www.cafetinnova.org Indexed in Scopus Compendex and Geobase Elsevier, Geo-Ref Information Services-USA, List B of Scientific Journals, Poland, Directory of Research Journals ISSN 0974-5904, Volume 09, No. 06 December2016,P.P.2759-2764 #02090662 Copyright ©2016 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved. Effects of Treated Wastewater Irrigation on Soil Properties–A Case Study at NIT Trichy ANTONY RAJ, SARAVANAN S AND MANJULA R Department of Civil Engineering, National Institute of Technology Tiruchirappalli, Tiruchirappalli, India Email: rajeshalamuchandran@gmail.com, ssaravananirs@gmail.com, manju@nitt.edu Abstract: This study was carried out to investigate the effect of treated wastewater on soil physical, chemical and biological properties. Field experiment was conducted in NIT Trichy region in Trichy with treated wastewater and groundwater surface irrigation systems for crops of Teak wood farm and Hibiscus rosa-sinensis. The quality of treated wastewater was studied to evaluate the performance of treatment units and the suitability of treated wastewater for irrigation. The irrigation system had a significant effect on infiltration rate, bulk density and total porosity. The soil samples were taken from the farm with an area of more than five acres and nine sample points were picked spatially throughout the field. A research project was undertaken to determine the role of physical and chemical soil properties in the treatment performance of subsurface effluent disposal areas. Monitoring changes in these properties will permit improved prediction of the treatment potential of a soil. The changes within soil properties of the disposal area due to effluent application were found to be directly related to the subsurface drainage characteristics including permeability, clay content and pore size. The major controlling soil physical and chemical attributes were found to be moderate drainage, significant soil cation exchange capacity and dominance of exchangeable Ca or exchangeable Mg over exchangeable Na and low exchangeable Na. An in-depth knowledge of the local soil characteristics and associated soil hydrology is needed for better prediction of long term behaviour of subsurface effluent disposal systems. . The growth of plants at the control points are also monitored for growth pattern. The goal of this study is to evaluate, on short period, the effects of the TWW irrigation, in comparison to that of the Ground Water, on the physical, chemical and biological properties of soil cultivated with Teak wood and never irrigated by TWW. Keywords: Treated wastewater, Soil properties, Irrigation, Exchangeable cations, Nutrients 1. Introduction Soil structure is considered a key factor in the functioning of soil, as its ability to support plant and animal life, and moderate environmental quality (Bronick and Lal, 2005). Several methods of soil structure assessment have been proposed and tested around the world. In general, methods of soil structure assessment are divided in to direct and indirect methods. Indirect characterization of soil structure includes its estimation from soil properties such as hydraulic conductivity, infiltration rate, bulk density (BD) and pore-size distribution (Pagliai et al., 2004; Kodesova et al., 2011; Guimaraes et al., 2013). The reuse of treated wastewater (TWW) in agricultural purposes has been increasingly considered to be beneficial for crop production, and due to its significant source of nutrients for the plants it can help to reduce the requirements for commercial fertilizers. It is promoted in order to save fresh water for water supply and to protect receiving waters. It comes very handy in arid and semiarid regions. (Jemai et al., 2013). There is a gradual decline in availability of fresh water to be used for irrigation in India. As a consequence, the use of sewage and other industrial effluents for irrigating agricultural lands is on the rise particularly in peri-urban areas of developing countries. On the other hand, there is increasing concern regarding the exceedance of statutory and advisory food standards for trace metals throughout the world. (Rattan et al., 2005). The reuse of treated wastewater for irrigation is a practical solution to overcome water scarcity, especially in arid and semiarid regions. (Al Jaboobi et al., 2014). Irrigation with municipal wastewater could change soil properties that play an important role on the amount and availability of nutrients present in the applied wastewater (Magesan et al., 1998). In particular, soil physical properties such as texture, structure, porosity, and hydraulic conductivity will influence soil water content and aeration, which in effect control the type and rate of soil microbial activity and chemical reactions (Magesan et al., 2001). A research study was undertaken to determine the role of physical and chemical soil properties in the treatment performance of subsurface effluent disposal areas. Monitoring changes in these properties will permit improved prediction of the treatment potential of a soil.. The major controlling soil physical and chemical attributes were found to be moderate drainage, significant soil cation exchange capacity and dominance of exchangeable Ca or exchangeable Mg over exchangeable Na, low exchangeable Na, soil type. (Dawes et al., 2004). Chronological