[GRASS-user] Re: Hydroligics in grass

[Michael Barton]

I start with, which method is better depends in part on your needs and  
your data.

That said, we've done a lot of testing in my lab of the ability of  
these (and other modules like r.flow) to simulate overland flow. We've  
had the best results with r.watershed with the new multi-flow  
direction (MFD) algorithm implemented in GRASS 6.5 and 7.

Michael
____________________
C. Michael Barton
Director, Center for Social Dynamics & Complexity
Professor of Anthropology, School of Human Evolution & Social Change
Arizona State University

Phone: 480-965-6262
Fax: 480-965-7671
www: www.public.asu.edu/~cmbarton, http://csdc.asu.edu


On Dec 12, 2009, at 4:13 AM, grass-user-request at lists.osgeo.org wrote:

> Date: Fri, 11 Dec 2009 21:05:58 +0100
> From: Joop Goedbloed <jlgoedbloed at hetnet.nl>
> Subject: [GRASS-user] Re: Hydroligics in grass
> Cc: grass-user at lists.osgeo.org
> Message-ID: <4B22A626.4000304 at hetnet.nl>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Op 11-12-09 20:44, Joop Goedbloed schreef:
>> Hi Users on the list
>>
>> To trace back the overland flood mechanism in (sub)urban area I've
>> done some experiments in grass.
>> (Sub)urban areas has in general a sewer-system (combined or storm).
>> One of the design-parameters of a sewer is the maximal capacity of
>> rainfall, in most cases e sewer is design
>> to carry off about 20mm/h rain.
>>
>> In case of very heavy storm about 60 mm/h the sewer becoms full and  
>> an
>> overland flood mechanism come into being.
>>
>> I've a 5x5 meter grid DEM of the area.
>> In grass there are several modules to simulate overland flood.
>>
>> * r. terraflow
>> * r.watershed
>> * r.topmodel
>> * r.topidx
>> ...
>>
>> What is the most useful module(s) in grass to simulate overland flood
>> mechanism?
>>
>>
>> First I used the r.terraflow module the resulting accumulation map is
>> here:
>> Terraflow accumulation map <ftp://192.168.2.107/houtblerick/teracc.png 
>> >
>>
>> Using the r.watershed module resulting  streammap is here:
>> Watershed stream map <ftp://192.168.2.107/houtblerick/wsstream.png>
>>
>> In both maps the red boxes are the complaints of water flood
>> A foto of the real situation is here
>> Foto <ftp://192.168.2.107/houtblericj/Holleweg.jpg>
>>
>
> For the puctures try ftp://80.61.251.86/Houtblerick/
> there are the tree pictures.
>> Thanks
>>
>> Joop Goedbloed
>>
>
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: http://lists.osgeo.org/pipermail/grass-user/attachments/20091211/2e668bd0/attachment-0001.html