II.2.3 - River Description File (columbia.desc)

File Structure

The columbia.desc file is an ASCII file that can be edited by the user and contains the following information:

• names of species
• names and locations of release sites on river
• names of dams, positions on the river and basic dimensions
• names of river segments, latitude, longitude, widths and depths.

The river description file contains information specifying the physical characteristics of the river. The file must follow rules for construction of a river map. Rules on ordering of tokens (or keywords) include:

• Species tokens must appear first, before river description tokens.
• Release sites typically appear next, although they may appear anywhere in the file except within a river stem description (bounded by the tokens "river" and "end").
• The first river specified is the main stem, and the first river segment specified is the river mouth. Remaining segments must appear in order (moving upstream) toward the headwater. The first latitude and longitude coordinate (latlon) point of each successive segment must match the last latlon of the preceding segment. Latlons within a segment should appear in order.
• Other complete river branch descriptions may appear in any order, and each will be attached to the appropriate existing river branch by comparing latlon points.
• The first segment specified in any river branch is taken to be the confluence point. This segment must be a reach. The first latlon in this segment must match the last latlon of some existing reach segment on another branch.
• Dam segments must have exactly one latlon point, matching the last latlon of the previous segment. No two dams may be adjacent.
• If a dam is identified as a "storage basin" then it must be the last (furthest upstream) segment on that river branch.

Fig. 5 Portion of the columbia.desc file

Default columbia.desc File

The default columbia.desc file contains an abbreviated description of the river system with about thirty fish release points and major dams (Fig. 6). Some rivers are not represented in this map (e.g. Imnaha, Grand Ronde).

Fig. 6 Default Columbia River description map, showing release sites (red and green fish), dams, and rivers.