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Rocky Mountain Trench

Rocky Mountain Trench

Overview
The Rocky Mountain Trench, or the Trench or The Valley of a Thousand Peaks, is a large valley in the northern part of the Rocky Mountains
Rocky Mountains
The Rocky Mountains are a major mountain range in western North America. The Rocky Mountains stretch more than from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States...

. It is both visually and cartographically a striking physiographic feature extending approximately 1600 km (994.2 mi) from Flathead Lake
Flathead Lake
Flathead Lake is the largest natural freshwater lake in the western part of the contiguous United States. With a surface area of between and , it is slightly larger than Lake Tahoe. The lake is a remnant of the ancient inland sea, Lake Missoula of the era of the last interglacial. Flathead Lake...

, Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

, to the Liard River
Liard River
The Liard River flows through Yukon, British Columbia and the Northwest Territories, Canada. Rising in the Saint Cyr Range of the Pelly Mountains in southeastern Yukon, it flows southeast through British Columbia, marking the northern end of the Rocky Mountains and then curving northeast back...

, just south of the British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...

-Yukon
Yukon
Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....

 border near Watson Lake, Yukon
Watson Lake, Yukon
Watson Lake is a town at historical mile 635 on the Alaska Highway in the southeastern Yukon close to the British Columbia border. Population in December 2004 was 1,547 ....

. The trench bottom is 3-to-16 km (2–10 miles) wide and ranges from 600–to-900 metres (2,000–3,000 feet) above sea level.
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Encyclopedia
The Rocky Mountain Trench, or the Trench or The Valley of a Thousand Peaks, is a large valley in the northern part of the Rocky Mountains
Rocky Mountains
The Rocky Mountains are a major mountain range in western North America. The Rocky Mountains stretch more than from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States...

. It is both visually and cartographically a striking physiographic feature extending approximately 1600 km (994.2 mi) from Flathead Lake
Flathead Lake
Flathead Lake is the largest natural freshwater lake in the western part of the contiguous United States. With a surface area of between and , it is slightly larger than Lake Tahoe. The lake is a remnant of the ancient inland sea, Lake Missoula of the era of the last interglacial. Flathead Lake...

, Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

, to the Liard River
Liard River
The Liard River flows through Yukon, British Columbia and the Northwest Territories, Canada. Rising in the Saint Cyr Range of the Pelly Mountains in southeastern Yukon, it flows southeast through British Columbia, marking the northern end of the Rocky Mountains and then curving northeast back...

, just south of the British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...

-Yukon
Yukon
Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....

 border near Watson Lake, Yukon
Watson Lake, Yukon
Watson Lake is a town at historical mile 635 on the Alaska Highway in the southeastern Yukon close to the British Columbia border. Population in December 2004 was 1,547 ....

. The trench bottom is 3-to-16 km (2–10 miles) wide and ranges from 600–to-900 metres (2,000–3,000 feet) above sea level. The general orientation of the Trench is an almost uniform 150/330 degree geographic north vector which has also become convenient for north/south aviators.

Although some of its topography
Topography
Topography is the study of Earth's surface shape and features or those ofplanets, moons, and asteroids...

 has been carved into glacial valley
U-shaped valley
A U-shaped valley also known as a glacial trough is one formed by the process of glaciation. It has a characteristic U-shape, with steep, straight sides, and a flat bottom. Glaciated valleys are formed when a glacier travels across and down a slope, carving the valley by the action of scouring...

s, it is primarily a by-product of faulting
Geologic fault
In geology, a fault is a planar fracture or discontinuity in a volume of rock, across which there has been significant displacement along the fractures as a result of earth movement. Large faults within the Earth's crust result from the action of tectonic forces...

. The Trench separates the Rocky Mountains
Rocky Mountains
The Rocky Mountains are a major mountain range in western North America. The Rocky Mountains stretch more than from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States...

 on its east from the Columbia Mountains
Columbia Mountains
The Columbia Mountains are a group of mountain ranges located in southeastern British Columbia, and partially in Montana, Idaho and Washington. The mountain range covers 135,952 km² . The range is bounded by the Rocky Mountain Trench on the east, and the Kootenay River on the south; their...

 and the Cassiar Mountains
Cassiar Mountains
The Cassiar Mountains are the most northerly group of the Northern Interior Mountains in the Canadian province of British Columbia and the Yukon Territory. They lie north and west of the Omineca Mountains, west of the northernmost Rockies and the Rocky Mountain Trench, north of the Hazelton...

 on its west. It also skirts part of the McGregor Plateau
McGregor Plateau
The McGregor Plateau is a sub-plateau of the Fraser Plateau, the northernmost major subdivision of the Interior Plateau spanning the inland regions of the Pacific Northwest...

 area of the Nechako Plateau
Nechako Plateau
The Nechako Plateau is the northernmost subdivision of the Interior Plateau, one of the main geographic regions of the Canadian province of British Columbia...

 sub-area of the Interior Plateau
Interior Plateau
The Interior Plateau comprises a large region of central British Columbia, and lies between the Cariboo and Monashee Mountains on the east, and the Hazelton Mountains, Coast Mountains and Cascade Range on the west. The continuation of the plateau into the United States is known there as the...

 of British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...

