Digitising surface water with GIS

ı am currently ​working on a ​project for ​digitizing ​water resources.

May I ask you how you understand the canal flow direction when digitizing these kinds of water bodies.

If you know any technique, please let me know. Much appreciated.

Taxonomy

• GIS & Remote Sensing Technology
• GIS
• Groundwater Assessment
• Groundwater Modeling
• Groundwater Mapping
• Surface Flow Analysis
• GIS & Remote Sensing

9 Answers

1. Hi Erdem,

   The suggestions so far are quite handy.

   I wouldn't agree more. A Digital Elevation Model (DEM) with a good resolution will be very helpful.

2. Hi Erdem. You can use Digital Elevation Model (DEM) of your consider area or basin. By the use of ArcGIS software>> the section of Hydrology, you can draw the maps of flow direction and flow path for surface waters based on the direction of slope achieved from DEM.

   Good Lock 

3. Hi Erdem. I have done this using two methods depending on the system and data availability. The answers about using a DEM are correct and in the UK we now have a recent DEM of high accuracy and at 5m postings. However more historically digitising linear water features to encode flow direction has been carried out by setting up a rule for this feature type in the system. The rule stated that digitisation was always in the upstream direction and end node codes used to manage the connectivity.

4. The problem of define flow direction is very easy when you have a data on local topography

   In many cases when there is a flat topography it's can be tricky

   You can use the elevation profile from google earth to find the general elevation profile along your canal , the other option is to use the data from DEM. There is a good DEM from the Japan Aerospace Exploration Agency (JAXA)

   https://www.eorc.jaxa.jp/ALOS/en/aw3d30/index.htm

   please note that both data set are based on 30m grids **

     

   Good luck

   Lior .

     

5. You can use PyDEM python library (https://github.com/creare-com/pydem).

6. I would start by looking where the water sources are that supply the canal and their relationship with locks this way you should be able to get the hydraulic gradient without too muchfield testing

7. DEM of the region is necessary.

   1 Comment

   1. ı have already DEM data

8. You can use Alu to get it to downfall

   1 Comment

   1. Use your DEM as guidance. If you ha that available.

      1 Comment reply

      1. I have already DEM data but sometimes they can not a solution to determine water flow directions, especially flat places

9. Dear erdem,

   knowing water surface elevation at known points ..... water flows from higher elevation to lower elevation.

   regards