How to generate Star Hydro datasets?

Star Hydro analysis starts with loading of terrain maps.

Layers required to perform analysis are:

Projected terrain

Pit filled terrain

Flow accumulation

Flow direction (D8)

Star Hydro at this time (7/9/2007) assumes that all layers coordinates are in meters.

At this time it is suggested to place files in:

$HOME/starhydro_workspace/StarHydro and load them using "File->Open->StarHydro".

On Windows XP folder is usually:

c:\documents and settings\(your user name)\starhydro_workspace

On Mac OS X and Linux it is:

/home/(your user name)/starhydro_workspace

I'm working on File manager that will make this easier.

USGS seamless map can be converted to Star Hydro using Arc Workstation using following scripts:

Gridname is the name of the grid in the Arc Workstation's workspace

Projectionfile is the file describing input paramters and output units (ZUNITS METERS, UNITS METERS).

%% Project using projection file from below

project grid gridname projected projectionfile

gridascii projected projected.xyz

%% Pit filling using ESRI fill method

grid

fill projected filled sink

quit

gridascii filled filled.xyz

%% Calculate flow direction

grid

flowdir = flowdirection( filled )

quit

gridascii flowdir flowdir.xyz

%% Calculate flow accumulation

grid

flowacc = flowaccumulation( flowdir )

quit

gridascii flowacc flowacc.xyz

---

%% To find original grid projection parameters use:

describe gridname

Sample projection parameters (projectionfile.prj):

INPUT

Projection GEOGRAPHIC

Datum NAD83

Zunits METERS

Units DD Spheroid GRS1980

PARAMETERS

OUTPUT

PROJECTION UTM

DATUM NAD83

ZONE 18

ZUNITS METERS

UNITS METERS

PARAMETERS

END