[GRASS-user] WPS with GRASS and PyWPS

GRASS GRASS user
1

Dear list

We have developed a Web Processing service for calculating catchment
outlines in UK using GRASS and PyWPS:

http://www.faunalia.co.uk/catchmentfinder

Any feedback is appreciated.

Regards
Saber

2

Valentin

Many thanks for your feed back.

The DTM is quite old (over 20 years) and very coarse (50 metre..but grass
region setting is I think 100 metre).

The reason you don't see the point is that it doesn't use the point and it
uses another one snapped to the stream (r.watershed output). But we
definitely add something to show the point, either user input or the
snapped one.

In terms of validation, we have Flood Estimation Handbook which
unfortunately is not free and using the same DTM in our WPS. For copyright
reasons there is no vector output from FEH either. So you need to create
screenshots. I don't have a license for it.

There will be more bells and whistles to it (hydrological parameters:
urban extent, main drain slope, max min elevation, etc).

Cheers
Saber

Nice tool, I like it!

Three things came up in my mind when I used it.

1) After I selected a point and press calculate I couldn't see any more
the point I selected...

2) It seams like there are some wrong calculation. For example for the
randomly chosen point (527714, 328638). And the catchment border could
be a little smoother :wink:

3) I can only select a visual point, it would be nice to select the
point by coordinates... it would be more useful.

Did you try to validate your data with a independent dataset? I know
from France there exists free hydrological surface catchments shapes
over the whole country maybe it possible to make a validation with
public DEM-data like SRTM.

regards Valentin

On Oct 26, 2011 9:27 AM, "Saber Razmjooei" <razmjooeis@faunalia.co.uk
<mailto:razmjooeis@faunalia.co.uk>> wrote:

    Dear list

    We have developed a Web Processing service for calculating catchment
    outlines in UK using GRASS and PyWPS:

    http://www.faunalia.co.uk/catchmentfinder

    Any feedback is appreciated.

    Regards
    Saber

    _______________________________________________
    grass-user mailing list
    grass-user@lists.osgeo.org <mailto:grass-user@lists.osgeo.org>
    http://lists.osgeo.org/mailman/listinfo/grass-user

3

Dear Valentin

Thanks for your through inspection. That part of UK is flat with lots of
artificial drains and canals. There is a loop river and also 2 parallel
channel. The DTM doesn't look great either and I think streams have not
been extracted properly in r.watershed.

Cheers
Saber

On 26/10/11 21:07, Valentin Wittich wrote:

Hi Saber,

could you recreate the wrong calculation I've get with the point
(527714, 328638). The point is a little above the connection to the
tributary, could it be that the snap function doesn't work proper?

V.

On 10/26/2011 12:08 PM, Saber Razmjooei wrote:

Valentin

Many thanks for your feed back.

The DTM is quite old (over 20 years) and very coarse (50 metre..but
grass
region setting is I think 100 metre).

The reason you don't see the point is that it doesn't use the point
and it
uses another one snapped to the stream (r.watershed output). But we
definitely add something to show the point, either user input or the
snapped one.

In terms of validation, we have Flood Estimation Handbook which
unfortunately is not free and using the same DTM in our WPS. For
copyright
reasons there is no vector output from FEH either. So you need to create
screenshots. I don't have a license for it.

There will be more bells and whistles to it (hydrological parameters:
urban extent, main drain slope, max min elevation, etc).

Cheers
Saber

Nice tool, I like it!

Three things came up in my mind when I used it.

1) After I selected a point and press calculate I couldn't see any more
the point I selected...

2) It seams like there are some wrong calculation. For example for the
randomly chosen point (527714, 328638). And the catchment border could
be a little smoother :wink:

3) I can only select a visual point, it would be nice to select the
point by coordinates... it would be more useful.

Did you try to validate your data with a independent dataset? I know
from France there exists free hydrological surface catchments shapes
over the whole country maybe it possible to make a validation with
public DEM-data like SRTM.

regards Valentin

On Oct 26, 2011 9:27 AM, "Saber Razmjooei"<razmjooeis@faunalia.co.uk
<mailto:razmjooeis@faunalia.co.uk>> wrote:

     Dear list

     We have developed a Web Processing service for calculating
catchment
     outlines in UK using GRASS and PyWPS:

     http://www.faunalia.co.uk/catchmentfinder

     Any feedback is appreciated.

     Regards
     Saber

     _______________________________________________
     grass-user mailing list
     grass-user@lists.osgeo.org<mailto:grass-user@lists.osgeo.org>
     http://lists.osgeo.org/mailman/listinfo/grass-user