Development and Application of a Nowcast and Forecast System Tool for Planning and Managing a River Chain of Lakes

Abstract

A nowcast and forecast system for providing real-time water information of a River Chain of Lakes (RCL) is developed. The system infrastructure comprises a web portal to retrieve and display observations that are used to drive models under a high performance computing server. Water level and flow discharge information are obtained from a suite of models that be directly simulate the RCL system. A new data assimilation technique based upon flow routing algorithm and nested-mesh domain reduction is developed to update the Manning's roughness. It is demonstrated that the INFOS can reliably and effectively model real-time reverse flows due to sustained wind forcings or tranisent seiches, and flow choking due to channel constriction. Applications of the developed system are illustrated. Specifically water level planning scenarios provide a quantitative measure for lake management to reduce floods under extreme rainfall events. Alternative management philosophies to minimize exceeding the water level orders are evaluated. Overall, the Integrated Nowcast and Forecast Operation System (INFOS) provides reliable and timely water information for the RCL for sharing information to the community, planning for water use and delivery, and management of the Yahara RCL.