The headwaters of the Bow River in Alberta, Canada, start at the Bow Glacier and Bow Lake in Banff National Park in the Canadian Rocky Mountains. The glacial stream that feeds Bow Lake has a mean elevation of 2310 metres above sea level (7578 feet above sea level). From there, the river winds through the Alberta foothills onto the prairies, where it meets the Oldman River, the two then forming the South Saskatchewan River. These waters ultimately flow through the Nelson River into Hudson Bay. Major population centres along the Bow River, listed from upstream to downstream, include Lake Louise (population 1,004), Banff (population 10,944), Canmore (population 17,200), Cochrane (population 38,014), and Calgary (population 1,481,806).

In addition, the Bow River is an important source of water for irrigation and drinking water. Between 1910 and 1960, the Bow River and its tributaries were engineered to provide hydroelectric power, primarily for Calgary's use. This significantly altered the river's flow and certain ecosystems.<sup>[3]: 151 </sup>

In the Bow River Basin, there are 20 sub-watersheds that drain into the Bow River.

The Bow River Basin is the traditional territory of the Blackfoot Confederacy, comprising the four Blackfoot Nations: Kainaiwa–Blood Tribe, Siksika, Peigan–Piikani and Aamskapi Pikuni. Today, the basin sits within the traditional area of Treaty 7. The Bow River Basin is also home to the Métis Nation Districts 4 (Rocky View Métis District), 5 (Calgary Nose Hill Métis District), and 6 (Calgary Elbow Métis District).

220px|left|thumb|Morant's Curve, [[Banff National Park]]

First Nations used the river's valleys for the buffalo hunt, in which herds of buffalo were driven over cliffs or into valleys where they could be killed more easily with bows and arrows. Of all the First Nations groups that lived in the Bow River area, only the Nakoda fished the river regularly. While other groups likely caught fish during harder times, they primarily hunted buffalo during the summer season when fishing would have been most plentiful. The river's water naturally attracted game, which the First Nations men also hunted, while women gathered the roots, nuts and berries and processed them for food. The river's game, its local sources for firewood, and its valleys' shelter made the river a common camp location for First Nations during the prairie winters. The danger of crossing the river meant it was a natural boundary for First Nations. The two main fords of the lower Bow River, Blackfoot Crossing and a ford near the Bow's confluence with the Elbow River (where today's central Calgary developed), became important gathering points for First Nations to exchange goods and celebrate festivities. Blackfoot Crossing was used by the Siksika as a winter campsite and is today a part of their reserve.

In order to proceed with railway construction through present-day Alberta and an orderly settlement of the Bow region, the government sought to extinguish title of First Nations to specific lands, and negotiated to do so through treaties. With bison numbers declining and white settlers becoming increasingly common in the region, the Nakoda, Tsuu Tʼina, Kainai, Piikanai, and Siksika met with representatives of the Canadian government at Blackfoot Crossing on the Bow River and signed Treaty 7 on 22 September 1877, ceding lands in exchange for defined reserves.

Calgary Power had problems before this dam was completed in 1911. The Bow River originates from a northern mountain, and its flow varies considerably depending upon the amount and location of winter snowfalls. A storage reservoir was also created within Banff National Park in 1912 at Lake Minnewanka. Despite this additional reservoir and both plants, Calgary Power still struggled to fulfill its power contracts during winter months. In the 1920s, the company began planning new projects to control the Bow River. In this light, rivers could be seen as a series of interdependent parts, and engineering all of them could give technicians control over the system as a whole for the benefit of society.

In this process, Calgary Power ultimately fulfilled conservationist ideology as it increasingly brought the Bow River's interdependent sectors, and thus it as a whole, under control, while failing to embody conservationist ideals of rationally developing the Bow initially. Also in line with conservationism, bureaucrats allowing the construction of the Minnewanka reservoir espoused that the nation's development as a whole superseded the need to protect a small part of Banff National Park's nature.

Between 1910 and 1960, the Bow River was radically changed as it was systematically engineered to control its water flow and provide hydroelectric power. The seasonal summer flooding in Calgary was an issue of the past. Among the plan's critics was the Local Council of Women, reminding the city of its 1955 promise for a river park.

After an Alberta Environment official discovered a toxic "blob" in the Bow in October 1989, human needs again were given priority. Originating from an abandoned wood-preserving plant on the Bow River's bank, the "blob" in the river had released a carcinogenic plume that stretched more than downstream.

Banff

Designation as a national park

In 1887 the Canadian parliament, under the urging of the Canadian Pacific Railway vice-president, William Van Horne, and the federal land agent, William Pearce, created Rocky Mountains Park, later renamed Banff National Park.

