WMS:GSSHA

Gridded Surface Subsurface Hydrologic Analysis (GSSHA) is a two-dimensional finite difference rainfall/runoff model. A finite difference grid is used to establish the computational domain and parameters for surface runoff. The GSSHA model is fully coupled with hydraulic stream flow/routing models. Parameters for stream channels are defined using arcs and then mapped to the appropriate underlying grid cells.

Features of GSSHA include 1D stream flow and infiltration, 2D overland flow and groundwater, and full coupling between the groundwater, shallow soils, streams, and overland flow. "Sediment and constituent fate and transport are simulated in the shallow soils, overland flow plane, and in streams and channels. GSSHA can be used as an episodic or continuous model where soil surface moisture, groundwater levels, stream interactions, and constituent fate are continuously simulated. The fully coupled groundwater to surface-water interaction allows GSSHA to model basins in both arid and humid environments."

The GSSHA model can be added to a paid edition of WMS.

GSSHA Menus

There are two GSSHA menus in WMS:

• When in the Map module, the GSSHA menu is available when a GSSHA coverage is selected. See WMS:GSSHA Menu#GSSHA Coverage Menu for more details.
• When in the 2D Grid module, the main GSSHA menu is available. See WMS:GSSHA Menu#GSSHA Grid Menu for more details.

GSSHA File Types

The following are files types used in GSSHA. Many of the output files can also be used as input files.

AQE

GSSHA lower extent of the aquifer file

CDP

GSSHA channel flow depth output file in link/node format

CDQ

GSSHA channel discharge output file in link/node format

CIF

GSSHA channel input file

CMT

GSSHA area property mapping table file

CST

GSSHA channel stage output file in link/node format

CVT

GSSHA channel velocity output file in link/node format

DEP

GSSHA overland flow depth maps file

DHT

GSSHA channel depth hot start file

DIK

GSSHA file containing no-flow embankments between overland grid cells

DRN

GSSHA rainfall rate as it is being applied

DSC

GSSHA overland discharge output file

ELE

GSSHA surface grid/cell elevation file

EXT

GSSHA replacement parameter or value file

FGD

GSSHA maximum water depth on the overland grid output file

FST

GSSHA maximum water depth on the stream network output file

GAG

GSSHA gaged or radar precip data input file

GST

GSSHA grid/stream file

GWH

GSSHA groundwater heads file

IDP

GSSHA infiltration depth file

IDX

GSSHA cell index file

IHL

GSSHA hydrograph output locations file

ITH

GSSHA soil moisture output locations file

LSP

GSSHA file containing low spots for overtopping on the embankments

MAP

WMS map file

MSK

GSSHA watershed delineation mask file

OAL

GSSHA gridded output file of overland algal mass and concentration

OCB

GSSHA gridded output file of overland CBOD mass and concentration

ODO

GSSHA gridded output file of overland DO mass and concentration

ODP

GSSHA gridded output overland depths file, written at the end of the simulation

OHL

GSSHA hydrograph output file

ON2

GSSHA gridded output file of overland NO2 mass and concentration

ON3

GSSHA gridded output file of overland NO3 mass and concentration

ON4

GSSHA gridded output file of overland NH4 mass and concentration

OON

GSSHA gridded output file of overland ON mass and concentration

OOP

GSSHA gridded output file of overland OP mass and concentration

OP4

GSSHA gridded output file of overland PO4 mass and concentration

OPT

GSSHA values of event peak flow and event volume for use by external optimization methods output file

OTH

GSSHA soils moisture time series output file

OTL

GSSHA outlet hydrograph time series discharge file

OUT

GSSHA output summary file

OVN

GSSHA roughness file

PRJ

GSSHA project file

PRO

GSSHA projection file

QHT

GSSHA channel flow hot start file

SMO

GSSHA soil moisture output file

SMT

GSSHA streams mapping table file

SRC

GSSHA point and non-point loadings file

STO

WMS stochastic information file

SUM

GSSHA summary output file

TON

GSSHA gridded output file of total N mass and concentration

TOP

GSSHA gridded output file of total P mass and concentration

TRE

WMS tree file

TS

GSSHA time series input file

WTE

GSSHA initial water table elevation file

Cell Properties

The 2D grid cell properties include an I,J location and a scalar or index map value. The scalar or index map value is associated with the currently selected dataset in the Project Explorer and can be edited in the Properties Window. The I,J location can be viewed but not dited in the Properties Window. The 2D grid contours are a way of visualizing the spatial variation of the scalar or index map values for the selected dataset.