. It is up to 25  km wide, if measured peak-to-peak, and varies in valley relief, but is clearly visible from the air, satellite/remote sensing and is commonly discernible to those ascending any of the mountains or ridges lining it.

It is drained by four major river basins: the Columbia
Columbia River
The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...

, Fraser
Fraser River
The Fraser River is the longest river within British Columbia, Canada, rising at Fraser Pass near Mount Robson in the Rocky Mountains and flowing for , into the Strait of Georgia at the city of Vancouver. It is the tenth longest river in Canada...

, Peace
Peace River (Canada)
The Peace River is a river in Canada that originates in the Rocky Mountains of northern British Columbia and flows to the northeast through northern Alberta. The Peace River flows into the Slave River, a tributary of the Mackenzie River. The Mackenzie is the 12th longest river in the world,...

 and Liard
Liard River
The Liard River flows through Yukon, British Columbia and the Northwest Territories, Canada. Rising in the Saint Cyr Range of the Pelly Mountains in southeastern Yukon, it flows southeast through British Columbia, marking the northern end of the Rocky Mountains and then curving northeast back...

. Two reservoirs of the Columbia River Treaty
Columbia River Treaty
The Columbia River Treaty is an agreement between Canada and the United States of America on the development and operation of dams in the upper Columbia River basin for power and flood control benefits in both countries. For more information about the Columbia River Treaty, visit Columbia Basin...

 fill much of its length today - Lake Koocanusa
Lake Koocanusa
Lake Koocanusa is a reservoir in British Columbia and Montana formed by the damming of the Kootenai River by the Libby Dam in 1975....

 and Lake Kinbasket. A further British Columbia power initiative created Lake Williston
Williston Lake
Williston Lake is a reservoir created by the W. A. C. Bennett Dam and is located in the Northern Interior of British Columbia, Canada.-Geography:...

. Rivers that follow the Trench, at least in part, are the Kootenay River
Kootenay River
The Kootenay is a major river in southeastern British Columbia, Canada and the northern part of the U.S. states of Montana and Idaho. It is one of the uppermost major tributaries of the Columbia River, which is the largest North American river that empties into the Pacific Ocean...

, the Columbia River
Columbia River
The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...

, Canoe River
Canoe River (British Columbia)
Canoe River is a tributary of the Columbia River in British Columbia, Canada. Its lower reach is flooded by Mica Dam. The lower Canoe River is called Canoe Reach, part of the Mica Dam's reservoir, Kinbasket Lake.-Course:...

, the Flathead River
Flathead River
The Flathead River, in the northwestern part of the U.S. state of Montana, originates in the Rocky Mountains near Glacier National Park and flows southwest into Flathead Lake, then after a journey of , empties into the Clark Fork. The river is part of the Columbia River drainage basin, as the Clark...

, Fraser River, Parsnip River
Parsnip River
The Parsnip River is a 240 km long river in central British Columbia, Canada. It flows generally north-westward from the Parsnip Glacier in the Hart Ranges to the Parsnip Reach of Williston Lake, formed by the impounding of the waters of the Peace River by the W.A.C. Bennett Dam in 1968...

, Finlay River
Finlay River
The Finlay River is a 402 km long river in north-central British Columbia flowing north and thence south from Thutade Lake in the Omineca Mountains to Williston Lake, the impounded waters of the Peace River formed by the completion of the W.A.C. Bennett Dam in 1968. Prior to this, the Finlay...

, Fox River, and the Kechika River
Kechika River
The Kechika River also historically known as Black's River, is a tributary of the Liard River, located in northern British Columbia, Canada. The river rises at the Sifton Pass and flows northwest and then east 230 kilometres to join with the Liard River near Fireside, British Columbia...

. The Kechika is part of the Liard River system, and the Fox, Parsnip and Finlay Rivers and part of the Peace River system. The Canoe River is a short tributary of the Columbia system, draining into Kinbasket Lake
Kinbasket Lake
Kinbasket Lake is a reservoir on the Columbia River in southeast British Columbia, north of the city of Revelstoke and the town of Golden. The reservoir was created by the construction of the Mica Dam. The lake includes two reaches, Columbia Reach and Canoe Reach , referring to the river valleys...

, a reservoir on the Columbia River. The Kootenai River, however, does not fully follow the Trench but exits Canada southwest via Lake Koocanusa reservoir to the Libby Dam
Libby Dam
Libby Dam is a dam on the Kootenai River in the U.S. state of Montana.Dedicated on August 24, 1975, Libby Dam spans the Kootenai River upstream from the town of Libby, Montana. Libby Dam is tall and long. Lake Koocanusa is the name of the reservoir behind the dam; it extends upriver from...

. The Kootenay (Canadian spelling) River is a tributary of the Columbia
Columbia River
The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...

