[GRASS-user] Question regarding r.lake?

[John Helly]

Hi Maris et al.

I have a question about how r.lake works.  I am using a DEM in UTM/11N with an elevation range from -49 to 153m and attempting to run r.lake against it to produce flooding layers.  However, it will not produce a lake above 0.0m in elevation.  I have tried a variety of elevations but they all only go to 0.0 meters.  Am I doing something wrong?

Any help is appreciated.

Thank you.
John.

*****************************************


r.lake -n --overwrite --verbose dem=NBC.BaseModel.UTM11N.NAVD88.1_8m_v02.grdclip.flipped.nc at PERMANENT wl=5 lake=NBC_5 xy=478183.13, 3617526.21
Lake depth from -54.556332 to 0.000000
Lake area 171287640.635203 square meters
Lake volume -2715258244.183949 cubic meters
Volume is correct only if lake depth (terrain raster map) is in meters
(Tue Jan 31 08:18:01 2012) Command finished (39 sec)                            
(Tue Jan 31 08:19:40 2012)                                                      
r.lake -n --overwrite --verbose dem=NBC.BaseModel.UTM11N.NAVD88.1_8m_v02.grdclip.flipped.nc at PERMANENT wl=5.0 lake=NBC_5 xy=478183.13, 3617526.21
Lake depth from -54.556332 to 0.000000
Lake area 171287640.635203 square meters
Lake volume -2715258244.183949 cubic meters
Volume is correct only if lake depth (terrain raster map) is in meters
(Tue Jan 31 08:20:20 2012) Command finished (40 sec)                             


|----------------------------------------------------------------------------|
 |                                                                            |
 |   Type of Map:  raster               Number of Categories: 255             |
 |   Data Type:    FCELL                                                      |
 |   Rows:         8881                                                       |
 |   Columns:      7987                                                       |
 |   Total Cells:  70932547                                                   |
 |        Projection: x,y                                                     |
 |            N: 3620275.4407297    S: 3602512.04121555   Res: 2.00015759     |
 |            E: 492504.21647433    W: 476529.78174709   Res: 2.00005443      |
 |   Range of data:    min = -49.556332  max = 153.344849                     |
 |                                                                            |
 |   Data Description:                                                        |
 |    generated by r.in.gdal                                                  |
 |                                                                            |
 |   Comments:                                                                |
 |    r.in.gdal input="/Users/hellyj/work/SLR002/data/NBC_Basemap/NBC.Base\   |
 |    Model.UTM11N.NAVD88.1_8m_v02.grdclip.flipped.nc" output="NBC.BaseMod\   |
 |    el.UTM11N.NAVD88.1_8m_v02.grdclip.flipped.nc"                           |
 |                                                                            |
 +----------------------------------------------------------------------------+


Cheers.
--------------
John Helly, University of California, San Diego / San Diego Supercomputer Center / Scripps Institution of Oceanography / 760 840 8660 mobile / stonesteps (Skype) / stonesteps7 (iChat) / http://www.sdsc.edu/~hellyj