## Ice Lake

### Location

Lac Ste. Anne County AB

## Ice Lake

AB

Year: 1972

Citation:

### A study of potential ice fog and low temperature water fog occurrence at Mildred Lake, Alberta

Author(s): Murray, W. A., & Kurtz J.

Year: 1976

Citation:
(1976).   Environmental Research Monograph 1976-4, 63.

Year: 1963

### An assessment of hydro-ecological changes at two closed-drainage basins in the Peace-Athabasca Delta, Alberta, Canada

Author(s): Sinnatamby, R. N.

Year: 2006

Abstract:

Citation:

### An overview of streamflows and lake levels for the Peace, Athabasca and Slave River basins

Author(s): Choles, J., Aitken W., & DeBoer A.

Year: 1996

Abstract:
This report provides a summary of flow and lake level information for water bodies in the Peace, Athabasca and Slave river basins to provide a hydrologic background far many of the other reports published by the Northern River Basins Study. The trends in river flows for both the main stems and significant tributaries, and for lake levels, for both natural and regulated conditions were examined. Ice processes were discussed along with some of the environmental effects. Regulation on the Peace River has altered the hydrologic regime of both the Peace and Slave Rivers, as well as the ice regime on the Peace River as far downstream as Fort Vermilion. Lake Athabasca and Great Slave Lake levels have also been affected by the changes in the Peace River flow regime.

Citation:

### Analysis of climate change impacts on lake ice phenology in Canada using the historical satellite data record

Author(s): Latifovic, R., & Pouliot D.

Year: 2007

Citation:

### Animals on the ice. Seventeen bighorn die

Author(s): Green, M. M.

Year: 1981

Citation:
Green, M. M. (1981).   17(3), 18-19.

### Case studies of river ice breakup

Author(s): Beltaos, S.

Year: 1980

Citation:

### Caves of the Canadian Rockies and Columbia Mountains

Author(s): Rollins, J.

Year: 2004

Citation:

### Correlation of the Campbell strandlines along the northwestern margin of glacial Lake Agassiz

Author(s): Rayburn, J. A.

Year: 1997

Abstract:
The Upper and Lower Campbell strandlines of glacial Lake Agassiz, were correlated from Dauphin, Manitoba northwestward toward the Clearwater River to determine if Lake Agassiz could have overflowed through a northwestern outlet at the Clearwater River into the Mackenzie River drainage basin. The results suggest that the Upper Campbell extended only as far as 350 km southeast of the Clearwater River Two lines of evidence suggest that waters of Upper Campbell-level Lake Agassiz were blocked from reaching the northwestern outlet. They are the termination of the Upper Campbell strandline on the northwestern side of the Wapawekka Hills, in north-central Saskatchewan, and a rapid rise in elevation of the Upper Campbell strandline from the southern side of the Hills to the northern side. The Lower Campbell beach, extends farther to the northwest, possibly reaching the northwestern outlet. A high-resolution differential GPS survey along the correlated Campbell strandlines has allowed the construction of isobases across the western side of the Lake Agassiz basin. The new isobase information indicates that there was more post-glacial rebound in the northwestern region than previously estimated. This reconstruction indicates that, immediately following deglaciation, the Clearwater Spillway may have been below the southern outlet of Lake Agassiz, and acted as a temporary outlet for the lake. It is concluded that the northern side of the Wapawekka Hills was the location of the Keewatin ice margin while the lake remained at the Upper Campbell level. Sometime after 9,350 BP, rapid ice retreat in the northwest exposed the northwestern outlet, allowing a rapid lowering of Lake Agassiz, and temporarily halting drainage through the Mississippi River system. Subsequent rapid isostatic rebound in the northwest would have raised the elevation of the northwestern outlet, causing its abandonment and reopening the southern outlet. (Abstract shortened by UMI.)

Citation:

### Drop stones resulting from snow avalanche deposition on lake ice

Author(s): Luckman, B. H.

