Geometry Dataset Requirements

A geometry dataset is required for all water quality models and represents the water quality (WQ) domain, which includes the river-reservoir network connectivity and discretization information. The geographic extent of the geometry dataset (set by the selected HEC-ResSim network) can be subdivided into regions used for grouping watershed elements that share the same water quality parameters.
The geometry dataset is created based on an HEC-ResSim network, and an imported HEC-RAS geometry shapefile and steady flow model output file (refer to Section 4.3 for instructions on creating and defining the geometry dataset). The HEC-RAS geometry shapefile is used to establish the water quality cells, by default a single cell is configured between HEC-RAS cross-sections. The default water cell configuration can be adjusted if necessary, as described in Section 4.7.
Further, for water temperature modeling the geometry dataset is linked to a meteorological dataset (refer to Chapter 3). The meteorological dataset is used by the geometry dataset (refer to Section 4.9) to assign each reach and reservoir to a met station in the linked meteorological dataset. When linked to a meteorological dataset, each water cell (defined in the geometry dataset, see Section 4.3) in the water quality model is individually assigned to a particular met station in the meteorological dataset.
The pre-requisites for completing the geometry is the creation of the HEC-ResSim network, HEC-RAS geometry file, HEC-RAS steady flow file, and Meteorological Dataset. Note, this manual is supplemental to the HEC-ResSim User's Manual, and users should refer to the HEC-ResSim Version 4.0 for general HEC-ResSim software information. Refer to the HEC-RAS User's Manual for information regarding the HEC-RAS geometry shapefile and steady flow file.
Note, the geometry dataset is used when creating a WQ Parameters set (Chapter 6), Initial Conditions set (Chapter 9), Boundary Conditions set (Chapter 8), Dispersion Coefficient set (Chapter 10), and a Mass Injection dataset (Chapter 11).