, joining the Columbia at Castlegar, BC
Castlegar, British Columbia
Castlegar is the second largest city in the West Kootenay region of British Columbia, Canada. It is located within the Selkirk Mountains at the confluence of the Kootenay and Columbia Rivers. It is a regional trade and transportation centre, with a local economy fueled by forestry, mining and tourism...

 after an incongruous meander through the USA under the Kootenai River(US spelling).

For convenience the Rocky Mountain Trench may be divided into two sections - being the Northern Rocky Mountain Trench and Southern Rocky Mountain Trench. The dividing point reflects the separation of north and easterly flows to the Arctic Ocean versus south and westerly flows to the Pacific Ocean. A break in the valley system at ~54°N near Prince George
Prince George, British Columbia
Prince George, with a population of 71,030 , is the largest city in northern British Columbia, Canada, and is known as "BC's Northern Capital"...

, British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...

 may be used for this purpose. The northern portion of the Trench is dominated by strike-slip faulting while the southern part of the Trench was created by normal faults. Despite differences in timing and faulting styles of the northern and southern portions, they were aligned with each other because faulting for both was controlled by a pre-existing, west-facing, deep basement
Basement Rock
Basement or Basement Rock music was a sub-genre coined in 2006 in an article by music magazine TGR. This was first in relation to the existence of underground record label Criminal Records but more for the independent bands they represent. The roots of the sub-genre are noted to be as far back as...

 ramp with over 10 km of vertical offset.

Northern Rocky Mountain Trench


The Northern Rocky Mountain Trench is closely aligned with the Tintina Trench
Tintina Trench
The Tintina Trench is a large valley extending through Yukon, Canada. It is the northern extension of the Northern Rocky Mountain Trench in British Columbia and it has its origin from the Tintina Fault. Much of the valley serves as the path through which flows the Pelly River, a tributary of the...

 near the British Columbia-Yukon border at 60 degrees north latitude, and the two trenches could arguably be classified as one and the same - or 'extensions' of each other. The Tintina Trench extends further north-westward through the Yukon
Yukon
Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....

 into Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

. The visible expression of the two trenches is lost where they plunge under the boreal forests of the Liard Plain proximate to the small communities of Watson Lake, Yukon and Lower Post, BC. The highest point in the northern Trench is Sifton Pass at an elevation of about 1010 metres near the bend of Scarcity Creek.

Geology


Right-lateral strike-slip movement of the Tintina Fault
Tintina Fault
The Tintina Fault is a large strike-slip fault in western North America, extending from northwestern British Columbia, Canada to the U.S. state of central Alaska. It represents the northern extension of the Rocky Mountain Fault in the northern United States....

 on the Tintina-Northern Rocky Mountain Trench may have begun during the middle Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to  Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...

. The fastest rates of slip probably occurred during two pulses in the middle Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 and early Cenozoic
Cenozoic
The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...

, respectively, with the latter probably occurring during the Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

. Between 750 km to > 900 km of total right-lateral movement has occurred, of which 450 km of offset has occurred since the mid-Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

. The end result is that terrains to the west of the fault system have moved toward the north. In the context of plate tectonics
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...

, strike-slip movement of the Tintina Fault on the Tintina-Northern Rocky Mountain Trench is also related to strike-slip movement along the San Andreas Fault
San Andreas Fault
The San Andreas Fault is a continental strike-slip fault that runs a length of roughly through California in the United States. The fault's motion is right-lateral strike-slip...

, the extension of the Basin and Range Province, and other extensional
Extensional fault
An extensional fault is a fault that vertically thins and horizontally extends portions of the Earth's crust and/or lithosphere. In most cases such a fault is also a normal fault, but may be rotated to have a shallower geometry normally associated with a thrust fault...

 or strike-slip fault systems in western North America. The Tintina Fault is one of the two major fault zones paralleling the Northern Cordilleran Volcanic Province
Northern Cordilleran volcanic province
The Northern Cordilleran Volcanic Province , formerly known as the Stikine Volcanic Belt, is a geologic province defined by the occurrence of Miocene to Holocene volcanoes in the Pacific Northwest of North America...

, the other being the Denali Fault
Denali Fault
The Denali Fault is a major intracontinental dextral strike-slip fault in western North America, extending from northwestern British Columbia, Canada to the U.S. state of central Alaska. It was the main fault along which the 2002 Denali earthquake occurred, which was measured as a magnitude of 7.9...

 in the Yukon
Yukon
Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....

, the U.S. state
U.S. state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

 and along the British Columbia Coast
British Columbia Coast
The British Columbia Coast or BC Coast is Canada's western continental coastline on the Pacific Ocean. The usage is synonymous with the term West Coast of Canada....

.

Settlements


The Northern Trench hosts only a few present day communities; From south to north they are:
  • Mackenzie, British Columbia
    Mackenzie, British Columbia
    Mackenzie is a District Municipality within the Fraser-Fort George Regional District in central British Columbia, Canada. The settlement is located at the south end of Williston Lake. The townsite, established by Alexandra Forest Industries, was named for Sir Alexander MacKenzie . Mackenzie's two...

