Table 2. P-values for Wilcoxon-Mann-Whitney tests (unpaired data) and Wilcoxon signed-ranks tests (paired data) comparing log concentrations of fecal indicator bacteria (FIB) in samples (first row) and hypothesis tests comparing proportions of positive samples (second row) (McNemar’s chi square test for paired data, and Fisher’s exact for unpaired data) for samples collected at different points in the supply chain.

	Finished PSW (PWMF)		Finished PSW (POS)		Exterior PSW		HH Water for Consumption
	E. coli	TC	E. coli	TC	E. coli	TC	E. coli	TC
Raw water	0.0037**	0.0006**	0.1231	0.9688	---	---	0.8845	0.0000**
	0.0009**	0.0001**	0.388	1.000	---	---	1.00	0.000**
PSW PWMF	---	---	0.0723	0.0008**	---	---	0.0009**	0.0000**
			0.160	0.31*	---	---	0.002**	0.000**
PSW POS	---	---	---	---	0.5148	0.1190	0.0757	0.0000**
	---	---	---	---	0.212	0.127	0.323	0.000**
Exterior PSW	---	---	---	---	---	---	---	---
	---	---	---	---	---	---	---	---

*indicates statistically significant difference at 95%.

**indicates statistically significant difference at 99%.