Glenmore Reservoir

Basic Info
Map Sheets82J/16, 82O/1
Lat / Long50.9833333, -114.1333333
50°58'N, 114°7'W
Area3.84 km2
Max depth21.1 m
Mean depth6.1 m
Dr. Basin Area1210 km2
Dam, WeirDam
Drainage BasinBow River Basin
Camp GroundNone
Boat LaunchPresent
Sport FishNorthern Pike, Mountain Whitefish, Brown Trout, Yellow Perch
Trophic StatusOligotrophic-Mesotrophic
TP x8 µg/L
CHLORO x2 µg/L
TDS x228 mg/L
112
Photo credit: unknown

Introduction

Calgary is very fortunate to have within its city limits such a sparkling blue gem as Glenmore Reservoir (FIGURE 1). This impoundment of the Elbow River not only provides more than half of the city water supply, but it also provides delightful relief from the urban landscape. Surrounded by parks and golf courses, it is a focus for recreation for many of the over half-million residents of this city. The reservoir is in the southwest portion of the city and is reached via 37 Street SW and 24 Street NW on the north side, via 14 Street SW and Heritage Drive on the east side and by 90 Avenue SW and 24 Street SW on the south side (inset, FIGURE 1).

The Glenmore area was named by Sam Livingston, one of the first settlers in the area. He built his home in the Elbow Valley in the 1860s and named the valley Glenmore, which is Gaelic for "big valley" and was the name of his home in Ireland (Calg. Field Nat. Soc. 1975). In 1932, the city of Calgary purchased the land for the reservoir and the Sarcee Indians transferred part of their reserve to the city, including the area of floodplain bounded by the last major meander of the Elbow River upstream of the reservoir. This area is named Weaselhead after the Sarcee Chief who lived there for about 50 years in the late nineteenth and early twentieth centuries (Calg. Field Nat. Soc. 1975). On 31 January 1933, the Glenmore Dam across the Elbow River was completed, and by that summer, Glenmore Reservoir had been created to provide a stable water supply for Calgary.

All but the northeast bay of Glenmore Reservoir is surrounded by city parks (FIGURE 2). North and South Glenmore and Heritage parks provide picnic tables, shelters and washroom facilities; Weaselhead Park is less developed but it is criss-crossed by a network of hiking and bicycle trails. Heritage Park is a replica of an early twentieth century community, with a fur-trade post, a bustling town, a farming community and a sternwheeler that churns through the water of Glenmore Reservoir. South Glenmore Park includes facilities for equestrian events which take place almost every week in summer. Two golf courses, one private and one public, border the northeast bay. Overnight accommodation is not available in the immediate vicinity of the reservoir, but all amenities, including campgrounds, are available within the surrounding city.

Boat access to the reservoir is available at public boat docks on the shore just south of Heritage Park, at the Calgary Sailing School on the south shore and at the Calgary Canoe and Rowing Club on the north shore. As the major use of the reservoir is to supply drinking water for Calgary, maintaining clean water in the reservoir is the top priority. Swimming and wading are prohibited and no pets are allowed in the water. No boating was permitted until 1963; now, some boating is permitted but by-laws are in place to ensure that the water is not contaminated (City Calg. 1989). Restrictions include:

Sport fishing for trout, pike and perch is moderately popular in Glenmore Reservoir and provincial sport fishing regulations apply.

Fishing is prohibited in the Elbow River upstream of the reservoir and in all tributaries to the Elbow River from 1 November through 15 June (Alta. For. Ld. Wild. 1989).

Glenmore is a clear, cold reservoir with low algal concentrations. Aquatic plants grow in the marshy areas at the west end of the reservoir and in a few sheltered areas around the shore.

Drainage Basin Characteristics

The drainage basin for Glenmore Reservoir is that of the Elbow River; it extends westward to the top of the front range of the Rocky Mountains (FIGURE 1). It is very large (1,210 km2), over 300 times the area of the reservoir (3.8 km2) (Tables 1, 2).

