Table 5.

ANOSIM analysis of microbial community structures in different sample groups^a

Factor	Water sample or system or pairwise test comparison	Global R value	P value
Site	BCV, PCF (postflushing samples)	0.298	0.001
Water age (days)	3 to 6, 6 to 8, 8 to 10, 10 to 12, ≥17	0.097	0.003
	3 to 6, 6 to 8	0.147	0.041
	6 to 8, 8 to 10	0.095	0.028
	8 to 10, 10 to 12	0.118	0.01
	10 to 12, ≥17	0.078	0.148
	3 to 6, 8 to10	0.103	0.054
	3 to 6, 10 to 12	0.222	0.002
	6 to 8, 10 to 12	0.06	0.09
	3 to 6, ≥17	0.12	0.057
	6 to 8, ≥17	0.069	0.205
	8 to 10, ≥ 17	−0.031	0.603
Sample type	Water sample, biofilm sample	−0.016	0.636
	First draw sample, flushing sample, water heater sample	0.009	0.297

^aPaired date ranges represent pairwise tests. Bold values indicate significant difference with 95% confidence (P < 0.05).