The Water Resources Division of the U.S. Geological Survey is developing a National Water Information System (NWIS) that will integrate and replace its existing water data and information systems of the National Water Data Storage and Retrieval System, National Water Data Exchange, National Water-Use Information, and Water Resources Scientific Information Center programs. It will be a distributed data system operated as part of the Division 's Distributed Information System, which is a network of computers linked together through a national telecommunication network known as GEONET. The NWIS is being developed as a series of prototypes that will be integrated as they are completed to allow the development and implementation of the system in a phased manner. It also is being developed in a distributed manner using personnel who work under the coordination of a central NWIS Project Office. Work on the development of the NWIS began in 1983 and it is scheduled for completion in 1990. This document presents an overall plan for the design, development, implementation, and operation of the system. Detailed discussions are presented on each of these phases of the NWIS life cycle. The planning, quality assurance, and configuration management phases of the life cycle also are discussed. The plan is intended to be a working document for use by NWIS management and participants in its design and development and to assist offices of the Division in planning and preparing for installation and operation of the system. (Author 's abstract)