Hydrographic Analysis

This map below is an effort to map a watershed for the Knik River in Southcentral Alaska. I downloaded a DEM from USGS, and used the following tools to create the map below.

Fill

Flow accumulation

Flow direction

Hillshade

Slope

Aspect

Snap Pour Point

Watershed Delineation Tool.


The goal was to create a stream that marked all the streams and substreams with a marker delineating the strength of the stream. This was not to be. I reclassified the stream into two classes of NODATA below 500 cells, and greater than 500 cells. It gave me the results below with the single line. None of my other maps showed this. The river also ended rather abruptly. It took me a while, but then I realized that I was bumping up against the Knik Glacier---the source of the river itself. But the substreams are missing---how did this occur? (Hint, I fixed this later, and the results are in the map on the bottom to the left.


High resolution PDF:

Knik Watershed Extent II (1).pdf

High resolution pdf