TABLE 5: Results of univariate linear regression models testing the effect of factors associated with log reductions in E. coli concentrations between the source and the point of use after 24 (±3) hours of storage. Results are presented collectively and stratified by chlorine treatment group. MPN = Most Probable Number; NTU = Nephelometric Turbidity Units.

	Coeff	Lower 95% C.I.	Upper 95% C.I.	p-value
Baseline E. coli (unit increase of 10 MPN/100mL)
Overall (n=68)	0.011	0.005	0.018	0.001 *
Local Chlorine (n=39)	0.0160	0.007	0.025	0.001 *
Commercial Chlorine (n=29)	0.007	−0.003	0.017	0.145
Turbidity (unit increase of 1NTU)
Overall (n=67)	0.006	−0.009	0.213	0.424
Local Chlorine (n=39)	0.010	−0.010	0.031	0.319
Commercial Chlorine (n=28)	0.002	−0.024	0.028	0.872