Year: 1975

Citation:
Luckman, B. H. (1975).   14(70), 186-188.

### Evidence for ice margin retreat and proglacial Lake (Agassiz?) drainage by about 11 ka, Clearwater spillway area, Saskatchewan

Year: 1992

Citation:
(1992).   Current Research, Part A, Paper 92-1B, 7-11.

Year: 2013

Citation:

Year: 2010

Citation:

### Ice regimes, Lesser Slave Lake and river

Author(s): Ltd., N. H. C.

Year: 1980

Citation:
Ltd., N. H. C. (1980).   Memorandum,

Year: 2008

Citation:

### Late Pleistocene stratigraphy and sedimentology of coarse clastic deposits in the central Canadian Rocky Mountains, Jasper

Author(s): Levson, V. M.

Year: 1995

Abstract:
Six informal lithostratigraphic units are recognized from newly mapped exposures of Late Quaternary deposits in the Jasper region. The oldest deposits consist mainly of locally derived, coarse-grained gravelly diamicton interpreted as large volume, episodic, unchannelled, debris flow deposits. The inferred paleo-environment is a cool temperate, alpine to subalpine alluvial fan setting. Radiocarbon dates indicate that fan sedimentation began prior to 48 ka and continued throughout the Middle Wisconsinan. A unit of stratified gravels and sands interpreted as braided stream glaciofluvial deposits gradationally overlie the paleofan sequences and are distinguished from them by better stratification, sorting, clast roundness and relatively high percentages of distally-derived clasts. Wood from this unit near Jasper town site indicates deposition about 29 ka. Glaciolacustrine sediments overlying this unit in several Front Range valleys, reflect the onset of glaciation in the Athabasca River valley and associated ice-damming of tributary valley streams. Both Rocky Mountain and Cordilleran glaciers advanced through the area, depositing a complex sequence of ice-marginal sediments, basal tills and supraglacial deposits. Several lines of evidence suggest that at the Late Wisconsinan maximum, glaciers flowed out of the Athabasca valley into the conjectural 'ice free' corridor and were deflected southeasterly along the mountain front by the Laurentide ice sheet. During deglaciation, sedimentation in the Athabasca valley was dominated by ice-marginal deposition of glaciofluvial sands and gravels and by paraglacial debris flows. Large medial moraines and debris septa that formed at the confluence of main valley glaciers, such as occupied the Miette and Athabasca valleys, probably led to stagnant ice in the valley centre and associated kame terrace development along the valley sides. A radiocarbon date on shells from a small ice-marginal lake near Pocahontas indicates that glaciers there were in retreat by about 12 ka and alpine glaciers in the region were at or near their present limits by 10 ka. Sedimentologic studies of alluvial fan deposits in the area indicate that fast moving, noncohesive debris flows are prevalent and that the bedrock geology of the fan source areas exerts a strong control on sedimentation patterns. The conclusion that high energy, low frequency, debris flow events are prevalent in the Main Ranges, whereas lower energy, higher frequency events are typical of the Front Ranges is of relevance to modern hazard studies and mitigation efforts in the Canadian Rocky Mountains.

Citation:

### Monitoring ice cover characteristics and behaviour along the Slave River

Year: 2015

Abstract:
For communities along the Slave River, ice is an important component of the traditional way of life. During the winter, a stable ice cover provides local residents with safe access to traditional hunting, trapping, and fishing areas along the river. In recent years, however, local communities have observed changes in ice cover characteristics (e.g. air pocket formation, double layer ice), that have increased the risks associated with travel on the ice. Research to date has focused in the impact of flow regulations, but very little is known about the Slave River ice cover characteristics and behaviour. Remote sensing and field surveys were used to gain an understanding of the ice cover progression along the river during the 2013 – 2014 and 2014 – 2015 winters. RADARSAT- 2 satellite imagery captured changes in the ice cover and identified different types of ice during the entire course of each winter season. The results show that flow regime and meteorological conditions are the main parameters influencing the ice regime along the Slave River.