  • Ingenika
  • Tsay Keh Dene First Nation
    Tsay Keh Dene First Nation
    The Tsay Keh Dene First Nation is one of the Sekani bands of the Northern Interior of British Columbia. While their offices are located in the City of Prince George, their territories, settlements, and Indian Reserves are all to the north, in the area of Lake Williston.-Indian Reserves and...

  • Ware the home of the Kwadacha First Nation.http://www.kwadacha.com/nation
  • Lower Post
    Lower Post, British Columbia
    Lower Post is an aboriginal community in northwestern British Columbia, Canada, located on Highway 97, the Alaska Highway, approximately 15 miles southeast of Watson Lake, Yukon. Its historical mile designation is Mile 620...

     the home of the Day Lu or Liard First Nation
  • The former Hudson's Bay Company (HBC) outposts of Finlay Forks and Fort Graham now lie beneath the waters of Williston Reservoir.

History and accessibility


First Nations have traditionally always travelled the northern Trench. There are several epic post-European contact travels up the northern Trench - often of legendary proportion. But the Trench here remains mostly wild, and the northern 300 km is essentially unroaded despite a few cat trails for fire, outfitters, or logging. This wildland is a credit to several turns of fate and arguably strategic administrative decisions since 1824. The most natural of all land transportation corridors in northern British Columbia has been left in a wild state. On many government maps produced since 1897, indications of a passable trail have been published. However with changes in beaver dams, forest fires, despite maintenance by guide-outfitters, the trail from Fox Lake north is often hard to find, or obliterated to all but indigenous and experienced Kaska natives.

The northern trench is however an undisputed aviation route today.

The northern trench from the Highway 97 bridge on the Parsnip River has routes on both sides of Williston Reservoir to Fort Ware. The route up the east side cannot be followed due to the Peace Reach of the reservoir. The road traveler will use the gravel road up the west side of the Reservoir to Ware. Beyond that point the northbound traveller will only find a narrow cat road for a few kilometres.

The Kaska Dena culture of Fort Ware and Lower Post refer to their ancestral use of the 300 km natural route as The Trail of The Ancient Ones. They also call it the Davie Trail honoring David Braconnier, the founding chief of the community at Ware (Fort Ware - originally called Kwadacha which the HBC named Whitewater Post)

1797 - John Finlay records the forks of the Finlay and Parsnip Rivers and ventures part way up each river. The Finlay River later comes to bear his name.

1823 to 1825 - Samuel Black
Samuel Black
Samuel Black was a Canadian fur trader and explorer noted for his exploration of the Finlay River and its tributaries in present-day north-central British Columbia, which helped to open up the Muskwa, Omineca, and Stikine areas to the fur trade; as well for his role as Chief factor of the Hudson's...

 was sent by the HBC north through Finlay Forks to The Fox River (Kwadacha) and returned later that season. He narrowly missed being the first white person to go all the way up the Northern Trench to the Liard River but chose not to listen to his guide - heading north westward seeking the source of the Finlay River
Finlay River
The Finlay River is a 402 km long river in north-central British Columbia flowing north and thence south from Thutade Lake in the Omineca Mountains to Williston Lake, the impounded waters of the Peace River formed by the completion of the W.A.C. Bennett Dam in 1968. Prior to this, the Finlay...

 instead. He travels far enough NW to discover the headwaters of another Trench tributary - The Turnagain River. Natives there find a marker left by Black and report it to historic Fort Halkett on the Liard River. http://www.bcarchives.gov.bc.ca/cgi-bin/text2html/finding/government/.ms_cat/MS-0619.txt?MS-0619

1831 - John Macleod of the HBC records the mouth of the Kechika River emptying out of the northern end of the Trench into the Liard near the BC-Yukon border.

1872 - Capt. William F. Butler ascends part of the Finlay River and records both the Fox River and Fox Lake to the north (Ft. Ware / Kwadacha was not yet established.)

1897 to 1898 – The Canadian government sends a police patrol under Inspector Moodie to map a possible supply route from the Peace River to the Yukon - specifically Dawson City. The patrol, assumed to have perished, eventually arrived at Fort Sekirk. They proved the viability of the route and produced a surviving map of it. (Yukon Archives)

1898 – McGregor's book The Klondike Rush Though Edmonton summarizes various sources (papers) saying up to 45 parties were reported along the route from Fox River to Sylvestre's Landing. There was also a reported drive of cattle on this route (echoed in Moodie's reports and in Kaska oral history.)

1906 – A North West Mounted Police patrol under field supervision of Inspector Constantine began the construction of the Police Trail westward from Hudson Hope and then northward up the Northern Trench from HBC's post at Fort Graham.

