Effects of Opened and Closed Spillway Operations of a Large Tropical Hydroelectric Dam on the Water Quality of the Downstream River

Table 4

Classification of water quality parameters for all stations during opened and closed spillways according to NWQS [14].

Station

Opened spillway

Closed spillway

pH

DO

Turbidity

TSS

COD

NH3-N

NO2-N

NO3-N

pH

DO

Turbidity

TSS

COD

NH3-N

NO2-N

NO3-N

1

II

I

II

II

V

III

I

I

III

III

>II

II

IV

I

I

I

2

II

I

>II

I

V

II

I

I

III

III

II

II

IV

II

I

I

3

II

I

>II

I

V

II

I

I

III

III

>II

II

V

II

I

I

4

II

I

>II

II

V

II

I

I

II

III

>II

II

V

II

I

I

5

II

I

>II

II

V

III

I

I

II

III

>II

III

V

III

I

I

6

II

I

>II

III

V

II

I

I

III

III

>II

II

IV

III

I

I

7

II

I

>II

II

V

II

I

I

II

III

>II

III

IV

II

I

I

8

II

I

>II

III

V

II

I

I

II

III

>II

III

IV

II

I

I

9

II

I

>II

II

V

II

I

I

II

III

>II

III

IV

II

I

I

10

II

I

>II

II

IV

II

I

I

II

III

>II

II

IV

II

I

I

11

II

I

>II

II

IV

II

I

I

II

III

>II

III

V

II

I

I

12

II

I

>II

III

IV

II

I

I

II

III

>II

III

V

II

I

I

13

II

I

>II

II

IV

II

I

I

II

II

>II

III

V

II

I

I

14

II

I

>II

III

V

II

I

I

II

II

>II

III

IV

II

I

I

15

II

I

>II

III

V

III

I

I

II

II

>II

III

V

III

I

I