The drainage basin includes portions of four ecoregions: Aspen Parkland, Boreal Foothills, Subalpine and Alpine (Strong and Leggat 1981). The drainage area within the Aspen Parkland Ecoregion includes the immediate vicinity of the reservoir and the area of rolling hills extending westward to within a few kilometers of Bragg Creek. The soils are mostly Black Chernozemics with Humic Gleysols in poorly drained depressions. The Elbow River lies in an old braided channel with recent deposits of sandy to coarse loam mixed with ribbons and bars of glaciofluvial gravel. Regosolic soils have developed in some areas, Humic Gleysols are present in poorly drained areas and gravel is exposed in others (MacMillan 1987). The dominant vegetation in this portion of the drainage basin was originally fescue grasslands with trembling aspen, saskatoon and buckbrush in coulees and on north-facing slopes. Much of this region has now been broken for agriculture, primarily mixed farming and improved grazing.

To the west of the Aspen Parkland lies a portion of the Boreal Foothills Ecoregion. This ecoregion encompasses the area around Bragg Creek and continues west to just beyond Ranger Creek and almost as far west as Mount Quirk. Slopes are as steep as 45% and hills rise 150 m above the valley. Higher areas are composed of morainal and colluvial deposits; soils are Orthic and Eluviated Eutric Brunisols and Orthic Gray Luvisols that support closed forests of trembling aspen, pine and spruce (McGregor 1984). In the Elbow Valley, a coarse loamy fluvial veneer overlies glaciofluvial gravel. Terraces and floodplains are gullied. Black Chernozemics are present in well-drained areas and peaty Gleysols are present in poorly drained areas (Scheeler and Veauvy 1977).

Most of the area between the Boreal Foothills Ecoregion and the McConnell Thrust Fault is in the Subalpine Ecoregion (McGregor 1984). Slopes are 30% to over 100% and mountain tops rise over 600 m above the valleys. The soils are primarily Orthic Eutric Brunisols and Orthic Regosols under forests of pine and spruce.

The boundary between the Subalpine and Alpine ecoregions is almost contiguous with the McConnell Thrust Fault, the most easterly fault of the Rocky Mountains. This fault resulted in Cambrian strata being lifted 2 km and moved eastward 30 to 75 km; it is conspicuous today at Mount Yamnuska, which is north of the Bow River, and along Nihahi Ridge in the Elbow Valley. In the Alpine Ecoregion, slopes exceed 100% and mountains rise over 1 000 m above the valleys. The highest point in the basin is Mount Rae, at 3,225 m. Bedrock is exposed in many places and there is poor or no soil development. Orthic and Cumulic Regosols support dwarf scrub in some areas (McGregor 1984).

The major land uses in the basin are urban development near the reservoir, mixed farming and grazing almost as far west as Bragg Creek and recreation west of Bragg Creek. The area west of the Calgary city limits has been developed into numerous residential acreages. The western half of the basin is part of Kananaskis Country and includes numerous campgrounds, day-use areas, hiking and equestrian trails and an off-highway vehicle area at McLean Creek.

The Elbow River provides almost all the inflow to Glenmore Reservoir; there are no other natural defined inflows. Twenty-five storm sewers drain urban areas and flow into the reservoir; six of them are major ones. Four of the large storm sewers enter on the south shore, one enters south of Heritage Park and one enters on the north shore (Hargesheimer and Lewis 1988).

Lake Basin Characteristics

Glenmore Reservoir is an irregularly-shaped impoundment with three arms; the Elbow River enters the northwest arm, the southeast arm fills an old oxbow, and the Elbow River leaves via the Glenmore Dam at the end of the northeast arm. The reservoir is 4.5-km long on its northeast-southwest axis and 4.75-km long on its northwest-southeast axis (TABLE 2, FIGURE 2).

