SWMM-USERS Digest - 6 Jun 2008 to 7 Jun 2008 (#2008-102)
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Topics of the day:
1. Slope property of the subcatchements
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Date: Sat, 7 Jun 2008 13:04:22 +0330
From: Bozorg <boz...@KOSAR.NET>
Subject: Re: Slope property of the subcatchements
Hello Stephanie ;
You can use SRTM, as Laurent C. proposed, if it's available in a suitable
resolution for your area. A worldwide coverage of the SRTM 90-m DEM is
freely available from e.g., here : http://srtm.csi.cgiar.org/
The Average Basin Slope may be estimated using the following simple relation
used in the UK FSR (NERC,1975) also quoted in the Roy Dodson's "Advances in
Hydrologic Computation" (chapter 23, David Maidment (editor), Handbook of
Hydrology, Mc Graw Hill,1993) as below :
Basin Slope = [(Elevation at 0.85 L) - (Elevation at 0.10 L)] / (0.75 L)
where L= the Length of the longest channel extended from the basin mouth to
the drainage divide.
It works for the rural basins and , bearing in mind what Mitch H. explained,
may serve as a first guess for the urban basins too.
Good Luck,
Mostafa Bozorg-Zadeh
Independent Consulting Engineer
----- Original Message -----
From: "Stephanie Piers de Raveschoot" <stephan...@EPFL.CH>
To: <SWMM-...@listserv.uoguelph.ca>
Sent: Friday, June 06, 2008 12:55 PM
Subject: [SWMM-USERS] Slope property of the subcatchements
Hello,
I was wondering: how can it be done if I have not been able to obtain the
slopes for every subcatchment in my real-case study ? Different slope values
will mean different peak flows, at different times, etc. Is there any way of
minimizing the impact of lack of correct slope values ?
Thank you,
Stephanie.
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End of SWMM-USERS Digest - 6 Jun 2008 to 7 Jun 2008 (#2008-102)
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