! scope=col | Name

! scope=col | Height

! scope=col | Capacity

(MW)

! scope=col | Year of completion

! scope=col | Owner

! scope=col | Reservoir formed

! scope=col | Primary purposes

|-

|Kanasaskis Dam

|8 m

|21

|1913

|TransAlta

|Seebe Reservoir

|Electricity

|-

|Horseshoe Falls Dam

|17 m

|16

|1911

|TransAlta

|Unnamed

|Electricity

|-

|Morley Dam

|49 m

|44

|In planning, (2032 if built)

|Government of Alberta

|

|Flood control, electricity

|-

|Ghost Dam

|30 m

|56

|1929

|TransAlta

|Ghost Lake

|Electricity, recreation and flood control

|-

|Glenbow Dam

|37 m

|28

|In planning (2032 if built)

|Government of Alberta

|

|Flood control, recreation and electricity

|-

|Bearspaw Dam

|10 m

|17

|1954

|TransAlta

|Bearspaw Reservoir

|Drinking water and electricity

|-

|Calgary Weir

|6 m

|0

|1944

|Western Irrigation District

|

|Irrigation

|-

|Carseland Wier

|3 m

|0

|1968

|Bow River Irrigation District

|

|Irrigation

|-

|Bassano Dam

|12 m

|0

|1935

|Eastern Irrigation District

|Unnamed

|Irrigation

|}

The Bow River supplies the water for three irrigation districts in southern Alberta: the Eastern, Western, and Bow River irrigation districts.

Eastern Irrigation District

The Eastern Irrigation District (EID), headquartered in Brooks, Alberta, was originally part of land that the federal government granted to the Canadian Pacific Railway in lieu of a portion of the payment for the construction of the railway. In 1929 the CPR split the property into two parts and divested itself of both sections. In 1935 a delegation of irrigation farmers took control of the eastern section and established the EID.

The EID, diverting its water at the Bassano and Newell dams, is the largest private land owner in Alberta. Recently the EID began promoting the recreational possibilities that have developed alongside the district's irrigation development. The EID currently owns and operates the Rolling Hills Reservoir Campground. In 1951, the province of Alberta also established Kinbrook Island Provincial Park on the eastern bank of the Newell reservoir, which has been stocked with native species of fish.

Western Irrigation District

The Western Irrigation District (WID), headquartered in Strathmore, Alberta, was the second half of the land divested by the CPR. The WID was established in 1944.

The water of the WID, diverted at the Calgary Weir, is instrumental to southern Alberta agriculture and, unlike the other two districts, supports the urban needs city of Calgary. It is able to supply both agricultural and urban needs since the WID has higher levels of rainfall than the other two districts, and it receives much of Calgary's storm water.

Bow River Irrigation District

The Bow River Irrigation District (BRID), headquartered in Vauxhall, Alberta, was created in 1968, making it the most recent district to be supplied by the Bow. The BRID diverts the Bow at the Carseland weir and also uses the McGregor, Travers, and Little Bow dams. Each has a reservoir that is also used for recreational purposes.

In March 2012, the citizens of the BRID voted in favour of expanding the area of the district by . An expansion of passed in 2004 as well. This means that, for the second time in eight years, the BRID increased its demand on the Bow River by roughly 10&nbsp;percent.

Irrigation today

Of the 45 crops that are grown in the Bow River basin, only 10 could be produced without irrigation.

Because of the dependence of the region on Bow River irrigation water, in the early 21st century all three irrigation districts began to make major changes in order to continue to serve their large mandated areas. In 2006, as a part of the "Water for Life Initiative", the Alberta government placed a moratorium on any new licences for water use from the Bow, Oldman, and South Saskatchewan River basins. The government also requested that the three irrigation districts increase their efficiency by 30&nbsp;percent. The irrigation districts are improving their irrigation system by changing most canals to pipelines in order to decrease contamination, spillage, and loss of water to evaporation. A drawback of this change is that trees must be cleared to prevent roots from damaging the pipeline, changing the habitat.

in 1987 the EID in association with the Alberta Fish and Wildlife Division and Ducks Unlimited Canada established a partnership to create additional wildlife habitat within the Eastern Irrigation District's boundaries. This demonstrated the EID's goal of encouraging wildlife in order to contribute to the growth of its tourist sector. Hunting and fishing are now promoted on the EID's website.

Water Quality

Water quality in the Bow River, as in all rivers, is influenced by several factors. The surficial geology and soils of the catchment basin, the plant and animal communities, seasonal differences, precipitation and flow all are natural factors that impact water quality. Human activities impact water quality by clearing land, agricultural uses, dams, and urbanization.