Glenmore Dam is a concrete gravity structure that was built in 1932 and 1933. A road crosses on top of the dam, but as of 1988, this road was closed to motor vehicles. Glenmore Trail crosses the northeast arm of the reservoir on a causeway and a 45-m-long bridge. Approximately one third of the water leaving the reservoir flows through a water intake 6.1 m below the crest level of the dam and provides up to 70% of the city of Calgary's water supply. (The balance of Calgary's water supply is taken from the Bow River just downstream of Bearspaw Reservoir.) The remaining two thirds of the water leaving the reservoir flows through tailrace ports that extend from 1.5 to 7.6 m above the reservoir bottom. The outflowing water forms the Elbow River, which joins the Bow River near the Calgary Zoo (Marshall Macklin Monaghan Ltd. 1985[b]). Another structure, a 1-km-long earthen dyke, retains the southeast arm of the reservoir.

The bottom of the reservoir slopes very gently along most of the northwest arm, but slopes more steeply around the rest of the reservoir, especially in the northeast arm where the bottom drops steeply to the reservoir's maximum depth of 21.1 m.

The water level of the reservoir from 1976 to 1987 is illustrated in Figure 3. The water level is lowered in spring to provide Calgary with some flood protection in the case of sudden snowmelt or heavy rains in the mountains and foothills. The reservoir is filled to its full supply level of 1,076.9 m by about 1 July. Throughout the summer, the level is held as close to the full supply level as the inflow will allow. The level then drops during the winter as inflow is low and water continues to be withdrawn to meet municipal demand. The lowest water level between 1976 and 1987 occurred in 1982 when the water surface was 5.5 m below the full supply level. At this time, the area of the reservoir was approximately 50% of the area at full supply level (FIGURE 4).

Water Quality

The water quality of Glenmore Reservoir and its inflowing storm sewers was monitored intensively by the City of Calgary from 1982 through August 1986 (Marshall Macklin Monaghan Ltd. 1985[a]; 1985[b]; Hargesheimer and Lewis 1988) and is still monitored in an ongoing program.

Glenmore is a freshwater reservoir. The water is well-buffered and the dominant ions are bicarbonate, sulphate and calcium (TABLE 3). More than twenty temperature and dissolved oxygen profiles were taken at each of four sites in the reservoir from April through September in 1985. Throughout this period, there was no evidence of stratification at three of the sites (5- to 7-m deep). At the fourth site, just west of the causeway, weak thermal stratification was apparent for a period of a few days in each of April, May and July (as on 11 July 1985, FIGURE 5). Dissolved oxygen concentrations were always near saturation at all sites and at all depths.

The water in Glenmore Reservoir is very clear and Secchi depths are as deep as 7.5 m. Throughout the summer in 1984 and 1985, most of the reservoir bottom was visible from the surface, although heavy rains increased the turbidity for a few days. Chlorophyll a concentrations were almost always low but average values increased from 1984 to 1986 (TABLE 4). Total phosphorus was analyzed in 395 samples that were collected from Glenmore Reservoir and the upstream portion of the Elbow River. The analytical technique used was sensitive to phosphorus levels over 10 µg/L, but over half of the samples from the reservoir and river were below this detection limit and most of the other samples were barely above it. The low phosphorus concentrations and fairly low mean chlorophyll a concentrations indicate that Glenmore Reservoir is on the borderline between oligotrophic and mesotrophic.

The chemical composition of the base flow in each of the five major storm sewers that empty into Glenmore Reservoir was determined approximately every two weeks from May 1985 through May 1986 (Hargesheimer and Lewis 1988). The storm sewers were not sampled during the spring runoff or during storm events. Phosphorus, arsenic, cadmium, chromium, lead and barium were usually below detection limits in the reservoir but above detection in the base flow of the storm sewers. Organic chemicals such as insecticides, herbicides and other agricultural and industrial compounds were also monitored in the reservoir and in storm sewer base flow. Nine phenolic compounds (such as phenol; 2, 4-D and 2, 4, 5-T) were examined. Phenol was found in 96% of the reservoir samples, and three other phenolics were also frequently found. Twenty-four base-neutral compounds (polyaromatic hydrocarbons, chlorinated organics and industrial residues) were examined in more than 150 reservoir and storm sewer samples. All compounds were consistently higher in the storm sewer samples than in the reservoir samples where they were frequently below detection.

