This chapter describes the basic data requirements for performing the one-dimensional flow calculations within HEC-RAS. The basic data are defined and discussions of applicable ranges for parameters are provided. For information of data requirements for 2D modeling, please review the 2D Modeling User's manual.
The main objective of the HEC-RAS program is quite simple - to compute water surface elevations at all locations of interest for either a given set of flow data (steady flow simulation), or by routing hydrographs through the system (unsteady flow simulation). The data needed to perform these computations are divided into the following categories: geometric data; steady flow data; unsteady flow data; sediment data; and water quality data. Geometric data are required for any of the analyses performed within HEC-RAS. The other data types are only required if you are going to do that specific type of analysis (i.e., steady flow data are required to perform a steady flow water surface profile computation). The current version of HEC-RAS can perform either steady or unsteady flow computations.
Note
This Chapter discusses the basic data for one-dimensional modeling. For discussions on 2D modeling, please review the HEC-RAS 2D Modeling Users Manual.