1907 - British Columbia Premier R. McBride intervened and asked Canada to direct the police resources to connect with the more westerly Telegraph Trail route. Under protest, the NWMP field team did so. That trail was soon abandoned due to its non-viable character. The political route departure from Fort Graham westward added 400 rugged snowy kilometres to the total distance without going any favorable ground or measurable distance closer to the north. The Davie Trail is noted to be excellent for wintering horse due to low snow accumulations.

1912 - British Columbia Magazine - prospector Bower reports Sifton Pass as the most eventual and most practicable for a railway form the Fraser River to the Yukon.

1914 - Premier McBride advocates a railway on Insp. Moodie's route according to B. Kenelly in a pamphlet 'The British Columbia Peace. Fort St John' 1936.

1926 - Whitewater Post is established by HBC. Whitewater is the translation of Kwadacha, a nearby river.

1930 to 1931 - British Columbia Department of Public Works investigates a road route over Sifton Pass.

1934 - Charles Bedaux
Charles Bedaux
Charles Eugène Bedaux was one of the most colorful millionaires of the early twentieth century. Friends with British royalty and Nazis alike, he amassed a fortune expanding on the Taylorism style of scientific management and was a big game hunter and explorer.-Early years:Charles Bedaux was born...

, a noted international workplace management consultant (time and motion studies) leads and finances the Bedaux Expedition
Bedaux Expedition
The Bedaux Expedition also named the Bedaux Canadian Subarctic Expedition was an attempt by eccentric French millionaire, Charles Eugène Bedaux to cross the British Columbia wilderness, while making a movie, testing Citroën half-tracks and generating publicity for himself...

 - formally known as the Bedaux Canadian Subarctic Expedition. While his advance scouts arrive at McDame Post near Good Hope Lake, the leader and entourage abandon their mission at Driftpile Creek due to fatigue, lack of horse feed, and impending winter. The controversial adventure is the subject of a 1995 Bedaux film biography titled Champagne Safari.

1942 - February a final decision was reached regarding the A, B, and C routes for a northern Highway. It will connect the North West Staging Route airfields and bypass the Northern Trench for the joint Canada-Alaska Highway Alcan Highway, alternately Alaska Highway
Alaska Highway
The Alaska Highway was constructed during World War II for the purpose of connecting the contiguous U.S. to Alaska through Canada. It begins at the junction with several Canadian highways in Dawson Creek, British Columbia and runs to Delta Junction, Alaska, via Whitehorse, Yukon...

. The three routes had been the subject of considerable economic competition between governments and communities since the Klondike Gold Rush. The A route was a Stikine option similar to Highway 37 of today. The B route favors the Trench option. The C route following the airfields east of the Rocky Mountains and then crossing to the west near the Liard River is the chosen route.

1942 - March 28 the American government initiates a highly secret survey. It was undertaken for the purpose of assessing a military railway link up the Northern Rocky Mountain Trench. It was completed on Sept 28. Nov 15 US General Somervell declines to proceed with a military railway. Canada's Major Charles presents drawings for the Northern Trench portion of a railway from Ware to Lower Post of 218.5 miles, $112,000,000 cost, with 17,000 personnel over 400 days. Of the 1217 total miles of proposed railway to Alaska, 530 are on Canadian soil and lie within the Northern Rocky Mountain Trench or the Tintina Trench.

1949 - US Congress Public Law 391 authorises a location survey for a railway from Prince George to Fairbanks. Prince George Board of Trade advocates the Trench route - the B route.

1950 - October, Canadian Transport Minister Lionel Chevrier advocates the 1942 route in a secret document to Federal Cabinet. A budget of $750,000,000 is presented.

1953 - Whitewater Post or Kwadacha of the HBC closes. Today the Kaska Dena Community of Fort Ware (Ware) remains as a full time settlement.

1957 - Swedish industrial savant Axel Wenner-Gren
Axel Wenner-Gren
Axel Lennart Wenner-Gren was a Swedish entrepreneur and one of the wealthiest men in the world during the 1930s....

 advocates resource mega-developments for the Peace River area. Among his proposals he envisions a monorail up the Northern Trench. Some area proposals came to partial fruition but the monorail did not.

1960 to 1967 - The Government of BC declines the Northern Trench as their strategic railway choice, favoring instead a route to the west similar to the telegraph route. Part of the reason is that the Lower Finlay
Finlay River
The Finlay River is a 402 km long river in north-central British Columbia flowing north and thence south from Thutade Lake in the Omineca Mountains to Williston Lake, the impounded waters of the Peace River formed by the completion of the W.A.C. Bennett Dam in 1968. Prior to this, the Finlay...

 and Parsnip River
Parsnip River
The Parsnip River is a 240 km long river in central British Columbia, Canada. It flows generally north-westward from the Parsnip Glacier in the Hart Ranges to the Parsnip Reach of Williston Lake, formed by the impounding of the waters of the Peace River by the W.A.C. Bennett Dam in 1968...

 portions of the Northern Trench would be flooded by the damming of the Peace River. Reservoir land acquisition commences. Their selected westerly rail route - the Dease Lake Extension along the A Route - has been, in part, abandoned, and in lesser part been reopened to Takla Siding for logging use.

