HYDROCHEMICAL STUDIES IN UPPER HINDON BASIN, DISTT. SAHARANPUR, U.P., INDIA

Abstract

There is an increasing awareness for the maintenance of water quality especially in urban areas, while attempting to locate new and sizeable sources of water. The quality of natural waters has been affected by man through various activities like channelization, deforestation, industrialization, urbanization as well as agriculture. The present work was taken up with the aim of studying the chemical characteristics of surface and ground waters of the upper part of Hindon river basin (latitude 29°55' and 30°0' N; longitude 77 30' and 77°40'E) with the following objectives: - To evaluate the chemical characteristics of surface water of the Hindon river system and of ground water in the basin by using appropriate methods of representing water quality data with the view of assessing the synoptic quality for various specified uses. This also includes the study of the temporal variations in chemical characters of natural waters. - To identify the major point sources of pollutants and to study their salient quality characteristics. - To ascertain the impact of biodegradable organics on water quality and the associated DO-BOD relationship. - To study the adsorption of selected toxic metals on the sediments of the area. - V The area of study is a part of Indogangetic plain and is located in Saharanpur district, Uttar Pradesh, India. The Hindon river is the main stream which is fed by several rivulets (popularly known as nalas) viz. Nagdeo nala & Dhamola nala. The Hindon river is of perennial nature, only in parts, downstream of its confluence with the Nagdeo nala. It meets the river Yamuna near Okhla in Delhi. In the vicinity of Saharanpur town, various industries have come up such as those related to the cardboard, paper, dairy products, rubber, steel rolling, electroplating etc. which release effluents into the riverine system. The main effluent discharges are from the Star Paper Mill and the Foremost Dairies which are reported to be about 37,950 KLPD and 2000 KLPD respectively. The chemical analyses of waste effluents of Star Paper Mill and Foremost Dairies show that these wastes are rich in organic substances as reflected by high BOD and COD. In the course of field monitoring, fourteen sets of surface water and ground water samples were collected from various locations during April,1985 to November,1987. The chemical data of ground water and surface water have been represented on maps by the Stiffs diagram. The Piper Trilinear diagrams for ground water indicate the dominance of excessive noncarbonate hardness or the carbonate hardness. In ground water and surface water selected trace metals (like Cd , Pb and total chromium) show high concentration (0.19 - VI - mg/1, 1.96 mg/1 and 0.32 mg/1 respectively) and thus render the water unfit for drinking purposes at various locations. An attempt has been made to work out water quality indices for surface water of the area using Horton based procedures. A rating scale has been defined in the range of 100 to 400. The weights were assigned to various water quality parameters in the range of 1 to 5 according to their relative importance; a rating value for each parameter was computed from developed equations. Using the rating value and weight factor for the respective parameters,water quality indices were obtained by taking weighted arithmetic mean. An ambient water quality index, modified after Inhaber (1975) has also been calculated, for trace metals using subindices for toxic metals, DO,BOD and ammonical nitrogen. The data indicate that the ambient water quality index is in the range of 1.075 to 115.360. The water quality index profiles along the Hindon-Nagdeo streams indicate that the quality of surface water deteriorates considerably downstream of the outfall of the Dairy waste and Paper Mill waste. In the intermediate stretches, the water quality shows a steady improvement due to reoxygenation. Also, the quality of surface water improves considerably downstream of the confluence of the Dhamola nala with the Hindon river indicating an overall better quality of water in Dhamola nala. Generally, in summer months (May, 1985 and May, 1986) water quality index of surface water is relatively higher than the monsoon months VII - (August, 1985 and August, 1986) indicating the dilution effects due to rainfall. The ambient water quality index profiles along the Hindon river and its tributaries are generally similar in nature as the quality profiles based on Horton indices. The dissolved oxygen sag curves were computed for the surface waters for four periods between September,1986 - October,1986 and November,1987 using DOSAG-I water quality routing model given by the Texas Water Development Board, USA. The computation of BOD and DO involved evaluation of reaeration constant (K ) from a discretized form of Streeter - Phelps (1925) equation. The values of deoxygenation coefficient (kJ) were calculated from the equation based on the Streeter - Phelps equation and the approach based on Bhargava (1986) which takes into consideration the phenomenon of bioflocculation and sedimentation. The DO sag curves developed by using k'2 values calculated from Streeter - Phelps based equations show a noticeabledisagreement between observed and computed DO curves at some places. In the approach suggested by Bhargava (1986), the computed and observed DO curves exhibit fairly close agreement at most of the locations. The Root Mean Square error between observed and computed DO values in the first approach is also somewhat higher than calculated for DO sag curves computed by the Bhargava's approach. The DO sag curves for Dhamola stream show higher DO levels as compared to Hindon - Nagdeo stretches indicating thereby better - VIII organic quality of the Dhamola waters. This fact is also corroborated by the continuing rise in dissolved oxygen downstream of confluence of Dhamola with the Hindon river. An attempt has also been made to study the distribution of heavy metals (viz. lead, zinc and manganese) in the river bed sediments for determining the sorption behaviour of freshly deposited sediments. The sediment samples were collected close to the waste outfall locations. A background sample was also collected from the nearby place for comparision purposes. Batch studies were performed for the determination of optimum pH and sediment dose for the adsorption of metal ions. Adsorption experiments with varying adsorbate concentration were run to study the behaviour of isotherm by applying Langmuir and Freundlich models. The various parameters, for the three metal ions as obtained from Langmuir and Freundlich models, do not show any particular gradation. The maximum adsorption values obtained in the laboratory are quite different from those calculated on the basis of above models. These models do not hold true for the entire concentration range of the adsorbates studied, which may be a reason for the above mentioned disparity. The analytical data of two metal ions (Pb++ and 2n++) in water and sediment show good correlation,both being in relatively high concentrations. It appears that metal content of the aqueous discharge is taken up by the sediment and presently the chances of the reverse IX - process seem to be remote. In terms of pollution, the risk from the discharged water is much less in comparison to the sediments which in course of time may start transporting the toxic metals to nearby areas. The present study has brought out the quality characteristics of the surface water and ground water in the upper Hindon basin in terms of the conservative and degradable constituents. The spatial and temporal variations in water quality due to waste outfalls from dairy and paper industries on the stream water have also been highlighted.