Assessment of water quality in Hindon river basin

Abstract

An extensive field survey in Hindon river basin was carried out and three wastewater samples from Nagdev Nala, Star Mill Drain and Dhamola Nala, water samples from river Kali and Krishni, eleven water samples from different stretches of river Hindon and sixty eight groundwater samples from hand pumps of different locations in the Hindon river basin were collected in pre- and post-monsoon seasons during 2012 and analysed for physicochemical and bacteriological parameters, metal concentrations and organochlorine pesticides. Maximum value of BOD (261 mg/L) was observed in Star Paper Mill Drain. The higher values of BOD and COD observed in the drains and river Hindon indicate high degree of organic pollution rendering the water unsuitable even for bathing purpose. At almost all sites of the upstream and mid-section of the river Hindon, DO was observed to be nil because of high organic load in the river water. The values of re-aeration coefficients and deoxygenation coefficients for different stretches of river Hindon were computed and the results of estimated BOD at different sampling sites are well in agreement with observed values. The DO Sag analysis (using Streeter & Phelps, 1925 and differential equations of DO Sag) can be successfully used to predict the DO level at different location of the river. Ground water quality data has been processed as per BIS and WHO standards to examine the suitability of water for drinking purpose. Degraded water quality zones have been identified based on water quality parameters not conforming the drinking water standards. Water quality standards have been violated for TDS, hardness, alkalinity, Ca and Mg at few locations. Nitrate concentration in few of the ground water samples exceeded the maximum permissible limit of 45 mg/L, which may be attributed to contamination by domestic waste disposal. Bacteriological contamination was observed in few ground water samples in the vicinity of river Hindon, which may be attributed to unorganized sewerage system in the study area. The concentrations of Fe, Mn, Ni, Cr, Pb and Cd in few ground water samples exceeded the permissible limit prescribed for drinking purpose, which may be attributed to the leaching of effluent containing wastes from different industries operating in the basin. The concentration of α-BHC, γ-BHC and Methoxychlor were detected in few ground water samples of the study area, which may be attributed to extensive use of these pesticides in agricultural practice in the study area, which might have leached to ground water system. Almost all collected groundwater samples from Hindon river basin falls in rock dominance zone suggesting evolution of water chemistry influenced by water-rock interaction. The scatter plot of (Ca+Mg) vs TZ+ and high (Ca+Mg)/(Na+K) ratio indicate that carbonate weathering is a major source of dissolved ions in the groundwater of the study area. Assessment of suitability of the groundwater of the study area for irrigation purpose on the basis of total soluble salts, SAR, RSC and heavy metals revealed that these waters are of medium to good quality for irrigation purpose. The chemical data of ground water samples of the study area has been processed using per Piper trilinear diagram, Chadha’s diagrams and Durov’s diagram for classification and majority of the ground water samples of the study area belong to Ca-Mg-HCO3 hydrochemical facies in both pre- and post-monsoon seasons. Water type C3-S1 as per U. S. Salinity Laboratory Classification and fall under normal to low saline type on the basis of salinity, non-sodic water as per sodicity and non-alkaline water as per alkalinity classification as per Gupta’s classification were observed. The water quality of river Hindon at all sites in both season was found to be bad and most of the ground waters were found in the good to excellent category type on the basis of Water Quality Index. Possible remedial measures have also been discussed and recommendations for preventing the deterioration of ground water quality have been suggested.