Water Quality Indices (WQI) - Water Quality Management: Assessment and Interpretation - page 33

Fig. 3.4 Location of the Se d-Rud River

flow of 2,000 m 3 /s and the minimum of 4 m 3 /s.
Another branch is Shahrud that is originated from the mountains of Alamot and
Talaghan with the maximum

and Azarbaijan with the maximum

flow of 6 m 3 /s
(Figs. 3.5 and 3.6 ). The dam constructed on the river is located at 200 km to
northwest of Tehran and 100 km to Caspian sea at the con

flow of 800 m 3 /s and the minimum

uence of two rivers of

is area is 57,880 km 2 and length of this river is
670 km; the basin is located in orbit of 49.9422

Ghezelozan and Shahrod. Basin '

° °

eastern and 37.4692 northern.

Water samples collected from upstream and downstream of the Se d-Rud dam

'

which it is location is illustrate in Fig. 3.5 for upstream and Fig. 3.6 for downstream.

The aim of this case study was to indicate the application of NSWQI methods for
general water quality index and using BCWQI techniques for drinking purposes
and agriculture in Se d-Rud River.

The mean of the water quality data of the 21 stations which was monitored by
Water Research Institute (Iran) between 2005 and 2006 is presented in Table 3.7 .In
this part, the numerical value of the NSFWQI method calculated for each of the 21
qualitative monitoring stations which is shown in Figs. 3.5 and 3.6 . Equation 3.1 used
to calculate the NSWQI. Due to lack of reliable data for fecal coli form and turbidity
for all the stations, other parameters include DO, BOD 5 ,PO 4 ,NO 3 , pH, TS and
temperature were used to compute the WQI. Figure 3.7 indicates the results. As
indicated in Fig. 3.7 , according to the NSFWQI method the GSW5 station with the
47.41 had poor water quality and other stations were in the mediumwater quality. The
ST2.1 station with 66.9 was in medium quality and had better condition than others.