TABLE 1.
Summary of water quality parameter valuesa for normal and red water samples
| Siteb | Temp (°C) | Residual chlorine (mg/liter) | Turbidity (NTUc) | Color (color units) | pH | Total iron (mg/liter) | Dissolved iron (mg/liter) | Sulfate (mg/liter) | Chloride (mg/liter) | Conductivity (μS/cm) | Dissolved oxygen (mg/liter) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| R1 | NDd | ND | 0.56-3.30 | ND | 7.66-8.34 | ND | <0.05 | 23.7-43.6 | 14.2-18.7 | ND | ND |
| R2 | ND | ND | ND | ND | ND | ND | ND | 200-230 | 41.0-44.7 | ND | ND |
| Z | 20-22 | 0.03-0.08 | 1.60-27.5 | <5-35 | 7.59-7.69 | 0.39-1.39 | <0.05-0.17 | 63.0-68.3 | 23.4-24.7 | 393-472 | 6.73-7.41 |
| J | 20-22 | 0.03-0.05 | 0.45-31.9 | <5-28 | 7.56-7.60 | 0.12-1.61 | <0.05-0.07 | 58.8-64.2 | 23.2-23.6 | 403-463 | 7.02-7.50 |
| S | 20-22 | 0.03-0.2 | 0.98-12.3 | <5-12 | 7.59-7.73 | 0.15-0.67 | <0.05-0.15 | 59.1-70.7 | 23.4-26.0 | 440-487 | 7.02-7.48 |
| D | 20-22 | 0.1-0.6 | 0.09-0.63 | <5 | 7.50-7.84 | <0.05-0.07 | <0.05 | 54.1-89.0 | 22.0-25.5 | 390-470 | 8.01-8.62 |
| Inlet | 17-20 | 0.7-0.8 | 0.09-0.12 | <5 | 7.68-7.74 | <0.05 | <0.05 | 57.8-95.7 | 24.3-30.4 | 400-460 | 8.14-8.55 |
a
The ranges of values are shown.
b
R1 represents raw water before the switch to a new source of water; R2 represents the new source of water. The four sampling points (Z, J, S, and D) represent endpoints of the drinking water distribution system located in different downtown areas; samples were taken during the red water event. Inlet represents inlet water of the drinking water distribution system during the red water event.
c
NTU, nephelometric turbidity units.
d
ND, not determined.