Heading south toward Mainprize Regional Park we will pass widely separated 'giant' mounds (up to 15 m3 in volume) constructed by an extinct gopher colony (Fig. 25). We are led to suspect their extraordinary mound-building behavior was somehow related to past climatic and geologic conditions, and that some of their genes may reside in their descendents, our modern

subterranean pocket gophers, Thomomys Talpoides Talpoides. These 10-cm-long critters spend virtuallyall their lives underground, drawing herbaceous plants into their shallow burrows,where they remove the surrounding dirt by closing their lips behind long protruding teeth (Fig. 26).

One might logically think such knowledge has no practical value. Yet engineers with SaskTel and SaskPower--burying long and costly fibre optic cableand installing province-wide plastic gas pipelines into farmsteads, respectively--learned to their dismay that these little beasts looked on fibre optic cable and plastic pipe as a sustenance of choice. Such a serious situation called for an area-wide search for their presence in the Saskatchewan landscape, a quest necessarily guided by some knowledge of their behavior and energetics,particularly their preferred geologic and ecologic niches.

Approaching Mainprize Park we discern a landscape born when glacial Lake Regina waters drained down the Souris Spillway. It has beenestimated that the rate of meltwater flow reached 100,000 m³/s--over 8.5 billion cubic metres a day! An obvious visible sign of this catastrophic flood is the heavy concentration of huge glacial boulders washed out of bouldery till and onto the Souris Spillway floor. Although this event is said to have taken place approximately 12,000 years ago, it created horrendous problems during construction of the 18-hole Mainprize golf course and nearby marina, summer cottages, year-round homes, and related infrastructure development (Fig. 27). Because a number of people chose

to build homes and boat-launching docks close to the reservoir shoreline, where water levels fluctuate several metres during the year, it was important to estimate the long-term rate of future shore erosion, in m/yr, taking into account shore-zone wave energy, shore-zone geometry in plan and profile, and the physical composition and erodibility of shore-zone soil material (Fig. 28).

Q. Fig. 25 - In trying to discover the most likely landscape locations of the modern Saskatchewan pocket gopher, which has demonstrated a predilection for fibre optic cables and plastic pipelines, it was felt that answers to questions on the behaviour of their ancestors might provide these helpful clues:

• Why did they show a distinct preference for a near-surface two-layer stratigraphic sequence?
• Why did they favor thin calcareous silty surficial soil over deep highly plastic clay or gravelly sand?
• Why did they choose slightly higher ground sites for mound-building?
• Why did they construct such high mounds?
• Why did they frequently space their mounds at regular intervals?

Q. Fig. 27 - How would you go about estimating the maximum discharge of the catastrophic glacial meltwater flood that drained Lake Regina and poured down the Souris Spillway around Mainprize Park?