1964 - US Congress tables the NAWAPA proposal by Parsons Engineering Group - would see flooding of the portions of the Trench as part of a continental-scale water diversion.

1971 - Sir Ranulph Fiennes
Ranulph Fiennes
Sir Ranulph Twisleton-Wykeham-Fiennes, 3rd Baronet, OBE , better known as Ranulph Fiennes, is a British adventurer and holder of several endurance records. He is also a prolific writer. Fiennes served in the British Army for eight years including a period on counter-insurgency service while...

 descends the Trench from Kechika mouth - mostly on foot, partly solo as part of his circum-polar expedition http://www.t5m.com/sir-ranulph-fiennes/. For this and other feats he is later recorded by Guinness Book of Records as the World's 'Greatest Living Explorer.'

1981 - 'Skook' Davidson; long time outfitter proposes a 'federal' national park in the Northern Trench.

1998 - After several years of round table discussions The British Columbia Government takes first legislative steps to establish a 'provincial' Muskwa-Kechika Management Area
Muskwa-Kechika Management Area
The Muskwa-Kechika Management Area is provincially-run tract of land in the far north of British Columbia. It has an advisory board that advises the government on land-use decisions. Established by provincial government legislation in 1998, the area is meant to be preserved as a wild area, but...

 http://www.muskwa-kechika.com/resources/map.asp It covers an area considerably larger than the floor of the Trench and its immediate tributaries.

1999 - Karsten Heuer completes the final section of the Y2Y hike (Yellowstone to Yukon) at Lower Post
http://www.beingcaribou.com/y2yhike/old/route/thehike.htm

2000 - Extension of the Muskwa-Kechika Management Area
Muskwa-Kechika Management Area
The Muskwa-Kechika Management Area is provincially-run tract of land in the far north of British Columbia. It has an advisory board that advises the government on land-use decisions. Established by provincial government legislation in 1998, the area is meant to be preserved as a wild area, but...

 into the Northern Trench. Much of the Northern Rocky Mountain Trench's furthest reach is within this British Columbia Protected Area. Significant exposure is given to the M-KMA in the November 2008 National Geographic Magazine as a follwoup to their partial funding of a recent expedition to Gataga Pass. http://ngm.nationalgeographic.com/2008/11/muskwa-kechika/vaillant-text

In 2009 context the Northern Trench could have, and might yet, become the preferred route for the 120 year old concept of a Canada Alaska Railway
Canada Alaska Railway
Is a Proposed Railway Line Linking the Alaska Railroad near Fairbanks, Alaska to a railway line in northern British Columbia through the Yukon.-First Attempts:...

 http://alaskacanadarail.com/index.html concept. Discussions among feasibility experts still do not seem to favor the B Route despite it being lower, more direct, fewer major river crossings and considerably less snow.

Geology


The Southern Rocky Mountain Trench was created mainly by Cenozoic-aged extension (normal faulting). What little strike-slip movement that is found in the southern trench is not considered significant. The extensional faulting was nonetheless substantial, having extended as deep as 13.5 km (8.4 mi). The southern trench also differs from the northern trench in that it is more sinuous and is asymmetrical in cross-section (perpendicular to its length). The western side of the Southern Rocky Mountain Trench is more subdued and irregular than the east side. During late Paleozoic
Paleozoic
The Paleozoic era is the earliest of three geologic eras of the Phanerozoic eon, spanning from roughly...

 to Mesozoic
Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...

 time, rapid sediment deposition and subsidence
Subsidence
Subsidence is the motion of a surface as it shifts downward relative to a datum such as sea-level. The opposite of subsidence is uplift, which results in an increase in elevation...

 to the west transitioned in the area of the modern Rocky Mountain Trench into a stable continental shelf
Continental shelf
The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...

 in the east. The Nevadan Orogeny
Nevadan orogeny
The Nevadan Orogeny was a major mountain building event that took place along the western edge of ancient North America between the Mid to Late Jurassic...

 destroyed the western wedge of sedimentary rocks during Jurassic to middle Cretaceous time, thrusting them up into metamorphic fold belts. Currently, strata on either side of the Southern Rocky Mountain Trench consist mainly of Precambrian
Precambrian
The Precambrian is the name which describes the large span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale...

 and Paleozoic metasedimentary and sedimentary rocks. Within the trench are unconsolidated Cenozoic sandstones and conglomerates
Conglomerate (geology)
A conglomerate is a rock consisting of individual clasts within a finer-grained matrix that have become cemented together. Conglomerates are sedimentary rocks consisting of rounded fragments and are thus differentiated from breccias, which consist of angular clasts...

.

The aforementioned basement ramp along which orogeny
Orogeny
Orogeny refers to forces and events leading to a severe structural deformation of the Earth's crust due to the engagement of tectonic plates. Response to such engagement results in the formation of long tracts of highly deformed rock called orogens or orogenic belts...