Citation:

Year: 2010

Citation:

### Oil and Ice

Author(s): Struzik, E.

Year: 2015

Abstract:
When American adventurer Walter Wilcox hiked up to Bow Summit in Banff National Park in 1896, he took a photo of a turquoise lake that caught the eye of a National Geographic editor some time later. In the photo that was eventually published in the magazine, the glacier feeding the lake was just 1 mile upstream, presumably still building, and slowly inching forward.

Citation:
Struzik, E. (2015).   Future Arctic. 17 pages .

### Phytoplankton communities in six eutrophic hardwater lakes in central Alberta and their responses to lime additions

Author(s): Zhang, Y.

Year: 1996

Abstract:
The aim of my study was three-fold: (1) to document natural year-to-year variability in the phytoplankton communities of untreated eutrophic hardwater lakes with relatively low runoffs, (2) to investigate the mechanisms by which Ca(OH)$\sb2$ additions reduce phytoplankton biomass over the short term ($<$20 d), and (3) to identify the effects of treatment on phytoplankton communities in the long term ($>$20 d). The short-term changes in chlorophyll a (chl a), TP and calcium (Ca) concentrations, and pH and turbidity were investigated in four lakes, two dugouts and six limnocorrals after treatment with various Ca(OH)$\sb2$ dosages. Treatments with 250 mg$\rm{\cdot}L\sp{-1}$ of Ca(OH)$\sb2$ in dugouts reduced chl a and TP concentrations in the water by $>$90% and 60%, respectively. Treatment with dosages $\rm{>}75 mg{\cdot}L\sp{-1}$ of Ca(OH)$\sb2$ depressed more chl a and TP concentrations than did dosages $\rm{\le}50 mg{\cdot}L\sp{-1}$ in the limnocorrals. Transitory high pH and turbidity did not reduce phytoplankton biomass in the laboratory. In lakes, treatment with dosages ranging from 25 to 87 mg$\rm{\cdot}L\sp{-1}$ of Ca(OH)$\sb2$ decreased chl a concentrations by 80%, but did not always reduce TP concentration in the water. Effects of lime treatment on phytoplankton communities in the long term were identified by comparing phytoplankton communities in three lime-treated lakes with pre-treatment communities and with communities in three untreated lakes, for the ice-covered period (November to April) and open-water season. Under ice cover, both phytoplankton species composition and biomass fluctuated irregularly from winter-to-winter in all lakes. Treatment effects, if any, on phytoplankton communities were not identified. During the open-water season, mean total phytoplankton biomass and TP concentrations remained unchanged in the year after a single treatment with 72 or 87 mg$\rm\cdot L\sp{-1}\ Ca(OH)\sb2$ in two lakes. In contrast, multiple treatments with dosages ranging from 25 to 75 mg$\rm\cdot L\sp{-1}\ Ca(OH)\sb2$ in Halfmoon Lake reduced mean chl a and TP concentrations by 50% after the first treatment in 1988, and chl a and TP concentrations remained low from 1989 to 1993. Similarly, multiple treatments in Figure Eight Lake, with Ca(OH)$\sb2$ and/or CaCO$\sb3$ at dosages ranging from 5 to 24 mg$\rm\cdot L\sp{-1}$ from 1986 to 1992, reduced mean chl a and TP concentrations from a pre-treatment average (1985 to 1986) of 61 and 161 $\rm\mu g{\cdot}L\sp{-1}$ to 21 and 80 $\rm\mu g{\cdot}L\sp{-1}$ during the repeated treatment years (1987 to 1992). Species diversity decreased in Lofty Lake for up to one year after treatment but was unchanged in N. Halfmoon Lake. Three species of phytoplankton (Gomphosphaeria naegeliana, Lyngbya birgei and Asterionella formosa), which were dominant before treatment, were not recorded for up to two years after lime treatment. More chlorophyte species were found in post- than pre-treatment samples in the three treated lakes. My results suggest that multiple treatments at low to moderate dosages or a single treatment at high dosages are likely required to reduce phytoplankton biomass effectively.