Key water quality parameters are regularly monitored in the different sub-watersheds of the Bow River. The government of Alberta puts out guidelines for these water quality parameters, which include:

{| class="wikitable"

!Parameter

!Description

|-

|Ammonia

|Type of nitrogen, high levels cause eutrophication and toxicity

|-

|Chloride

|High levels cause toxicity to aquatic life

|-

|Carbon, Total Organic

|Measures organic material in water

|-

|Escherichia coli (E. coli)

|Indicates fecal contamination, risks to human health

|-

|Nitrate

|Type of nitrogen, high levels can cause eutrophication

|-

|Nitrogen (Total)

|All nitrogen compounds, high levels can cause eutrophication

|-

|pH

|Measurement of how acidic or basic water is

|-

|Phosphorus (Dissolved)

|High levels can cause eutrophication

|-

|Phosphorus (Total)

|High levels can cause eutrophication

|-

|Total Suspended Solids

|High levels can harm aquatic life

|-

|Turbidity

|High levels can harm aquatic life

|-

|Sodium Adsorption Ratio

|Measures suitability for drinking and irrigation

|-

|Specific conductance

|Measures salts in water

|-

|Sulphate

|High levels cause toxicity to aquatic life

|}

Water quality in the Bow River changes seasonally, and along its length. In general, water quality along the entire length of the Bow River is good, but there are some parameters that occasionally cause concerns:

Ammonia can enter water due to natural breakdown of organic material, from agricultural runoff and from industrial processes, but this compound is rarely at levels high enough to cause concern in the Bow River.

Chlorides can come from natural sources but in the Bow River Basin, mostly enter the Bow River when roads are salted in the winter. Chlorides are higher within and just downstream of the City of Calgary, and this parameter has occasionally exceeded provincial guideline levels.

Total organic carbon comes from organic material entering the river. There is rarely enough organic carbon in the Bow River to cause concern.

E. coli enters the Bow River from wild and domestic animal feces and human sewage.  E. coli levels are occasionally above levels recommended for recreational waters, especially within and downstream of the City of Calgary.

Total nitrogen and nitrate enter the Bow River from atmospheric deposition, degradation of organic material, fertilizer runoff and sewage discharges. Levels of nitrogen in the Bow River are generally low, even below wastewater treatment plants in the City of Calgary and in agricultural areas.

Dissolved and total phosphorus levels enter the Bow River from sewage and agricultural runoff, and levels of these compounds can be high in the agricultural areas of the lower Bow River.

The sodium adsorption ratio indicates the amount of sodium relative to calcium and magnesium in water. This is an indicator of how good the water is for irrigation, and this indicator rarely causes concern in the Bow River.

Total suspended solids and turbidity are due to particles entering the Bow River. These are generally high during the spring snowmelt, as runoff brings soil into the river. However, these parameters can also become high if construction or other soil disturbances cause soil to enter the river. This can occur anywhere along the length of the river.

Sulphates can enter water from weathering of natural minerals and also from industrial sources. Sulphates are high at some locations in the Bow River basin, but the reasons are not very clear.

Recreation

thumb|upright=1.2|The Bow River near [[Canmore, Alberta|Canmore]]

The Bow River provides habitat for wildlife and many opportunities for recreation such as fishing and boating. Both fly fishermen and spinner fishermen share the river in all four seasons of the year. Serious anglers from all over the world visit the Bow River for its thriving population of brown trout and rainbow trout. The Bow River holds a resident population of rainbow and brown trout that has one of the best growth rates to be found on any river system in the world today. A trout that is 4 to 5 years old will be around long, and the Bow River holds many fish that are this size or larger. Mainly the river is fished south of the city of Calgary, past where the water treatment sites dump into the river. The volume of nutrients and number of fish are higher there.

Outdoor adventurers use primarily three types of boats to enjoy the river, the inflatable boat, the johnboat and the canoe. There are several spots on the river to launch watercraft, including Graves Landing, Highway 22X Bridge, Policeman's Flats and McKinnon Flats.

The Bow River pathway, is developed on both banks of the river throughout the city of Calgary and is used for cycling, hiking, jogging, as well as rollerblading and skateboarding. Along the Bow River pathway, many people partake in canoeing, kayaking, rafting, paddle boarding, and other activities on the water. Dog owners and families often use the river banks and beaches for outdoor recreation.

Recreation and industrial development

The recreation and tourism sector of the Bow developed closely alongside the river's water irrigation projects. Similarity, after a three-year refurbishing project ending in 1987, the town of Bassano, about northeast of the dam, began advertising the Bassano dam as a tourist attraction for the town. At this point the Bassano dam now also started offering group tours, fishing and picnic areas, and a scenic viewpoint.

