Parameter
Unit
Shallow groundwater
River water
WHO 2004
Ave
Min
Max
SD
Ave
Min
Max
SD
pH
6.3
6.0
7.0
0.3
6.8
6.5
7.0
0.2
6.5 - 8.5
EC
µS/cm
360
225
540
132.7
193.3
123
293
74.0
1500
Salinity
mg/L
179
114
270
66
96.0
61
141
35.6
-
DO
mg/L
2.3
1.5
4.7
1.1
4.3
2.5
6.3
1.7
-
-N
mg/L
1.5
0.6
2
0.5
2.3
0.8
4.3
1.5
1.5 as NH3
NO3-N
mg/L
0.5
0.1
1.4
0.4
0.4
0.2
0.5
0.1
50.0 for total nitrogen
COD
mg/L
5.0
4.5
6.0
0.6
8.0
6.5
9.4
1.3
PO4
mg/L
1.0
0.6
2.5
0.7
0.5
0.3
0.7
0.2
0.4 - 5.5
Fe
mg/L
1.3
0.3
2.5
0.8
0.3
0.2
0.4
0.1
0.3
Cl−
mg/L
14.3
4.0
21
5.7
10.6
6.3
17.4
5.0
250
Na+
mg/L
18
15.7
20.3
2.0
14.6
10.6
20.0
4.3
-