Citation:
Zhang, Y. (1996).   Biological Sciences(Ph. D.), 240.

### Plants and habitats — a consideration of Dene ethnoecology in northwestern Canada

Author(s): Johnson, L. M.

Year: 2008

Abstract:
This paper discusses local understanding of plants and habitats, based on the linguistic evidence [terms for plants and (or) habitats] gathered from ethnobotanical and ethnoecological field work conducted with several Dene Nations of the Canadian northwestern boreal forest and adjacent regions. Nations involved in the study include (Mackenzie Delta Region), Sahtú’otine’ (Great Bear Lake), Kaska Dena (southern Yukon), and Witsuwit’en (northwest British Columbia). Key plant-related habitats include meadow, “swamp”, forest, “willows”, and “brush”. The ethnobotanical classification of willows is explored in conjunction with the explanation of the Dene habitat concept. In local classifications, ‘willow’ is not co-extensive with the genus Salix, but includes a variety of medium to tall woody shrubs that lack either conspicuous flowers, ‘berries’, or thorns; these may include shrubby species of Salix, Alnus, Cornus, and Betula. Shoreline and alpine environments are also discussed as plant habitats. Dene use of alpine environments and resources is ancient, according to the results of recent alpine ice patch research in the Yukon region. The Human dimensions of habitat knowledge are presented. Indigenous concepts of plant taxa and of landscape associations or habitats may differ substantially from those of scientific botany and ecology, and are based in a holistic and interactive ethnoecology. [ABSTRACT FROM AUTHOR]

Citation:
Johnson, L. M. (2008).   Botany. 86(2), 146 - 156.

### Polar Lakes and Rivers: Limnology of Arctic and Antarctic Aquatic Ecosystems

Year: 2009

Abstract:
Lakes, ponds, rivers and streams are prominent features of the Arctic landscape and are also common in many parts of Antarctica. These waters encompass a remarkable variety of conditions for aquatic life, and are proving to be attractive model systems for exploring general ecological themes. Some of these ecosystems have direct global implications, and are also sentinels of global climate change. This book brings together many of the world's leading researchers in polar limnology to describe these diverse aquatic environments and their ecology. It introduces each major ecosystem type including extreme ice shelf and glacial meltwaters; subglacial lakes and rivers; perennially ice-capped lakes; meromictic and epishelf lake systems; tundra lakes and ponds; seasonal streams; and the large Arctic rivers with their associated floodplain lakes. Separate chapters review the geomorphology of polar lake basins, high latitude paleolimnology; biogeochemistry; physical limnology; microbial processes; microbial biodiversity and biogeography; benthic photosynthetic communities including microbial mats and mosses; phytoplankton and primary production; zooplankton and benthic invertebrates; the ecology of high Arctic fish; food web structure and dynamics; and new and emerging themes in high latitude limnology. The book incorporates the overriding theme of climate change impacts as well as direct impacts resulting from human activity.

Citation:

### Reconstruction of Peace River Flood frequency and magnitude for the past - 600 years from Oxbow Lake sediments, Peace-Athabasca Delta, Canada

Author(s): Jarvis, S.

Year: 2008

Abstract:

Citation:

### Substrate freeze-thaw in a drained Alberta fen

Year: 1989

Abstract:
The study of ground frost levels in a drained and undrained forested fen showed a significant delay in thaw as well as lower temperatures at 40 and 60 cm depths in the drained area because of the insulating effect of drier surface peat in the drained area. The undrained area froze to greater depths than the drained area, but thawed more rapidly. Ice was present year-round at 16.7% of the sample points in the portion of the drained area of low hydraulic conductivity. Thickness of the frozen layer appeared to be related to hydraulic conductivity as well as drainage. Thawing from underneath the frozen layer accounted for 38% of total thaw in the undrained area.

