The Saskatchewan River (Cree: kisiskāciwani-sīpiy, "swift flowing river") is a major river in Canada, approximately 550 km (340 mi) long, flowing roughly eastward across Saskatchewan and Manitoba to empty into Lake Winnipeg. Through its tributaries the North Saskatchewan and South Saskatchewan, its watershed encompasses much of the prairie regions of central Canada, stretching westward to the Rocky Mountains in Alberta and northwestern Montana in the United States. It reaches 1,939 kilometres (1,205 mi) to its farthest headwaters on the Bow River, a tributary of the South Saskatchewan in Alberta.
North Saskatchewan river has a length of 1,287 km (800 mi), and a drainage area of 122,800 km2. At its end point at Saskatchewan River Forks it has a mean discharge of 245 m3/s. The yearly discharge at the Alberta/Saskatchewan border is more than 7 k m3.
The river begins above 1,800 metres at the toe of the Saskatchewan Glacier in the Columbia Icefield, and flows southeast throughBanff National Park alongside the Icefields Parkway. At the junction of the David Thompson Highway (Highway 11), it initially turns northeast for 10 kilometres before switching to a more direct eastern flow for about 30 km. At this point, it turns north where it eventually arrives at Abraham Lake. Bighorn Dam constricts the north end of Abraham Lake, where the North Saskatchewan emerges to track eastward to Rocky Mountain House. At Rocky Mountain House, the river abruptly turns north again for 100 km where it switches east towards Edmonton, Alberta. In Edmonton, the river passes through the centre of the city in a northeasterly direction and out towards Smoky Lake at which point it quickly changes to the southeast and then more to the east as it makes it way to the Alberta–Saskatchewan boundary.
From the border, the river flows southeast between North Battleford and Battleford and on in the direction of Saskatoon. About 40 km northwest of Saskatoon, near Langham, the river veers to the northeast where it passes through the City of Prince Albert. About 30 km downstream of Prince Albert, the North Saskatchewan River joins the South Saskatchewan River at Saskatchewan River Forks to become the Saskatchewan River. From here, the river flows east to Tobin Lake and into Manitoba, eventually emptying into Lake Winnipeg.
The river course can be divided into five distinct sections. The first, the eastern slopes of the Rocky Mountains, is the smallest area geographically, although the largest in terms of run-off and contributed water flow. The glaciers and perpetual snows of the mountain peaks feed the river year-round. Mountains, with little vegetation, experience fast-melting snow cover. The second section of the river comprises the foothills region. The terrain is hilly and rough, with a deeper and more defined valley. This area is well covered with forest and muskeg, and run-off into the river is much more constant and stable than in the mountains.
From Edmonton to the mouth of the Vermilion River, the North Saskatchewan flows through the plains-parkland divide, with occasional stretches of prairie. Here the river runs in a well-defined valley with deep cuts in the landscape. The fourth section, from the Vermilion River to Prince Albert is principally prairie with a few small stretches of timber and secondary forest cover. The valley of the river is much wider, and the river itself spreads out across shallow water and flows over many shifting sand bars. Low-lying, flat areas, border the river for much of this section. The final section of the river, from Prince Albert to the Forks, has many rapids. The valley is more shallow than the previous sections of the river, and the channel is much better defined. There is little prairie and much tree cover in this section.
The section of the North Saskatchewan river that falls within the Banff National Park boundaries has been designated a Canadian Heritage River in 1989, for its importance in the development of western Canada. The river bridges the plains–parkland divide for much of its course, acting as a natural boundary between Blackfoot and Cree First Nations people for thousands of years. With the westward expansion of the fur trade under the North West Company, the river became a natural transportation route for fur trade brigades. A number of fur trade posts were constructed on the river, including Fort Edmonton and Rocky Mountain House, the uppermost post reached by canoe navigation. After the amalgamation of the Hudson's Bay Company and the North West Company, the North Saskatchewan was a main travel route for York boats. Finally, before the arrival of the railway in western Canada, the river was plied by a number of steamboats.
Two types of Rivers that will help you understand the section of the North Saskatchewan River that passes ground zero at this Earth Cache are . . .
Meandering River
A meander, in general, is a bend in a sinuous watercourse or river. A meander is formed when the moving water in a stream erodes the outer banks and widens its valley. A stream of any volume may assume a meandering course, alternately eroding sediments from the outside of a bend and depositing them on the inside. The result is a snaking pattern as the stream meanders back and forth across its down-valley axis. When a meander gets cut off from the main stream, an oxbow lake is formed.
