[GRASS-user] r.hazard.flood.py - GRASS 6.4.3RC2 WinXP

GRASS GRASS user
1

Hi,

This flood module is working in the latest stable release, however there is an issue in that it does not produce the flood ‘test1’ map only ‘test2’ (the MTI map). Running the module seems to generate three maps ‘r.clump’, ‘r.flood’ and ‘test2’. Just need confirmation that this is how it is meant to be and is the error below normal or does the module require fine tuning. Also is there any detailed information on this module? Where can i find it?.

r.hazard.flood.py map=mosaic@PERMANENT flood=test1 mti=test2
Cellsize : 5.0
SECTION 1a (of 4): Initiating Memory.
SECTION 1b (of 4): Determining Offmap Flow.
SECTION 2: A * Search.
SECTION 3: Accumulating Surface Flow with MFD.
SECTION 4: Closing Maps.
WARNING: Writing out only positive flow accumulation values.
WARNING: Cells with a likely underestimate for flow accumulation can no longer be identified.
Flow accumulation done.
Slope raster map <r_slope> complete
Slope map done.
Exponent : 0.0335464203571
MTI threshold : 2.64732051769
Calculating mti raster map…
Cleaning up…
Removing raster <r_accumulation>
Removing raster <r_slope>
Calculating flood raster map…
Running r.clump…
Pass 1…
Pass 2…
r.clump complete. 133745 clumps.
Deleting areas of less than 40000 cells…
‘r.area’ is not recognized as an internal or external
command,
operable program or batch file.
Invalid map <r_flood_th>
Invalid map <r_flood_th>
Parse error
ERROR: An error occurred while running r.mapcalc
(Thu Jan 17 11:54:55 2013) Command finished (7 min 8 sec)

–
Paul J. Shapley

2

Hi,

On Thu, Jan 17, 2013 at 1:37 PM, Paul Shapley <p.shapley@gmail.com> wrote:

Hi,

This flood module is working in the latest stable release, however there is an issue in that it does not produce the flood ‘test1’ map only ‘test2’ (the MTI map). Running the module seems to generate three maps ‘r.clump’, ‘r.flood’ and ‘test2’. Just need confirmation that this is how it is meant to be and is the error below normal or does the module require fine tuning.

you need to install r.area (addon).

Also is there any detailed information on this module? Where can i find it?.

This addon is based on an experimental procedure to detect flood prone area on the basis of DEM derivatives. A couple of papers have been produced about, [1] describes the development of the theory behind and [2] the implementation.

[1] Manfreda S., Di Leo M., Sole A., Detection of Flood Prone Areas using Digital Elevation Models, Journal of Hydrologic Engineering, (10.1061/(ASCE)HE.1943-5584.0000367), 2011.

[2] Di Leo M., Manfreda S., Fiorentino M., An automated procedure for the detection of flood prone areas: r.hazard.flood, Geomatics Workbooks n.10, 2011. (PDF)

This latter is free access, if you need the former and don’t have access, let me know and I’ll send you the author’s copy.

Regards,

madi

–

Margherita DI LEO
Postdoctoral Researcher

European Commission - DG JRC
Institute for Environment and Sustainability (IES). Unit H03 – FRC
Via Fermi, 2749
I-21027 Ispra (VA) - Italy - TP 261

Tel. +39 0332 78 3600
margherita.di-leo@jrc.ec.europa.eu

Disclaimer: The views expressed are purely those of the writer and may not in any circumstance be regarded as stating an official position of the European Commission.