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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

3.18: Soil Erosion in the Little Saskatchewan River Valley

The Little Saskatchewan River occupies a large valley eroded into the ground moraine of the Minnedosa-Reston till plain.[i] Both the valley floor 1 close to the river and the valley sides 2 are covered by deciduous woodland, whereas much of the plain above the valley 3 has been cleared for agriculture. In some fields rain splash erosion has produced the characteristic light-toned hillcrests 4.

In this area, just below Minnedosa, the river meanders as it flows from northeast to southwest. Several abandoned meanders can be identified 5. Some are relatively new and still contain standing water 6, whereas others have been filled in and overgrown by trees 7. Other cutoffs are close to being created 8. Meander scars indicating previously higher river positions can be seen 9. South of the river a major river terrace has been preserved (between 10 and 11). Most of the terrace has been cleared for agriculture resulting in severe soil erosion. A series of southeast/northwest trending gullies can be seen 12, and sediment eroded from the top of the slope is deposited in fans lower down 13. Some of the fields have been left fallow, and (at 14) the farmer has started cultivating a field, either to deter soil erosion or to eliminate weeds. A north bank tributary enters the Little Saskatchewan depositing sediment near the junction of the two streams 15.

Settlement in the area is limited to two farms 16. Two railway lines cross the area 17, 18 and in the case of the more northerly line, a train can be seen on the line in the northwest corner of the photo 19. It is stationed close to an elevator that is identified by its distinctive shadow 20. A gravel road runs along the north valley side just above the floodplain 21, and other minor roads follow section lines of the DLS system.[ii] An east/west gravel road 22 is the northern boundary of township 14 that is a correction line in the system. The jog 23 is the extent of the correction at this location.

Figure 3.18: Soil Erosion in the Little Saskatchewan River Valley

Figure 3.18: Soil Erosion in the Little Saskatchewan River Valley

Figure 3.18

Vertical air photograph: A16065-32

Flight height: 9,500 feet a.s.l.; lens focal length: 152.08 mm

Date: June 10, 1958

Scale: 1:15,500 (approx.)

Location: Townships 14 and 15, Range 18 WI

Map sheets: 1: 250,000 62J Neepawa

1:50,000 62J/4 Moorepark

62J/5 Clanwilliam

Notes

[i] See Corkery, T. M. “Geology and Landforms of Manitoba” in J. Welsted, J. Everitt, and C. Stadel. eds. The Geography of Manitoba: Its Land and Its People. Winnipeg: The University of Manitoba Press, 1996. Figure 2.9, 21.

[ii] The road system in this area has changed considerably—associated with PTH 10 bypassing Minnedosa.