Acquired aerial photography (1:5000 to 1:60 000 scale).
Performed aerotriangulation of photography, geo-referencing all photogrammetric controls to true ground coordinates.
Collected vector digital data using analogue plotters (Wild A10 - A8 - B8S). Vector data were three dimensional (x,y,z) and geo-referenced to UTM coordinates. The output format was DXF.
Performed cursory checks of digital data (removal of pseudo nodes, creation of polygons, etc.).
Built lines and points then copied attribute information from the ACODE and XCODE tables into the arc and point attribute tables (AAT and PAT). Dropped five attribute fields from the resulting attribute tables.
Selected arcs representing water polygons based on the dxf-layer attribute. Put the arcs for each water polygon category to respective ArcInfo coverages.
Built water polygons, created error files if dangles or intersections were present, then cleaned coverages with fuzzy and dangle tolerances of 0.0001.
Manually edited coverages to eliminate dangles.
Joined all water polygon layers into one coverage, cleaned with tolerances of 0.01, and checked for label errors. Performed manual edits to correct label errors.
Appended mapsheet water polygon coverages into a Manitoba-wide coverage and cleaned with fuzzy and dangle tolerances of 0.01. Unsplit arcs based on the dxf-layer attribute code. Performed edits to ensure good edgematching. Eliminated sliver polygons created by overlapping polygons along mapsheet boundaries. Checked for and corrected label errors.
Visually checked polygons with an area of less than 15 square-meters. If polygons were slivers, performed manual edits to eliminate them.
Named water bodies by referring to 1:50 000 paper maps and 1:20 000 drain coverages.
Classified water bodies by feature description and size into three categories: Major, Medium, and Small. Major water bodies included water bodies larger than 500 000 square-meters and lakes and rivers that overlapped with a 1:1 000 000-scale hydrography layer. Medium water bodies included tributaries of major water bodies and lakes, rivers and marshes measuring 10 000 to 500 000 square-meters. Small water bodies included tributaries of medium water bodies, lakes, rivers, and marshes smaller than 10 000 square-meters, and wharfs. Classed perennial rivers one by one based on adjoining rivers. Assigned islands, dugouts, dams, spillways, and rapids the same class as their associated water bodies.