[GRASS-user] r.flow: define contributing area

[Johannes Radinger]

Rich,

Maybe have a look at r.lake: https://grass.osgeo.org/grass70/manuals/r.lake.html. This module fills the area upstream a dam or a blocked stream.

Cheers,
Johannes



<div>-------- Original message --------</div><div>From: Thomas Adams <tea3rd at gmail.com> </div><div>Date:04/10/2016  04:32  (GMT+01:00) </div><div>To: Rich Shepard <rshepard at appl-ecosys.com> </div><div>Cc: grass-user at lists.osgeo.org </div><div>Subject: Re: [GRASS-user] r.flow: define contributing area </div><div>
</div>Rich,

The only way to -correctly- do this is with hydrodynamic modeling, such as with HEC-RAS. It can be very crudely approximated with r.damflood (https://grass.osgeo.org/grass70/manuals/addons/r.damflood.html).

Tom

On Mon, Oct 3, 2016 at 7:39 PM, Rich Shepard <rshepard at appl-ecosys.com> wrote:
  Reading the r.flow manual page suggests that the use of the '-u'
(upstream) option allows determination of flowlines and lengths that can be
used to delineate the area that would drain to a specific point. Is this
correct?

  To determine the area flooded if an outlet is plugged would require the
inverse of r.drain. That module calculates the area flooded with surface
water originating from a specific point; e.g., a hole in a dike or dam. The
closest I've seen to do the opposite seems to be r.flow. The quantity of
surface water and the rate of accumulation and infiltration into the vadoz
zone are not of interest, only the area flooded is needed.

  The modules listed under the Natural Hazards application page all appear
to delineate the area flooded from a point source. Can any of these be used
backwards to delineate the area flooded if an outlet is blocked?

  I'd appreciate pointers and suggestions based on cumulative experience
here for appropriate module(s).

TIA,

Rich
_______________________________________________
grass-user mailing list
grass-user at lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/grass-user




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/grass-user/attachments/20161004/d9346793/attachment.html>