Citation:
(1989).   19, 1024-1029.

### The age of extreme oil: 'This used to be a forest?'

Author(s): Kopecky, A.

Year: 2012

Citation:
Kopecky, A. (2012).   The Globe and Mail .

### The Laurentide and Innuitian Ice Sheets During the Last Glacial Maximum

Year: 2002

Abstract:
Abrupt temperature changes in the northern North Atlantic occurred frequently throughout the last glaciation as shown by proxy records from Greenland ice-cores, deepsea cores, and Norway speleothems. Many of these variations occurred in irregular sawtooth cooling cycles which sometimes ended with the deposition of thick layers of ice-rafted debris (IRD) in the deep ocean that are known as Heinrich events. The lithologies of most of the IRD deposits are consistent with widespread surges of the Laurentide Ice-Sheet that may have resulted from the accumulation of deformable sediments in portions of the ice-sheet bed. An alternative conceptual model proposed here to explain the sawtooth coolings and the surges involves repetitive jökulhlaups from a Hudson Bay lake dammed by ice at the mouth of Hudson Strait. The slow sawtooth coolings may be explained by storm track diversion due to progressive coverage of the lake by icebergs, and the surges by abrupt losses of water pressure and buttressing ice-shelves at all ice-sheet fronts in the lake when the ice-dams failed.

Citation:
(2002).   21(1; 2; 3 ), 9-31.

### The Peace-Athabasca Delta: Portrait of a dynamic ecosystem - book review

Author(s): w. Day, J.

Year: 2014

Citation:
w. Day, J. (2014).   Arctic, Antarctic, and Alpine Research. 46(3), 699 - 701.

### Vegetation communities of Marguerite Crag and Tail Wildland Provincial Park

Author(s): Meijer, M.

Year: 2002

Abstract:
This park straddles the Central Mixedwood and Athabasca Plain Natural Subregions transitional area. The terrain in the park is defined by the crag and tail topography created through the actions of glacial ice and meltwater. Crags refer to the knobs or areas of exposed bedrock located on the up-ice side of the landform, while the tails are the trailing elongate bodies on the lee side of the landform and generally consist of erodible bedrock (American Geological Institute 1984 in Alberta Natural Heritage Information Centre 1998). The bedrock patches in this area are generally quite small; however they are very distinct, and do provide defining character for the park landscape This park is located in a relatively remote region of the province and little documented information is currently available for this area. Much of the information currently used to describe this area has been extrapolated from more intensively studied areas near Lake Athabasca to the north and the Athabasca Sand Dunes Ecological Reserve to the northwest. This vegetation study was one component of a multi-disciplinary project, which was conducted to develop a preliminary inventory of the natural components of the area. The objective of this vegetation study was to define some of the more commonly occurring plant communities found within the park and to identify the site conditions with which these communities are associated.

Citation:

### Very high resolution meteorological satellite study of oil sands weather "A feasibility study"

Year: 1977

Abstract:
Imagery from both meteorological and environmental satellite sensor systems was analyzed to determine its applicability in monitoring weather conditions at the Alberta oil sands. Two sensor systems were the objects of investigation, the multispectral scanner (MSS) aboard the environmental LANDSAT satellites and the Very High Resolution Radiometer (VHRR) aboard the NOAA meteorological satellites. Weather conditions such as clear and cold, convective cloudiness, and widespread precipitation were studied with the available satellite imagery. The images and known weather conditions were then compared to determine the capability of the satellite-based sensors to identify specific meteorological phenomena. Particulate and thermal conditions of rivers and lakes were also considered. LANDSAT could resolve meteorological features, such as single cloud elements, but since a given spot is observed only once every nine days, it is quite unsuitable for studying the motion of weather patterns. Slow-changing phenomena such as lake ice, snow cover and particulate content of water bodies are more effectively defined. NOAA satellites provide the twice-daily coverage needed for monitoring fog, smoke, plumes, and small-scale cloud patterns. Unfortunately, the resolution of the NOAA-VHRR was generally inadequate for identification of small meteorological features associated with industrial development. Satellites of the near future will have better instruments for covering the meteorology of the oil sands but no combination of their output is expected to provide ideal time and space resolution. Future studies of this type should find satellite images easily available because of rapidly improving Canadian sources and because of the explanation of image acquisition given in this study.

