L. Srinivas et al. International Journal of Recent Research Aspects ISSN: 2349-7688, Vol. 4, Issue 4, Dec 2017, pp. 6-10 © 2017 IJRRA All Rights Reserved page-6- Assessment of Water Quality Index in Lower Manair Dam, Karimnagar district, Telangana L. Srinivas 1 , Y.Seeta 2 , P. Manikya Reddy 3 1 Assistant Professor, Sri Chaitanya Degree and PG College, Karimnagar. 2 Research Scholar, Department of Environmental Science, Osmania University, Hyderabad. 3 Professor, Department of Botany, Osmania University, Hyderabad, Telangana. Abstract: In the present study, water quality of surface water has been assessed in terms of water quality index (WQI) in Manair dam, Karimnagar district of Telangana. Ten parameters have been selected; they are pH, total alkalinity, chlorides, total hardness, calcium, magnesium, nitrates, sulphates, total dissolved solids and dissolved oxygen. Three sampling stations were selected for the collection of water samples. The samples were analyzed on the same day in the laboratory for different physico-chemical parameters following the standard methods (1). Based on the results obtained, all the physico-chemical parameters are well below the permissible limits as prescribed by Indian standards. The WQI show that overall stations in Manair dam in Karimnagar district, qualify in the ‘Good’ category and it is fit as such for domestic and irrigation purpose. Keywords: Water Quality Index, Surface Water and Manair Dam. I. INTRODUCTION WQI indicates the quality of water in terms of index number which represents overall quality of water for any intended use. It is defined as a rating reflecting the composite influence of different water quality parameters were taken into consideration for the calculation of water quality index (WQI) .The indices are among the most effective ways to communicate the information on water quality trends to the general public or to the policy makers and in water quality management. In formulation of water quality index the relative importance of various parameters depends on intended use of water. Mostly it is done from the point of view of its suitability for human consumption. Water quality index (WQI) provides information about water quality in a single value. WQI is commonly used for the detection and evaluation of water pollution and may be defined as a reflection of composite influence of different quality parameters on the overall quality of water (6). WQI indices are broadly classified in two types; they are physico-chemical and biological indices. The physico-chemical indices are based on the values of various physico-chemical parameters in a water sample, while biological indices are derived from the biological information (9). Here prompt and reliable attempt has been made to calculate the water quality index of the study area based on physico-chemical data (10, 14, 11,7, 13 and 8). II. STUDY AREA Lower Manair Dam Situated at Karimnagar District. Lower Manair Dam Works will start in1974 and ending in 1985. In Manair Dam area at kakatiya Canal 146.00 km to 234 km. Lower Manair Dam Water will goes up to 2,62,326 ac s. The Dam is constructed across the Manair River at 18°24' N latitude and 79° 20' E longitude in Karimnagar District at Km.146 of Kakatiya Canal. Lower Manair Dam is a balancing reservoir built across the river Manair a tributary of Godavari at Karimnagar. It is having a storage capacity of 24 TMC. The water is used for drinking, agriculture and supports fish culture. III. MATERIAL AND METHODS Three sampling stations were selected for the collection of water samples. Station-I is situated right side of the lake. The water samples from the surface were collected at all the sampling stations in 2L polythene containers at monthly intervals for a period of 2 years from June 2013 to August 2015.The samples were analyzed on the same day in the laboratory for different physico-chemical parameters following the standard methods (1). Water quality index provide information on a rating scale from zero to hundred. Higher value of water WQI indicates poor quality of water and lower value shows good water quality. The computed WQI values are classified into six types; “excellent water” to “water unsuitable for drinking” is given Table: 6 (2). The water quality parameters are selected based on its direct involvement in deteriorating of surface water quality for human consumption. Calculation: During the present study, the standards for the drinking water, recommended by BIS are considered for the computation of surface water quality rating (qi) and unit weights (Wi), for the purpose of calculate WQI. Ten parameters have been selected; they are pH, total alkalinity, chlorides, total hardness, calcium, magnesium, nitrates, sulphates, total dissolved solids and dissolved oxygen. The standard values of surface water quality parameters, their corresponding ideal values and unit weights are given in table: 1. For computing WQI three steps involved. In the first step, each of the all parameters has been assigned a weight (wi) according to its relative importance in the overall quality of