River Reach Definitions

Particular rivers or reaches for the analysis can be defined from the LifespanDesign, VolumeAssessment and ModifyTerrain modules, referring to:
ModifyTerrain/.templates/computation_extents.xlsx
The concerned modules provide options for reach differentiation and limit calculations to defined particular reaches. These limitations are automatically used by the other modules. This subdivision of the computation domain enables the analysis of up to eight reaches per copy of River Architect. The below figure illustrates the workbook spreadsheet for reach delineation. Changes can be effected by clicking on the Reaches dropdown menu and then DEFINE REACHES, or directly in the folder ModifyTerrain/.templates/. In order to ignore any reach definitions, select IGNORE (use Raster extents).

If the workbook is accidentally deleted or irreparable, incorrect modifications were made, there is an offline backup copy available:
ModifyTerrain/.templates/computation_extents - Copy.xlsx

ModifyTerrain/.templates/computation_extents.xlsx can be opened, for example, by clicking on the Reaches drop-down menu (ModifyTerrain module) and then “DEFINE REACHES”. The extents need to correspond to the input DEM coordinate and unit system types (e.g., a georeference may be GRS_1980_Lambert_Conformal_Conic with the linear unit of Foot_US). If the reaches 00 to 07 align from the East to the West, the Max x value of a reach corresponds to the Min x value of the next upstream reach. If a reach is situated in the south of its upstream reach, its Max y value corresponds to the Min y value of the upstream reach. Such gap-less transitions enable consistent mapping of DEM differences and excavation/fill volume calculations.
After editing, saving and closing the spreadsheet, the GUI window can be updated by clicking on the Reaches drop-down menu and then “RE-BUILD MENU”. Whatever name is stored in the workbook, River Architect uses internal identifiers that point at the rows in the spreadsheet, and therefore, output rasters are enumerated with tags r00, r01, … r07.
All reaches can be deselected by clicking on “CLEAR ALL” to add particular reaches only. If more than five reaches are selected, the GUI truncates the list and displays Many / All.

The code handlers for reaches are part of riverpy (RiverArchitect/.site_packages/riverpy/). The Reaches class in cDefinitions.py flexibly sends reach information to all modules and reads reach information using the Read class in cReachManager.py. The dictionaries and lists of the Reaches class include an additional entry called "none": "none" / "Raster extents" to enable reach-independent analyses.