Escherichia coli as a Tool for Disease Risk Assessment of Drinking Water Sources

Table 1

The range of seasonal E. coli counts (MPN/100 ml) in water.

Water sources	Seasonal counts (MPN/100 ml)
	Dry season	Wet season
Borehole	0–0.2 × 10^1	0–0.2 × 10^1
Canal	2.3 × 10^1–1.1 × 10^2	3.1 × 10^1–6.3 × 10^1
Dam	0.7 × 10^1–1.1 × 10^2	1.2 × 10^1–7.9 × 10^1
Hand-dug well	0–0.2 × 10^1	0–0.4 × 10^1
River	0–0.1 × 10^1	0.2 × 10^1–0.7 × 10^1
Streams	0–3.3 × 10^1	0–3.3 × 10^1