-related thrust fault
Thrust fault
A thrust fault is a type of fault, or break in the Earth's crust across which there has been relative movement, in which rocks of lower stratigraphic position are pushed up and over higher strata. They are often recognized because they place older rocks above younger...

ing and subsequent strike-slip and normal faulting occurred is probably associated with the ancient continental shelf
Continental shelf
The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...

 of Paleozoic and Mesozoic time.

The southern Rocky Mountain Trench comprises approximately one half of the Trench in British Columbia and comprises three regions, the Robson Valley
Robson Valley
The Robson Valley is a geographic region of the Canadian province of British Columbia, comprising the section of the Rocky Mountain Trench that lies southeast of the city of Prince George following the Fraser River to the Yellowhead Pass. The name is derived from Mount Robson, which stands near...

, Columbia Valley
Columbia Valley
The Columbia Valley is the name used for a region in the Rocky Mountain Trench near the headwaters of the Columbia River between the town of Golden and the Canal Flats. The main hub of the valley is the town of Invermere. Other towns include Radium Hot Springs, Windermere and Fairmont Hot Springs...

 and East Kootenay (from north to south). It hosts communities at McBride, Dunster, Tete Jaune, Valemount, Canoe, Donald, Golden, Spillmacheen, Brisco, Edgewater, Radium, Athalmer, Invermere, Windermere, Fairmont, Canal Flats, Skookumchuck, Wasa, Fort Steele, Wardner, Jaffray, Elko and Grasmere. It hosts two major reservoirs - Kinbasket Lake, and Lake Koocanusa (an acronym of Kootenay/Canada/USA.) There are intersections with two other trench features. At the approximate mid point of Kinbasket Lake the now submerged Columbia River exits the Trench in an almost southerly direction toward Revelstoke and flows beyond to its point of exit from Canada south of Trail BC. West of Donald BC, the Beaver river flows in from the south - but it represents the intersection of the lesser but impressive feature called the Purcell Trench. The Purcell Trench as it proceeds southward becomes the valley of the Duncan River
Duncan River
The Duncan River is a long river in the Canadian province of British Columbia. Its drainage basin is in area. It is part of the Columbia River basin, being tributary via Kootenay Lake to the Kootenay River, which is a tributary of the Columbia River...

 and Duncan
Duncan Lake (British Columbia)
Duncan Lake is a man-made reservoir lake in the Kootenay region of British Columbia, Canada, formed by Duncan Dam and about 45 km in length. It is fed by the Duncan River, which forms part of the boundary between the Selkirk Mountains to the west and the Purcell Mountains to the east...

 and Kootenay Lake
Kootenay Lake
Kootenay Lake is a lake located in British Columbia, Canada and is part of theKootenay River. The lake has been raised by the Corra Linn Dam and has a dike system at the southern end, which, along with industry in the 1950s-70s, has changed the ecosystem in and around the water...

s.

Geography


There are four geographic segments of the Southern Rocky Mountain Trench:
  1. The segment of the Trench encompassing the uppermost court of the Fraser River from east of Prince George and continuing southeastward to the town of Valemount is known as the Robson Valley
    Robson Valley
    The Robson Valley is a geographic region of the Canadian province of British Columbia, comprising the section of the Rocky Mountain Trench that lies southeast of the city of Prince George following the Fraser River to the Yellowhead Pass. The name is derived from Mount Robson, which stands near...

    , named after Mount Robson
    Mount Robson
    Mount Robson is the most prominent mountain in North America's Rocky Mountain range; it is also the highest point in the Canadian Rockies. The mountain is located entirely within Mount Robson Provincial Park of British Columbia, and is part of the Rainbow Range. It is commonly thought to be the...

     which overlooks its southern end. Valemount is the Westerly portal to the Yellowhead Pass.
  2. From Valemount and Canoe Southeastward to the eastern egress of Rogers Pass
    Rogers Pass
    Rogers Pass is a high mountain pass through the Selkirk Mountains of British Columbia used by the Canadian Pacific Railway and the Trans-Canada Highway. The pass is a shortcut across the "Big Bend" of the Columbia River from Revelstoke on the west to Donald, near Golden, on the east...

     at Donald, BC just north of the town of Golden
    Golden, British Columbia
    Golden is a town in southeastern British Columbia, Canada, located west of Calgary, Alberta and east of Vancouver.-History:Much of the town's history is tied into the Canadian Pacific Railway and the logging industry...

     the Trench cradles the waters of Kinbasket Lake
    Kinbasket Lake
    Kinbasket Lake is a reservoir on the Columbia River in southeast British Columbia, north of the city of Revelstoke and the town of Golden. The reservoir was created by the construction of the Mica Dam. The lake includes two reaches, Columbia Reach and Canoe Reach , referring to the river valleys...

     the reservoir created by Mica Dam
    Mica Dam
    The Mica Dam is a hydroelectric dam spanning the Columbia River 135 kilometres north of Revelstoke, British Columbia, Canada. Completed in 1973 under the terms of the 1964 Columbia River Treaty, the Mica powerhouse has a generating capacity of . The dam is operated by BC Hydro...

