GeoIS-EM Home         Panama and Chagres River Watershed Analysis

Helena Mitasova, NCSU

When using the images posted here, please credit this site as:
Mitasova, H. 2003-2006, Panama Watershed Analysis,
http://skagit.meas.ncsu.edu/~helena/measwork/panama/panama.html

GIS data processing is performed for the ARO project: Chagres River Tropical Watershed Study

Panama DEM, based on SRTM 90m resolution data
Entire Panama DEM
Panama DEM, analyzed subset with extracted main rivers
Panama rivers

Preliminary Panama watersheds analysis based on SRTM 90M resolution DEM

Main rivers and watersheds, 83-82deg west
All extracted streams 83-82deg west
Main, 82-81 deg west
All, 82-81 deg west
Main, 81-80 deg west
All, 81-80 deg west
Main, 80-79 deg west
All, 80-79 deg west
Main, 79-78 deg west
All, 79-78 deg west
The straight lines are in areas with large water bodies. There are few small areas with no-data (holes), mostly in mountains - those areas will be reinterpolated. For the Central Panama see maps for Chagres, Pequeni, Cuango and Pacora basins below with more detailed analysis based on IFSARE data.

The entire analysis can be done in hours instead of days using r.terraflow
SRTM DEM with major rivers extracted by r.terraflow
SRTM DEM with more detailed stream network extracted by r.terraflow

Watershed analysis for Pequeni, Cuango and Pacora basins (50m resolution)

Location of sites sampled in Jan. 2006
Location of old and new sites sampled
All studied basins and streams; 2005 sites
Flowaccumulation and sites for all studied basins
Flowaccumulation and sites for northern basins
Flowaccumulation and sites for Pacora basin
Chagres and northern basins and streams
Pequeni basin and stream network
Section of Pequeni basin stream network with lower threshold (10m resolution DEM)
Pacora flow accumulation at 30m res draped on terrain
Pacora flow accumulation at 30m res (2D) (note that 50m res. result fixes the confluence with T river)

DEM, streams, field sites

Images based on 25m and 50m resolution analysis

• DEM, fault lines (old)

• 3D view entire Chagres: points, elevation, streams in- and out-side
  
• 3D view entire Chagres : points, elevation, streams, masked
  
• 3D view entire Chagres: points, stream direction, masked
  

• 2D sub-basins and stream network
• 2D Shaded DEM, streams, field sites
• 2D flow accumulation
• 2D stream directions, field sites
• 2D stream directions, field sites, masked
• 2D stream directions, field sites, masked, 1km grid

• 3D view : points, elevation, streams, North Chagres
  
• 3D view : points, stream direction, North Chagres
• 3D view : points, elevation, streams, South
  
• 3D view : points, stream direction, South
  
• Zoom-in - streams direction and points
  

Comparison of stream extraction tools

• Suggested test areas for stream extraction comparison
• Rivertools (10m), r.watershed (25m) stream networks and field points - central section
• same as above for NE section
• Rivertools (10m, vector), r.watershed (10m, raster) stream networks and field points - central section
• Rivertools (10m, vector), r.watershed (10m, raster) stream networks and field points - central section
• Rivertools (10m, vector), r.watershed (10m, pink raster), r.terraflow (10m, grey raster) stream networks and field points - central section
• Upper Chico: r.watershed (25m, raster), stream confluence is captured properly
• Upper Chico: Rivertools (10m, vector), stream confluence is completely missed
• Upper Chico: 3D view of original topograpy with streams by Rivertools (10m, vector), note that the area is not flat - the flat was created by basin fill
• assessing the accuracy using point-in-buffer, example is for 25m resolution r.watershed result with buffers

High resolution (10m) images for February 2003 study areas

go to
http://skagit.meas.ncsu.edu/~helena/measwork/panama/
and download map*.jpg images
Lower left (SW) coordinates for the UTM grid for each image are here:

grey : 500m grid, black: 1000m grid

A Upper Chagrito
683900,1035500

B Chamor
681400,1025300

C Vistamares
673800,1020200

D Esperanza-Chagres confluence
674200,1029700

E Upper Chico
666000,1032700

F Lower Chagres
659900,1020200

Draft presentation

Powerpoint
Openoffice

Overview of layers available at NCSU

Download:

Vector data layers in a zip file shape files for geology, land cover, stream network

Coordinates of the field sites on the streams: plain text file field sites

Original 10m resolution IFSARE-based DEM, basin/sub-basins and stream networks:
Information about these layers
DEM (47MB)|| Basin 50m|| Basin 25m|| Stream directions 50m|| Stream directions 25m|| Stream directions 10m||

Filled 10m resolution IFSARE-based DEM, basin/sub-basins and stream networks: (do not use, this is just for comparison of algorithms)
DEM (46MB)|| Basin 50m|| Basin 25m|| Stream directions 50m|| Stream directions 25m||

Selected statistics about the watershed

Basin size = 576.90 sq km or 120,000 ha

This project is supported by Army Research Office and National Research Council

Processed and visualized
by GRASS5