[en] Inland salinity of groundwater in parts of Purna alluvial tract is a very interesting phenomenon because it lies 800 km away from seacoast and no remnants of irrigation practices have been observed. Out of the total area of about 7500 km², the salinity affected area is about 2956 km², which is confined mainly in the northern and central parts of the Purna alluvium in Amravati, Akola and Buldhana districts of Maharashtra. The thickness of saline aquifer varies from 50 m to 420 m deepest in the basin. Different types of land forms, viz. older flood plain, piedmont zone, alluvial fans, pediplain with alluvial cover, interfans, dissected alluvial platform are identified within the alluvial plain: Rock types exposed in the area are Upper Gondwana, Infra trappean bed, Deccan trap and Quaternary sediments. Quaternary sediments cover much of the area while basin margins are mainly of Deccan Trap. The Groundwater Surveys and Development Agency (GSDA) of Maharashtra State carried out a 'Induced Recharge Project', whereby the river water of good quality was intended to be used for recharging the groundwater in the aquifers adjoining the river courses. A large number of wells were drilled along the river banks and operated to create a reverse groundwater level gradient. In the present paper presents the results of the work that was carried out to understand the causes of groundwater salinity in parts of the Purna river basin using chemical and isotopic approaches. Also the evaluation of the performance of the wells drilled and being operated under an ongoing induced recharge project of the GSDA is presented. A detailed study of available information on the hydrogeology, hydrochemistry, soil characteristics, hydrometeorology, land use pattern, and hydrology was carried out prior to the collection of river and groundwater samples from 37 locations in the study area. The samples were subjected to hydrochemical analyses for major ions such as Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃^-, SO₄^2-, and Cl^-, trace elements such as Sr and Li, environmental tritium, carbon-14, and stable isotopes of oxygen and hydrogen (¹⁸O and D). The hydrogeological and hydrometeorological data reveal that the thick clayey soil strata, low annual rainfall and very low transmissivity and specific yield of the aquifers have probably lead to groundwater quality problems in the study area. The groundwater level contours indicate the regional slope trending to southwards, indicating the regional recharge zone probably lies in the northern part of the study area. Groundwater level contours also indicate the effluent nature of river Purna in a selected reach. The hydrochemical and stable isotopes (δ¹⁸O and δD) data indicate that salinity in the study area is due to the combined effect of a) evaporative enrichment of ions during the process of infiltration in the fine grained soil layers and b) dissolution of host formations as a result of longer residence time. The longer residence time is probably due to poor groundwater drainage conditions. This negates the hypothesis that the salinity is a result of drying-up of an inland lake filled with seawater, as proposed by some earlier investigators. Integrated use of hydrochemical and environmental isotopes indicate that about 72% of the induced recharge project wells being operated by GSDA are performing better and are reflecting improved recharge. The water quality in most of the project wells is also tending to become less saline