boundary

Hydrologic Unit Code (HUC) Hierarchy Table

Mystified by the often-confusing terminology associated with water drainage naming and numbering?

This table relates well to the official NHD/USGS system (source: Wikipedia 2015Feb05).

The GIS layer Hydrologic Units includes Level 3 (3rd-code/6-digit) through Level 6 (6th-code/12-digit) polygons.

 

These images should help clarify, beginning at the HUC3 level,

Lower Snake River Basin selected:

Lower Snake River Basin description

 

Zoom in to HUC4 with Imnaha River (Oregon) Subbasin selected:

 

Zoom in to HUC5 with Upper Imnaha River Watershed selected:

 

Zoom to HUC6, South Fork Imnaha River Subwatershed selected:

 

How to Load a Boundary (Track) File into a GPS Unit

 

Let’s say you would like to upload Game Management Unit 1 to your GPS. 

1) Download the Game Management Units KML from the IFWIS Open Data page, https://fishandgame.idaho.gov/ifwis/portal/opendata.

2) Open the KML in Google Earth. Right-click “1” in the gmu features list. Select “Save Place As…”

3) Save the feature as a KML (not a KMZ).

4) Convert the KML to a GPX file.  There are many open-source software options.  I like KML2GPX.exe (download from https://groups.google.com/forum/?fromgroups=#!msg/kml-support-getting-started/5K7vcIGUz6s/_EvtN-YqXuwJ) and GPSBabel (download from http://www.gpsbabel.org/).

5) Upload the GPX file as a track to your GPS.  NOTE: for those GPS units with smaller data storage space or without a data storage card the track may be too large to upload without simplifying.  Using GPSBabel, you can apply a “Filter” to the Routes & Tracks to simplify the boundary.  For units such as the etrex Vista Cx, I know that the track point upload limit is 500 (otherwise it will give you a message that says “track truncated”. The Minnesota DNRGPS Application also works well for uploading data but I have not found a way to simplify the track using this software (http://www.dnr.state.mn.us/mis/gis/DNRGPS/DNRGPS.html). 

There are many different tactics for completing this process but these are the steps that have given me the least amounts of difficulties for a number of different Garmin GPS units.  These steps have not been tested on Magellan, Lowrance, TomTom, etc.

Do you have another method that works better for you?  Please share in the comment below!

Game Management Units

24k version of Idaho Fish & Game's (IDFG) Game Management Units (GMUs). This file was produced by IDFG from the GMU legal descriptions available in the back of the published regulations.

Reflects IDFG Commission Action GMU boundary description changes in August 2011.

Administrative Regions

The seven administrative regions of Idaho Fish and Game: Panhandle, Clearwater, Southwest, Magic Valley, Southeast, Upper Snake and Salmon.