Composite Web Information System for Management of Water Resources Nenad Stefanovic & Ivana Radojevic & Aleksandar Ostojic & Ljiljana Comic & Marina Topuzovic Received: 23 July 2014 /Accepted: 20 January 2015 / Published online: 3 February 2015 # Springer Science+Business Media Dordrecht 2015 Abstract Management of water resources such as lakes and reservoirs involves many stake- holders and a huge amount of data that comes from various information systems and in different formats. These systems are typically very difficult to integrate, analyze and custom- ize. This requires a new breed of information systems capable to answer the challenges of modern water information management. In this paper, we introduce the new application model for designing such systems and accompanying i-SeLaR software system - composite, service- oriented and multilayered web information system for management of Serbian lakes and reservoirs. We describe architecture and services of the application model, together with structure and functionalities of the software solution. i-SeLaR integrates data, tools and applications for collaboration, data and knowledge management, process automation, and analytics. Architecture and features of i-SeLaR provide scalability and flexibility, so the system can be scaled, customized and implemented in organizations of different types and sizes. i- SeLaR web portal is the central component which serves as a unique gateway to different data sources and services, and provides a seamless and unified web interface for monitoring and management of water resources. Practical results showed several benefits in terms of better integration and flexibility, enhanced collaboration, higher data quality, knowledge-based analysis and more informed decision making. Water Resour Manage (2015) 29:2285–2301 DOI 10.1007/s11269-015-0941-y N. Stefanovic (*) Institute of Mathematics and Informatics, Faculty of Science, University of Kragujevac, Radoja Domanovića 12, 34000 Kragujevac, Serbia e-mail: nenads@kg.ac.rs I. Radojevic : A. Ostojic : L. Comic : M. Topuzovic Institute of Biology and Ecology, Faculty of Science, University of Kragujevac, Radoja Domanovića 12, 34000 Kragujevac, Serbia I. Radojevic e-mail: ivana@kg.ac.rs A. Ostojic e-mail: ostojic@kg.ac.rs L. Comic e-mail: ljilja@kg.ac.rs M. Topuzovic e-mail: marina@kg.ac.rs