CCHE1D uses ArcView® GIS to implement a graphical interface from which the user can control each step of the modeling procedure. It provides a system of dynamic menus and buttons that help and guide the user through the simulation processes, adding visual feedback for all operations and support for GIS data formats

Landscape Analysis

The CCHE1D graphical interface supports all functionality necessary for the creation of a channel network using the Landscape Analysis module. Given a Digital Elevation Model (DEM) file, CCHE1D utilizes the model TOPAZ to extract the drainage network. The CCHE1D generates all the necessary data entries required by the flow and sediment transport models

Channel Network Digitizing Interface

New for version 3.0 is the Channel Digitizing Interface, which allows the user to "draw" a channel network with the mouse on the computer screen, using any image image (such as a photograph, scanned map, or sketch), or GIS layer (shapefile, grid) as reference. CCHE1D algorithms convert the drawing into a complete CCHE1D channel network, creating all the necessary data entries. From a single channel to a complex drainage network, the new digitizing interface allows the user to create a complete input data set in minutes.

Control Module

The interface is tightly connected to the control module that, for each phase of the simulation, manages the execution of all programs and the flow of data among them. The control module is responsible for preparing the necessary input data, controlling the execution of the simulation, and storing the simulation results for use by another model. It makes use of a relational database that stores all the simulation data. The control module contains programs that perform data format conversions and transfers, and tools such as the automatic generation of a computational mesh for the channel simulations.

Data Conversion and Transfer

A large effort is necessary to make the output of the watershed model compatible with the input requirements of the channel model. The automated generation of channels and subwatersheds servers as a common point for the integration of the watershed and channel models.

CCHE1D converts the output of the landscape analysis TOPAZ from unformatted data files and tables into a relational database, which implements an enhanced description of the channel network and subwatersheds that facilitates the use of computed upland loads as input to the channel model. Computed daily water and sediment loads for each subwatershed are converted to triangular hydrographs and sedigraphs and assigned to nodes of the computational mesh.

Relational Database

CCHE1D maintains a relational database in which all relevant information is stored. The database is created when data derived from the channel network extraction process are converted and organized into a series of tables that describe the basic topology of the channel network and the corresponding subwatersheds. The database is automatically updated to respond to changes caused by user interaction or due to data generated or modified by the modeling programs.

Channel Network Analysis Module

The Channel Network Analysis Module consists in preparing a dataset that accurately describes the topology and physical properties of the drainage system, which will be used in the simulation of flow and sediment transport processes of the channel network. It includes the creation of a computational mesh and the supply of data describing channel properties, such as cross-sectional geometry, roughness, and bed and bank sediment data.

Simulation and Output Control

The channel flow and sediment transport analysis is entirely controlled from the graphical interface, which offers interactive tools that aid the user in defining simulation control parameters, model options, and requirements for the output of simulation results.

CCHE1D has a system for the detailed specification of the type and frequency of output of results from the channel model. An interactive, map-based interface allows the user to choose variables, locations, and frequency for output. The interface also provides a series of dialogs where the user can specify all options and parameters for the flow and sediment transport computations.