The development of quantitative fluvial research has been closely tied with the classification of stream network. Historically, both qualitative and quantitative systems of stream classification have evolved in response to ever-changing needs and scientific environment. All current classifications, however, are based solely on the channel network topology whereas the geometry, hydrology, water budget, form and fabric of the drainage basin are ignored. Another problem with current methods of stream description is the amount of computation necessary to ascertain the characteristics of streams of any given class. Thus, these advanced research systems are rarely used in applied stream studies. The WATER System is presented as a computer augmented method for collection, storage, and analysis of real river networks. Its purpose is to facilitate the application of advanced fluvial analysis to actual problems of water management and river control. Data are collected so that geometry as well as topology of a stream is preserved. (Author)