Chapter 19: Legal Issues and Law Enforcement
Vertical air photos record situations that exist at a specific time and are particularly useful in recording changes if a sequence of photos of the same area exists. Property boundaries are difficult to define if they fall along a naturally changing feature such as a river channel. Three examples illustrate the legal problems that can arise.
Rivers have traditionally been used as boundaries between various administrative units: municipalities, counties, provinces, states, and even countries. However, they are unsatisfactory administrative boundaries because they change position over time resulting in ownership disputes.
19.2: Meanders on the Assiniboine River Near the Junction with Birdtail Creek, 1956 Photo
Abandonment is still imminent at 7 but at 8 breakthrough has recently occurred; water now flows in a direct route across the meander neck as well as round the meander. This photo was taken from a greater height than figure 19.1 and consequently covers a larger area at a smaller scale. A cut off appears imminent 9, and existing cut offs can be seen to the north (10,11,and 12) and to the south 13. On this photo there is a very clear distinction between the dark tones of the cut offs and the light tone of the sediment-laden main channel.
Figure 19.2: Meanders on the Assiniboine River Near the Junction with Birdtail Creek, 1956 Photo
Vertical air photograph: A15528-108
Flight height: 20,000 feet a.s.l.; lens focal length: 6 inches
Date: October 17, 1956
Scale: 1:37,400 (approx.)
Location: Townships 15 and 16; Ranges 27 and 28WI
Map sheets: 1:250,000 62K Riding Mountain
1:50,000 62K/6 Birtle