Meander formation is a result of natural factors and processes. The waveform configuration of a stream is constantly changing. Fluid flows around a bend in a vortex. Once a channel begins to follow a sinusoidal path, the amplitude and concavity of the loops increase dramatically due to the effect of helical flow sweeping dense eroded material towards the inside of the bend, and leaving the outside of the bend unprotected and therefore vulnerable to accelerated erosion, forming a positive feedback loop. The cross-current along the floor of the channel is part of the secondary flow and sweeps dense eroded material towards the inside of the bend. The cross-current then rises to the surface near the inside and flows towards the outside, forming the helical flow. The greater the curvature of the bend, and the faster the flow, the stronger is the cross-current and the sweeping. Due to the conservation of angular momentum the speed on the inside of the bend is faster than on the outside.
Since the flow velocity is diminished, so is the centrifugal pressure. However, the pressure of the super-elevated column prevails, developing an unbalanced gradient that moves water back across the bottom from the outside to the inside. The flow is supplied by a counter-flow across the surface from the inside to the outside. This entire situation is very similar to the Tea leaf paradox. This secondary flow carries sediment from the outside of the bend to the inside making the river more meandering.
Braided River
A Braided river is one of a number of channel types and has a channel that consists of a network of small channels separated by small and often temporary islands called braid bars or, in British usage, aits or eyots. Braided streams occur in rivers with high slope and/or large sediment load. Braided channels are also typical of environments that dramatically decrease channel depth, and consequently channel velocity, such as river deltas, alluvial fans, and peneplains.
Braided rivers, as distinct from meandering rivers, occur when a threshold level of sediment load or slope is reached. Geologically speaking, an increase in sediment load will over time increase the slope of the river, so these two conditions can be considered synonymous; and, consequently, a variation of slope can model a variation in sediment load. A threshold slope was experimentally determined to be 0.016 (ft/ft) for a 0.15 cu ft/s (0.0042 m3/s) stream with poorly sorted coarse sand. Any slope over this threshold created a braided stream, while any slope under the threshold created a meandering stream or— for very low slopes—a straight channel. So the main controlling factor on river development is the amount of sediment that the river carries; once a given system crosses a threshold value for sediment load, it will convert from a meandering system to a braided system. Also important to channel development is the proportion of suspended load sediment to bed load. An increase in suspended sediment allowed for the deposition of fine erosion-resistant material on the inside of a curve, which accentuated the curve and in some instances caused a river to shift from a braided to a meandering profile. The channels and braid bars are usually highly mobile, with the river layout often changing significantly during flood events. Channels move sideways via differential velocity: On the outside of a curve, deeper, swift water picks up sediment (usually gravel or larger stones), which is re-deposited in slow-moving water on the inside of a bend.
The braided channels may flow within an area defined by relatively stable banks or may occupy an entire valley floor. Conditions which promote braided channel formation are . . .
1 => an abundant supply of sediment
2 => high stream gradient
3 => rapid and frequent variations in water discharge
4 => erodible banks
5 => a steep channel gradient
This cache is easily found North Bound to North Battleford as there is a “Point of Interest” sign approx. 1 km prior to the turn off to ground zero. It is also accessible heading to southbound to Saskatoon, but PLEASE be careful when crossing the highway. To register this find, you need to answer the following questions. Do not post your answers with your log . . . please email them to me directly:
1. What is the name of the land formation in the middle of the River when facing due North from ground Zero?
2. Once at ground zero, you will find that this section of the North Saskatchewan River is a Braided river, which mean that there is heavy loads of sediment present. From the information above and from seeing the River in person . . . Where is the sediment coming from? And why is it settling in this “4th section” of the North Saskatchewan river?
3. What would be formed if the meander is cut off from the main stream? What would be the direct adverse impact to the local area?
4. What is the reference to the Saskatchewan River in the The Arrogant Worms' song "The Last Saskatchewan Pirate"? (Completely optional, but we all know the song! Google or the sources below will give you the answer!).
5. Please take a photo of the North Saskatchewan River in all its glory. It would be awesome if you were in the picture, but that is not necessary. (This step is completely optional)
Please note that this is an Earthcache, which means there is not a physical cache at ground zero. For more information on Earch caches, please visit www.geocaching.com or www.earthcache.org.
Sources:
http://en.wikipedia.org/wiki/North_Saskatchewan_River
http://en.wikipedia.org/wiki/Saskatchewan_River
http://en.wikipedia.org/wiki/Braided_river
http://en.wikipedia.org/wiki/Meander