As of July 1989, the City of Calgary was planning to divert the storm effluent from the major storm sewer on the north shore to a retention pond by 1990. The city was also considering the feasibility of options to direct the other five major storm sewers away from the reservoir (Hargesheimer 1989).

Biological Characteristics

Plants

There are no data available on the species of algae or macrophytes in Glenmore Reservoir.

Invertebrates

Zooplankton was briefly sampled in November 1970 (Anderson 1974). The maximum density found was 45 organisms per litre. Six species of cladocerans and four species of copepods were identified.

There are no data on benthic invertebrates in Glenmore Reservoir.

Fish

Six species of fish have been found in Glenmore Reservoir: mountain whitefish, brown trout, northern pike, yellow perch, longnose suckers and white suckers. On 23 and 24 August 1988, Fish and Wildlife Division set two 225-m test nets for a 22-hour period (Alta. For. Ld. Wild. n.d.). A total of 100 fish were caught: 32 northern pike, 25 yellow perch, 6 brown trout, 31 longnose suckers and 6 white suckers. The sport fish caught included large representatives of each species-a 95-cm pike, a 31-cm perch and a 66-cm brown trout. Mountain whitefish are occasionally caught by anglers.

Fish and Wildlife Division stocked the reservoir with rainbow trout, lake trout and kokanee in the mid-1960s (Alta. Ld. For. 1964-1966). These plantings were not successful and the reservoir has not been stocked since.

Sport fishing is only moderately popular in Glenmore Reservoir, more likely due to boating restrictions than to the quality and availability of fish (Lowe 1989).

Wildlife

It is fortunate that the recreation and aesthetic value of the land surrounding Glenmore Reservoir was recognized decades ago and parkland now surrounds the impoundment. The eastern portion has been developed into golf courses, Heritage Park and the Yacht Club, but nearly 280 ha of land south and west of the reservoir has been preserved in its natural state and provides excellent and diverse habitat for wildlife. Plant and animal species likely to be encountered are well described by the Calgary Field Naturalists' Society (1975).

Glenmore Reservoir is extensively used by waterfowl during spring migration. The first ducks arriving near the end of March are Common Mergansers, Common Goldeneye and Mallards. They are soon joined by Canada Geese, Pintails, Blue-winged Teal, Lesser Scaup, American Widgeons, Shovelers and Bufflehead. White-winged Scoters are commonly seen and Surf Scoters are seen more rarely. In 1971, Black Scoters were sighted at the reservoir, the first sighting of this species in Alberta. Whistling Swans and American Coots visit by the hundreds, and Western, Horned and Eared grebes frequent the area.

By the end of May, most of the waterfowl have left, but they return in August with the addition of Hooded Mergansers, but without Whistling Swans, which take a different route south. Only a few Mallards, Pintails, Blue-winged Teal, American Widgeons and occasionally Canada Geese stay to breed, mostly at the western end of the reservoir.

The mudflats at the western end of the reservoir are usually exposed in spring and provide food for thousands of migrating shorebirds as they pass through the area. Black-bellied Plovers, Long-billed Curlews, Willets, Greater and Lesser yellowlegs, Long-billed Dowitchers, Marbled Godwits, Common Snipes and Solitary, Baird's, Least and Semipalmated sandpipers feed on exposed portions of the mudflats.

In winter, large numbers of ducks, mostly Mallards, stay in the open water downstream of the dam. In the winter of 1987/88, approximately 15,000 were seen; in 1988/89, there were 2,500 (Alta. For. Ld. Wild. n.d.).

Mammals seen in the western end of the reservoir include mule and white-tailed deer, black bears, mink, beaver and muskrats (Alta. For. Ld. Wild. n.d.).