Citation:

Year: 1976

Abstract:

Citation:

### Water quality overview of Athabasca River Basin

Year: 1985

Abstract:
This report overviews major water quality patterns and trends for the Athabasca River and its major tributaries. In doing so it compares water quality data with surface water quality objectives, identifies spatial and temporal patterns, defines major factors affecting water quality, characterizes the relationship between basin hydrology and water quality and identifies river reaches with similar water quality characteristics. The data analyzed for this overview assessment include historical water quality records collected since 1970 at three fixed station network locations (Jasper, Town of Athabasca and Ft. McMurray), and the results of six basin wide synoptic sampling surveys done seasonally during 1984 and early 1985. The historical data define long term trends, whereas the synoptic surveys provide information on spatial patterns. Results indicate that except for the St. Regis Pulp Mill at Hinton, point source effluents from municipal and industrial plants have no broadly based influence on river water quality. In almost all instances, tributary streams account for 90% or more of all measured constituent 1oadings. At low river flows the Hinton Pulp Mill does affect river water quality for a distance of 50 to 75 km. Many of the Alberta Surface Water Quality Objectives (ASWQUO) are regularly exceeded, however most of these exceedances are not attributable to point or nonpoint source impacts. These provincial objectives do not account for regional variations in natural water quality. Comparison with Environment Canada's use specific water quality objectives indicate Athabasca River water can be used for all beneficial uses except contact recreation, which is 1imited much of the year by low water temperatures and high turbidity. Certain objectives for aquatic life and wildlife are occasionally exceeded, however, these violations are due to natural causes and pending further investigation are not thought to be significant. Three water quality zones can be defined for the Athabasca River. The Foothills Reach, between Jasper Park boundary and Ft. Assiniboine, is characterized by fast flow and good overall water quality conditions. Alkalinity and hardness 1evels are elevated, reflecting the mountain origin of the water; yet the suspended solids, organic carbon and nutrient contents are low. The Hinton pulp mill is the only significant anthropogenic impact. Coal mining activity in the upper tributaries has no broad based effect on the mainstem river system. In contrast, very different water quality conditions are experienced in the river reach situated between Ft. McMurray and Lake Athabasca. Suspended solid 1evels are high much of the year, as are associated parameters like organic carbon, particulate nutrients and metals. These constituents are derived from upstream tributaries and channel re-suspension, rather than municipal or industrial effluents. The lower reach al so has a unique major ion chemistry created by loadings from the Clearwater River. The intermediate reach between Ft. Assiniboine and Ft. McMurray is a transition zone. Along this stretch, alkalinity and hardness levels decrease, while most other constituent concentrations increase due to tributary loadings. Based upon statistical analysis of the historical water quality database three distinct water quality seasons are defined. These include the ice cover interval, and two open water periods, from ice off to July 31 and August 1 to freeze-up. Water quality in the early openwater season is controlled by local and mountain snowmelt runoff and a rising hydrograph. The 1ate openwater season is affected by a falling hydrograph, summer rainstorms in the Interior Plains and maximum instream biological activity. Except for some tributaries the existing database adequately defines baseline water quality conditions throughout the basin. Future work should emphasize expansion of the fixed station water quality monitoring network, definition of river assimilation processes, development of basin specific water quality objectives, further work on trace organic compounds and more detailed definition of parameter inter-correlation and discharge dependence.