    ; this region before the reservoir was part of the route of the Interprovincial highway, once known as the Big Bend Highway, prior to the 1960s opening of the Roger's Pass section of the Trans-Canada
    Trans-Canada Highway
    The Trans-Canada Highway is a federal-provincial highway system that joins the ten provinces of Canada. It is, along with the Trans-Siberian Highway and Australia's Highway 1, one of the world's longest national highways, with the main route spanning 8,030 km...

    .
  3. The Trench from Golden extending SE to the headwaters of the Columbia River at Columbia Lake
    Columbia Lake
    Columbia Lake is the primary lake at the headwaters of the Columbia River, in British Columbia, Canada. It is fed by several small tributaries. The village of Canal Flats is located at the south end of the lake....

     is known as the Columbia Valley
    Columbia Valley
    The Columbia Valley is the name used for a region in the Rocky Mountain Trench near the headwaters of the Columbia River between the town of Golden and the Canal Flats. The main hub of the valley is the town of Invermere. Other towns include Radium Hot Springs, Windermere and Fairmont Hot Springs...

    . Golden is the westerly portal to the Kicking Horse Pass on Highway #1 eastbound to Aberta.
  4. The southernmost Canadian part of the Trench is the core of a region known as the East Kootenay, comprising the upper of the two Canadian portions of the valley of the Kootenay River
    Kootenay River
    The Kootenay is a major river in southeastern British Columbia, Canada and the northern part of the U.S. states of Montana and Idaho. It is one of the uppermost major tributaries of the Columbia River, which is the largest North American river that empties into the Pacific Ocean...

    . Here, near Cranbrook, British Columbia
    Cranbrook, British Columbia
    Cranbrook, British Columbia is a city in southeast British Columbia, located on the west side of the Kootenay River at its confluence with the St. Mary's River, It is the largest urban centre in the region known as the East Kootenay. As of 2006, Cranbrook's population is 18,267, and the...

    , the Trench is much wider than to the northwest, forming more of a broad basin than the U-shaped valley which typifies most of the Trench elsewhere from Columbia Lake northwards to the Liard. This segment bifurcates near Wasa 100 km north of the US border. The off-shooting western fork contains the City of Cranbrook affords access to the nearby City of Kimberly. Elko is the westerly portal to the Crowsnest Pass on Highway 3 eastbound to Alberta.


The southward transborder extension of the Trench into Montana is the primary containment for Lake Koocanusa, a Kootenay River reservoir created by the Libby Dam near Libby Montana. http://www.fs.fed.us/r1/kootenai/recreation/activitiesx/watersports/reservoir.shtml

Culture and economy


The large valley and tributaries have always offered an economy based on ranching and logging. This has been supplemented by fortuitous locations of several mines - often in side valleys, often producing lead, zinc, coal and gypsum. The Canadian Pacific Railway
Canadian Pacific Railway
The Canadian Pacific Railway , formerly also known as CP Rail between 1968 and 1996, is a historic Canadian Class I railway founded in 1881 and now operated by Canadian Pacific Railway Limited, which began operations as legal owner in a corporate restructuring in 2001...

 (CPR) also constructed a spur line which extends northward up the southern Trench between Cranbrook and Golden. This serves to interconnect the southerly rail route of the Crowsnest Pass to the CPR mainline through Rogers Pass
Rogers Pass
Rogers Pass is a high mountain pass through the Selkirk Mountains of British Columbia used by the Canadian Pacific Railway and the Trans-Canada Highway. The pass is a shortcut across the "Big Bend" of the Columbia River from Revelstoke on the west to Donald, near Golden, on the east...

. Today it carries Crowsnest coal to Tsawassen BC for export. A southerly rail-link through Yahk, BC
Yahk, British Columbia
Yahk is an unincorporated hamlet in southeastern British Columbia, Canada. Yahk Provincial Park borders the village to the south. Yahk is located on the Moyie River.CBC Television talk show The Hour taped a live episode in Yahk on February 9, 2006...

enables freight shipments into Idaho and the Western US.

In more modern times tourism has become an active force in the economy. The Southern Trench is also known for a number of ski resorts in the trench or in the nearby tributary valleys. These destinations include Fairmont, Panorama, Kimberley, Purden, Kicking Horse and the original Bugaboo heli-ski lodge. Numerous other ski touring and back country lodges are also found here. The summer sports of golf, boating, fishing, and hiking round out the appeal to a growing weekend and permanent recreational population.

Hunting, fishing, off-roading, and camping will continue to be attractive pastimes. These include guided activities and individual pursuit of the area.

The generous mix of low elevation, good climate, fine scenery, diverse recreation and resort accommodation has fostered a vacation-based real estate industry for communities and rural areas surrounding Cranbrook, Windermere, Invermere, Radium, and recently - Golden. There are many other local unincorporated communities and post offices.