J.M. Crosby

References

Alberta Environment. n.d.[a]. Tech. Serv. Div., Hydrol. Br. Unpubl. data, Edmonton.

-----. n.d.[b]. Tech. Serv. Div., Surv. Br. Unpubl. data, Edmonton.

Alberta Forestry, Lands and Wildlife. n.d. Fish Wild. Div. Unpubl. data, Edmonton.

-----. 1989. Guide to sportfishing regulations. Fish Wild. Div. Edmonton.

Alberta Lands and Forests. 1964-1966. Fish planting list. Fish Wild. Div., Edmonton.

Alberta Research Council. 1972. Geological map of Alberta. Nat. Resour. Div., Alta. Geol. Surv. Edmonton.

Anderson, R.S. 1974. Crustacean plankton communities of 340 lakes and ponds in and near the National Parks of the Canadian Rocky Mountains. J. Fish. Res. Bd. Can. 31:855-869.

Calgary Field Naturalists' Society. 1975. Calgary's natural areas: A popular guide. Calg. Field Nat. Soc., Box 981, Calgary.

City of Calgary. n.d. Eng. Dept. Unpubl. data, Calgary.

-----. 1983. Glenmore Park proposed master plan. Rec. Dept., Calgary.

-----. 1989. Welcome to Glenmore Reservoir. Parks Rec. Dept., Calgary.

Energy, Mines and Resources Canada. 1967, 1971, 1977, 1980. National topographic series 1:250000 82O (1967), 821 (1977), 82J (1977) and 1:50000 82J/16 (1971), 82O/1 (1980). Surv. Map. Br., Ottawa.

Environment Canada. 1976-1987. Surface water data. Prep. by Inland Waters Directorate. Water Surv. Can., Water Resour. Br., Ottawa.

-----. 1982. Canadian climate normals, Vol. 7: Bright sunshine (1951-1980). Prep. by Atm. Envir. Serv. Supply Serv. Can., Ottawa.

Hargesheimer, E.E. 1989. City Calg., Eng. Dept., Waterworks Div., Calgary. Pers. comm.

-----, and C.M. Lewis. 1988. Water quality in the Glenmore and Bearspaw Reservoirs. City Calg., Eng. Dept., Waterworks Div., Calgary.

Lowe, D. 1989. Alta. For. Ld. Wild., Fish Wild. Div., Red Deer. Pers. comm.

MacMillan, R.A. 1987. Soil survey of the Calgary urban perimeter. Alta. Soil Surv. Rep. No. 45, Alta. Res. Counc. Bull. No. 54. Alta. Res. Counc., Terrain Sci. Dept., Edmonton.

Marshall Macklin Monaghan Limited. 1985[a]. Elbow River watershed study, phase 2 report, Vol. 2: Water management in other areas: Land use inventory, recreation and stormwater assessment. Prep. for City Calg. by Marshall Macklin Monaghan Ltd., Calgary.

-----. 1985[b]. Elbow River watershed study, phase 2 report, Vol. 3: Final report on water quality program, dye dispersion study, and statistical analyses. Prep. for City Calg. by Envirocon Ltd., Calgary and by Marshall Macklin Monaghan Ltd., Don Mills.

McGregor, C.A. 1984. Ecological land classification of Kananaskis Country. Alta. En. Nat. Resour., Resour. Eval. Plan. Div., Edmonton.

Monenco Consultants Limited. 1980. City of Calgary Glenmore Dam safety evaluation, phase I study, Vol. 1: Study data and results. Prep. for City Calg., Eng. Dept., Calgary.

Scheeler, M.D. and C.F. Veauvy. 1977. Detailed soil survey of Bragg Creek area. Alta. Inst. Pedol. Rep. No. M-77-8. Univ. Alta., Edmonton.

Strong, W.L. and K.R. Leggat. 1981. Ecoregions of Alberta. Alta. En. Nat. Resour., Resour. Eval. Plan. Div., Edmonton.


Figures


Tables