Affiliations: Department of Chemistry, S.C.S. (Autonomous) College,
Puri - 752 001, Orissa, India | Regional Research Laboratory, Bhubaneswar - 751013,
Orissa, India | Department of Chemistry, Utkal University, Bhubaneswar
- 751004, Orissa, India
Abstract: Water Quality Index (WQI) plays an important role in interpreting
the information on water quality trends of a water body and was used to denote
degradation of river water quality. WQI technique was applied for the
classification of Mahanadi river-estuarine waters with respect to three major
use purposes. WQI representing importance of the variables was studied with
respect to suitability of river water for drinking, aquatic lives and
irrigation purposes for 31 different stations of the river during six different
seasons (pre-monsoon, monsoon and post monsoon during 2001–02 and
2002–03). In the formulation of a WQI, the importance of various
parameters (pH, EC (electrical conductance), DO (dissolved oxygen), BOD
(biochemical oxygen demand), TDS (total dissolved solids), turbidity, SO4,
chloride, nitrate, sodium, calcium, magnesium, alkalinity and hardness) depends
on the intend use of water. The results of different WQI produce similar trend
but different index values as well as some different remarks. The present study
reveals that the water quality of Atherbanki creek irrespective of seasons, is
quite unsuitable for all the three purposes, which may be due to the combined
impact of municipal effluent from Paradip township, industrial effluents from
industries like PPL** and also saline influence. The application of a WQI to
the Mahanadi river allows a water quality classification both spatial and
temporally, that is reproducible within the river by means of uniform,
objective criteria. Such an approach permits the identification of stretches of
river that may require urgent measures in order to restore minimal water
quality uses for different purposes, and can be applied beyond the Mahanadi river. From the present observation, it can be concluded that three major
townships (Sambalpur, Cuttack and Paradip) in the basin produce negative impact
on the Mahanadi river water quality, particularly serious after the city sewage
discharge. Effective pollution control measures must be taken in the near future.
Keywords: WQI, drinking, irrigation, aquatic lives, Mahanadi river, India
