Spatial-Temporal Dynamics in Potable Water Quality: A Case Study of Mizan-Aman Town, Southwest, Ethiopia

Table 1

Seasonal variation in water physicochemical and bacteriological characteristics.

Seasons

T (°C)

TU (NTU)

EC (µS/cm)

TSS (mg/l)

pH

TH (mg/l)

TDS (mg/l)

BOD (mg/l)

PO4(mg/l)

NO3(mg/l)

NH4(mg/l)

TC (cfu/100 ml)

FC (cfu/100 ml)

Dry

27.1 ± 1.4a

37.4 ± 12b

42.6±3b

190.8 ± 52b

7.6 ± 0.4b

27.8±7b

83.5 ± 24b

18.1 ± 1.8b

2.4 ± 1.0b

3.5 ± 0.5b

2.2 ± 0.6b

366.5 ± 97b

209.5 ± 21b

Wet

23.8 ± 1.0b

54.8 ± 14a

55.0 ± 12a

260.5 ± 42a

8.1 ± 0.4a

35.8±6a

131.4 ± 36a

20.7 ± 2.2a

3.5 ± 1.5a

7.0 ± 1.7a

4.8 ± 1.8a

494.3 ± 114a

278.3 ± 61a

Overall mean ± SD

25.4 ± 2.0

46.1 ± 16

48.8 ± 10

225 ± 59

7.9 ± 0.5

31.8 ± 8

107.4 ± 39

19.4 ± 2.3

2.9 ± 1.4

5.2 ± 2.1

3.5 ± 1.9

430.4 ± 123

243.9 ± 62

ES

—

7

1500

—

6.5–8.5

300

1000

10

0.02

50

1.5

0

0

The WHO

<15

5

1500

<300

6.5–8.5

300

1000

5

0.01

50

1.5

0

0

TU: turbidity unit, NTU: nephelometric turbidity unit, TSS: total suspended solid, EC: electrical conductivity, TH CaCO₃: total hardness, T°: temperature, TDSs: total dissolved solids, RC: residual chlorine, ND: not detected, BOD: biological oxygen demand, TC: total coliform, and FC: fecal coliform. The analytical results were statistically significant at . Means in columns followed by the same letter(s) are not significantly different at 5% level of significance. Water standard: ES: Ethiopian standard for drinking water quality and the WHO: the World Health Organization.