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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

3.45: Artesian Groundwater Effects at Catfish Creek at the South End of Lake Winnipeg

Catfish Creek 1 enters Traverse Bay 2 at the south end of Lake Winnipeg. “The stratigraphic sequence…consists of peat at the surface over relatively impermeable lacustrine silt and clay, which in turn overlie relatively permeable sandy outwash or sand till. Bedrock in the immediate area consists of relatively impermeable Precambrian rocks, such as granite and gneiss. Such stratigraphy promotes high artesian pressures in the more permeable layers. Where the surface materials are eroded away along the creek valleys, the overburden pressure is reduced and strongly artesian springs develop. The springs in turn develop craterlike depressions that appear nearly circular when flooded”[i] as along Catfish Creek 3. “The probable groundwater recharge area is located on higher ground to the southwest [4]…where outwash sand and gravel and sandy till occur in a small remnant of end moraine. On this higher ground, ponds and small lakes feed surface waters into the groundwater system. The ground water then migrates down slope toward the northeast, creating increasing artesian pressures in an aquifer that lies between layers of much less permeable material.”[ii]

 

 

A bedrock outcrop, with northwest/southeast trending joints can be seen 5. Sediment plumes can be seen in Traverse Bay 6; sediment is carried to the northwest 7 by the current of the Winnipeg River 8 entering Traverse Bay from the southeast. A small spit- like island—Jackfish Point 9—has developed on the south shore of Traverse Bay; its shape suggests transport of sediment from west to east.

PTH 11 10 follows the south shore of Traverse Bay, passing through Fort Alexander First Nation with the main settlement located at 11. Another gravel road 12 runs way along the east shore of the Bay. Some land has been cleared for agriculture on both sides of the bay 13, but back from the shore the land is mainly wooded 14.

Figure 3.45: Artesian Groundwater Effects at Catfish Creek at the South End of Lake Winnipeg

Figure 3.45: Artesian Groundwater Effects at Catfish Creek at the South End of Lake Winnipeg

Figure 3.45

Vertical air photograph: A24518-199

Flight height: 25,900 feet a.s.l.; lens focal length: 153.22 mm

Date: August 6, 1976

Scale: 1:50,000 (approx.)

Location: Township 19; Ranges 8 and 9 E

Map sheets: 1:250,000 62I Selkirk

1:50,000 62I/9 Pine Falls

Notes

[i] Mollard and Janes, op. cit., 93.

[ii] Mollard and Janes, op. cit., 93.