An area of influence defined by boundaries related to distance. In human geography, this area is defined as the location from which customers or visitors are attracted. In hydrology, this area defines the location within watershed boundaries (also known as a drainage basin).

learn more… | top users | synonyms

1
vote
0answers
36 views

QGIS 2.0 Catchment areas by using a 1 hour walking time

i would like to have catchment areas around my points which show the area of an one hour walk. I looked around and found information about using the hiking funktion for calculating a distance with the ...
0
votes
0answers
14 views

-1 value in NextDownId attribute in drainageline

I'm currently working on adjoining catchments in Arc Hydro Tools and I have noticed that there are catchments that are not adjoined. I checked all the generated datasets and found out that the ...
2
votes
1answer
88 views

How to create a catchment from a point using a DTM raster in QGIS?

I need to find a better way to delineate a catchment from a given point on a watercourse using a DTM - currently I am either using FEH, or if the catchment is too small using contours to draw ...
1
vote
1answer
138 views

catchment area using SAGA and Arcgis 10.2

I would like to calculate catchment area. I used D8 algorithm and running in both arcgis 10.2 and SAGA GIS 2.1.2. However, the results from two software are different. The lowest value of catchment ...
0
votes
0answers
34 views

Delineating catchments using GRASS GIS?

I am trying to delineate catchment using GRASS. Can anybody point me to "easy to understand" type of notes for GRASS? Will appreciate any help.
1
vote
1answer
80 views

Managing large number of catchments/watersheds

Does anyone know of an easy way to manage a large number (10,000's) of catchments/watersheds? I have defined a stream network and for each segment, I have a corresponding catchment (in a unique ...
0
votes
1answer
139 views

Efficient algorithms for recovering watershed boundaries?

This is somewhat related to a previous question I asked: What Algorithm is used by ArcGIS Watershed tool? I was wondering if there is a more efficient way to calculate catchment areas if you are ...
1
vote
1answer
38 views

How to compute drive access to a station based on vehicle origin points? [closed]

I have a shapefile that contains station locations and another shapefile that is the geocoded origins of those who drove to the station. I would like to make a buffer around the station that shows the ...
0
votes
1answer
99 views

How to create a catchment area using LSOA and point file data [closed]

I have to create a catchment area (based on LSOA) for the 19 underground stations within Camden borough and it has to be in a polygon vector file. I know I have to somehow group the SOAs but don’t ...
0
votes
0answers
142 views

How to calculate Gradient from DEM?

I have a digital elevation model for a catchment area and I would like to calculate the gradient by cells. Is that possible and does anybody know the steps?
4
votes
2answers
371 views

Find locations of raster maximum within polygons: Basin Delineation

I'm trying to identify the Location (lat/lon) and upstream area of every raster point that flows into the Arctic Ocean (there are a lot so it has to be fully automated). I'm starting with the ...
3
votes
1answer
911 views

How to obtain statistics within a Buffer/Catchment in MapInfo?

I need to calculate the population statistics within a 10 minute drivetime catchment from a point and within 1 Km Buffer from a point in MapInfo, how can I do that can someone please elaborate? I have ...
5
votes
1answer
259 views

Creating dynamic links between features

I currently want to create links between 2 features. Ie., I have 2 basins that flow out and I want to use a line/polyline to have a link out of them and both point to a common 3rd feature, indicating ...
3
votes
3answers
2k views

River drainage basin boundary

I'm looking for a set of outlines of the river basins in the UK - I don't need a particularly detailed or highly accurate map - just a map saying point X will drain into the Thames or point Y will ...
7
votes
2answers
717 views

Is there a described GIS method for creating catchment areas based on nearest driving distance?

ie. a combination of Voronoi polygons with isochrones, so that the Voronoi polygons are based on driving distance instead of Euclidean distance. Is there a name or a described method for this?