Citation:

### Winter and summer hydrometric surveys and modeling in the Athabasca Delta - hydrodynamic & habitat modeling report

Year: 2009

Abstract:
AMEC was retained by CEMA in February 2008 as the prime consultant on a team with Northwest Hydraulic Consultants to execute a detailed bathymetric and hydrometric survey at key locations in the Athabasca River delta. The summer survey was conducted in the 2008 open water season (AMEC-nhc, 2008a) while the winter survey was conducted in February 2008 (AMEC-nhc, 2008b). The surveys focused on four sites within the delta. This report presents the results of a hydrodynamic and fish habitat modeling exercise for Site 2 and Site 4 using the River2D hydrodynamic model. HYDRODYNAMIC MODELING Model boundaries were selected which encompassed all the topographic data in each segment which typically included the top of bank line and one additional survey point taken approximately 10 m inland from the top of bank. The upstream boundary at Site 4 was extended about 400 m upstream of the survey data to allow the model to simulate the velocity distribution measured at Section 4-1Q. The final open water simulations were carried out with bed roughness values of 50, 80, 100 and 120 mm with a bed roughness of 80 mm providing the best overall fit to the observed water surface elevation data. The final under ice simulations were carried out for ice roughness values of 80, 120, 160, 200 and 240 mm with an ice roughness of 160 mm providing the best overall fit to the observed water surface elevation data. Under both open water and under ice conditions, the modeled water surface elevations were found to be insensitive to the roughness values selected but were sensitive to the water level assigned to the downstream boundary. The simulated velocities matched the measured velocities reasonably well under both open water and under ice conditions. FISH HABITAT MODELING Outflow boundary rating curves at Site 2 and Site 4 were developed using an average Lake Athabasca water level computed based on lake level records between 1998 and 2006. Using the open water outflow rating curves, a total of 116 different river discharges at Site 2 and 112 different river discharges at Site 4 were selected to represent both extreme low flow conditions and extreme high (but confined within the channel) flow conditions. Using the under ice outflow rating curves, a total of 20 different river discharges each at Site 2 and Site 4 were selected to represent both extreme low flow conditions and extreme high (but confined within the channel) flow conditions. River2D models were generated for each of the above open water and under ice modeling conditions. For each open water River2D model, the total available wetted area was computed as were the weighted useable area (WUA) values for a total of ten different fish species/life stage combinations. For each under ice River2D model, the total available wetted area was computed as were the weighted useable area (WUA) values for a total of three different fish species/life stage combinations.

Citation:

### Winter Flows in the Mackenzie Drainage System

Author(s): Woo, M. - K., & Thorne R.

Year: 2014

Abstract:
Winter low flow of northern rivers refers to the diminished discharge between the time of rapid flow reduction in the freeze-up period and the arrival of spring freshet, when the flow makes a quick rise. For the Mackenzie River in Canada, the duration of the winter low-flow season so defined varies considerably within the river’s large basin (1.8 million km2); therefore, to give a common time frame that enables between-basin comparison we consider 1 November to 31 March as the winter flow season. Several hydroclimatic conditions influence winter flows to varying degrees. Lengthy periods of sub-freezing temper­atures inhibit rain events and prevent snowmelt, while the formation of river ice increases channel storage at the expense of discharge. Groundwater sustains baseflow, and the flow amount at most stations is related to autumnal discharge, which reflects groundwater storage status in the pre-winter season. Large reservoirs and lakes provide substantially higher winter flows than their neighboring non-lake areas. Winter flow increases downstream as more water is gathered from the expanded drainage network, but flow contribution varies: larger baseflow is delivered from uplands than from lowlands, and discharge from the Williston Lake reservoir, regulated for hydropower production, provides about half of the total winter flow of the Mackenzie. Monotonic linear trends in winter flow are detected statistically for some tributaries, but the effect of short-term flow variability and the confounding influence of managed flow should be evaluated when considering long-term tendencies and their causative factors.

Citation:
(2014).   ARCTIC. 67(2), 238.

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