Ski Apache

What it means: E. coli is a fecal indicator bacterium. Its presence in treated water is an acute health violation, meaning the system must notify customers within 24 hours. Detection requires immediate corrective action — typically a boil water advisory, investigation of contamination source, and system flushing.

Health effects: Most E. coli strains cause diarrheal illness. Some strains (e.g., O157:H7) produce toxins causing severe bloody diarrhea, hemolytic uremic syndrome (HUS — a form of kidney failure), and death — especially in children under 5 and the elderly. Even non-pathogenic strains in drinking water indicate that disease-causing organisms may also be present.

Limit: Zero (one confirmed positive sample = acute MCL violation)

What it means: The 2006 GWR requires regular sanitary surveys of groundwater systems and targeted corrective action when fecal indicators are found in source water. Systems with significant deficiencies must provide 4-log virus treatment (99.99% removal/inactivation) or fix the deficiency.

Health effects: Protects against enteric viruses, which can contaminate groundwater via cracked well casings, failing septic systems, or animal waste. Viruses persist longer in groundwater than in surface water. Hepatitis A and norovirus are the primary pathogens of concern.

Limit: Treatment technique: 4-log virus treatment required when source water has fecal indicators or significant sanitary deficiencies

What it means: When a system violates a drinking water standard, it must notify customers promptly: within 24 hours for acute violations (e.g., E. coli), 30 days for non-acute MCL violations, and 1 year for monitoring failures. A violation means the notification was late or missing — not that the underlying water issue is necessarily severe.

Health effects: No direct health risk from the notification violation itself, but delayed notification means customers may have consumed contaminated water without the chance to take protective action (boil water orders, bottled water use).

Limit: No MCL — compliance requires meeting specific notification deadlines

What it means: 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.

Health effects: Total coliform bacteria indicate that the disinfection barrier has been breached or fecal contamination is entering the system. E. coli specifically indicates fecal contamination and the possible presence of disease-causing pathogens (norovirus, Salmonella, Shigella, Campylobacter). Illness can be severe in elderly, young children, and immunocompromised individuals.

Limit: Zero E. coli; ≤5% of monthly samples total coliform-positive