
Health effects: Methemoglobinemia ('blue baby syndrome') in infants under 6 months: reduced oxygen delivery to tissues can be life-threatening. Pregnant women and people with glucose-6-phosphate dehydrogenase (G6PD) deficiency are also at elevated risk. Adults are generally less susceptible due to more effective methemoglobin reduction.
Limit: 1 mg/L as nitrogen (NO₂-N)
About this contaminantAbout this data
EPA counts the rules a system was in violation of, not the individual violations; one rule can carry several in the same period. Unresolved means still in violation at EPA's latest data refresh. Measured contaminant levels are not part of this record; each system publishes them in its annual Consumer Confidence Report.
Service area from EPA's Public Water System Service Area Boundaries dataset: location confidence LOWER. 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 Wyoming 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. Retrieved from ECHO on Oct 11, 2026.