Communities have also recently begun to appear around Ghost Dam as well.

Calgary's weir project (Harvie Passage)

In 1904 the Bow River Weir was constructed close to Calgary's downtown core in order to divert water into the Western Irrigation District. Since its construction a side effect of the weir had been that it created a circulating wave, with a lethal and powerful undertow, immediately downstream of it. Because rafting, canoeing, and kayaking down the Bow River are such popular summer activities, there had been many fatalities. Furthermore, because fish were not able to pass through the structure, they too became trapped in the circulating wave and a dense, unnatural concentration of pelicans congregated immediately following the weir.

In order to combat the circulating wave and undertow, in August 2007 the province of Alberta through the Alberta Lottery fund, in conjunction with the Calgary Foundation and the City of Calgary, began construction of the Bow River Weir paddle around, named the Harvie Passage. The passage allowed for the wave to be dispersed over a set of several smaller rapids while still supplying water to its irrigation district. Altogether, the paddle around cost $18 million and was completed in the spring of 2012.

In June 2013, just a year after the project was completed, Calgary was hit with an epic 100 year flood, and all of the Harvie Passage work was destroyed. After that flood, the passage was closed to the public and a safety boom ahead of the rapids was re-installed. It was estimated that rebuilding the Harvie Passage to the original intent of the project (completed in 2012) would cost $23.4 million.

By 2021, construction on the Harvie Passage was complete. The passage was redesigned to withstand a flood similar to the one that damaged the previous structures.

Ecology

A type of diatom called Didymosphenia geminata, a type of algae commonly called "rock snot", grows in the Bow River and many of the tributaries. This diatom will occasionally form large blooms which are unsightly but do not appear to do damage to fish stocks. Despite fears that this diatom is invasive, there is evidence that it has been present in the Bow Basin since at least 1860, when it was known as Gomphonema geminatum,

Tributaries

;Banff National Park

  • Mosquito Creek
  • Noseeum Creek
  • Missing Lake
  • Pipestone River
  • <small>Molar Creek, Little Pipestone Creek</small>
  • Paradise Creek
  • Corral Creek
  • Moraine Creek
  • Baker Creek
  • <small>Wildflower Creek</small>
  • Taylor Creek
  • Silverton Creek
  • Altrude Creek
  • Johnston Creek
  • Redearth Creek
  • <small>Pharaoh Creek</small>
  • Wolverine Creek
  • Ranger Creek
  • Healy Creek
  • <small>Brewster Creek, Howard Douglas Creek, Fatigue Creek</small>
  • Sundance Creek
  • Forty Mile Creek
  • Spray River
  • Cascade River
  • Carrot Creek

;Foothills and plains

  • Policeman Creek
  • Cougar Creek
  • Three Sisters Creek
  • Stewart Creek
  • Wind Creek
  • <small>Pigeon Creek</small>
  • Grotto Creek
  • Exshaw Creek
  • Heart Creek
  • Jura Creek
  • Kananaskis River
  • Joshua Creek
  • Chiniki Creek
  • Jacob Creek
  • Ghost River
  • Spencer Creek
  • Beaupre Creek
  • Grand Valley Creek
  • McClennan Creek
  • Horse Creek
  • Jumpingpound Creek
  • <small>Towers Creek, Pile of Bones Creek, Park Creek</small>
  • Bighill Creek
  • Elbow River
  • Nose Creek
  • <small>West Nose Creek</small>
  • W.I.D. Canal
  • Pine Creek
  • Highwood River
  • Arrowwood Creek
  • Crowfoot River
  • Matzhiwin Creek

Many lakes, glacial and artificial are found in the Bow Valley: Bow Lake, Hector Lake, Vermilion Lakes, Gap Lake, Lac des Arcs, and Ghost Lake on the upper course, and a few man-made reservoirs along the lower course.

<gallery class="center">

File:Bow Lake-Bow Glacier.jpg|Bow Glacier

Image:Bow Lake 2.jpg|Bow River originates in Bow Lake.

Image:VermillionLakes2001-09-28.jpg|Vermilion Lakes formed along the Bow River

Image:Lac Des Arcs, Alberta HPIM4262.JPG|Lac des Arcs formed along Bow River

Image:Bow River-27527-2.jpg|Hoodoos above the Bow River.

Image:Ghost Lake-aerial01.Alberta.CA.jpg|Ghost Lake in Bow Valley

Image:Bow River Calgary 2.jpg|Crowchild Trail crossing the river in Calgary, downtown in background

</gallery>

See also

  • List of rivers of Alberta

References

Sources

Further reading

  • Bow River Basin Council