Escherichia coli
Cities measured
87
Detected in
2 / 87
Elevated / alert
2
Highest
12 CFU/100mL — Beirut
Overview
E. coli is the primary indicator of recent faecal contamination in drinking water. The EU Drinking Water Directive requires zero E. coli per 100 mL of treated water — any detection constitutes an exceedance and requires immediate investigation.
Health Relevance
Most E. coli strains are harmless. Pathogenic strains like STEC O157:H7 cause severe haemolytic uraemic syndrome (HUS) — kidney failure, particularly in children. The 2011 E. coli O104:H4 outbreak in Germany killed 54 and affected 3,800, linked to contaminated fenugreek sprouts irrigated with contaminated water.
Regulatory Limits
Drinking Water Directive 2020/2184
0 per 100 mL.
Controversy & Contested Science
Private water supplies (wells, springs) serving ~10–15% of EU rural populations are poorly regulated and frequently E. coli-positive. The 2000 Walkerton, Ontario E. coli outbreak — killing 7, sickening 2,300 — resulted from a water operator's failure to report chlorination lapses amid systemic underfunding of small-system oversight. The EU Drinking Water Directive has not fully addressed regulatory gaps for private wells and small community supplies, where E. coli monitoring may occur only annually or less.