| Indicator organism | UHWW (n = 20) | THWW (n = 20) |
| Total heterotrophic count (CFU/mL) | 1.9 × 108 | 1.6 × 106 |
| Total coliform count (CFU/100mL) | 2.6 × 1010 | 2.2 × 106 |
| Fecal coliform count (CFU/100mL) | 1.25 × 109 | 2.0 × 105 |
| E. coli count (CFU/100mL) | 4.5 × 105 | 1.1 × 104 |