RiverSim is a river basin model construction kit. It comes with a rich set of tools for representing the structures and operating policies you need to manage a watershed.

• RiverSim has been used successfully to manage floods in both simple and complex river basins.

• RiverSim has been used for long term watershed planning studies.

• RiverSim has been used to schedule short term hydropower and pumpback storage operations.

The standard set of features is quite powerful. There is, however, sure to be some situation that is not quite captured by the standard tools. Happily, RiverSim is designed to be modified so that it can economically handle those special situations. It is written in object-oriented code with an eye to growth. This designed-in extensibility has proven to be a major benefit over the development cycle leading to the present version of the software.

With RiverSim, you can get a custom model tailored for your watershed at far less cost than that normally associated with custom software development.

There are three modules in RiverSim, a simulation engine, an optional watershed runoff and snow melt module and an optional water accounting engine. These modules, while logically and physically separate, have controls that allow them to work together seamlessly.

• The simulator has its own window which exposes the structure of the river basin to be modeled and allows that structure to be modified. The simulation window provides controls to set the time step and the period of the model run. It also has controls to set the operating policies to be followed by the model. Finally, the simulation window has controls for composing reports from a model run and sending those reports to a spreadsheet for display and further analysis.

• The runoff module allows the watershed above the reservoir system to be modeled using the SCS unit hydrograph method. This module also uses a simple snow melt equation that handles rain on snow events. The watershed model is able to be run either independently or in conjunction with a reservoir model.

• The water accounting module has its own window which exposes controls to manage the ownership of water. The water accounting module integrates with a reservoir model.