Table 1.

Chi-squared analysis of E. coli (CFU/100 mL) vs. ER cut-off values from the freshwater samples presented in Figure 1. Χ² = 47.57, Degrees of freedom = 4, p-value = 0.0001.

	E. coli CFU/100 mL of Water
	0–10 (Low Risk)	11–100 (Intermediate Risk)	>100 (High Risk)	Total
<500 ER	9	0	0	9
500–7000 ER	12	9	3	24
>7000 ER	2	5	29	36
Total	23	14	32	69