Lake retention time

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The lake retention time for a body of water with the volume 2,000 m (71,000 cu ft) and the exit flow of 100 m/h (3,500 cu ft/h) is 20 hours. Illustration of the concept "lake retention time".png
The lake retention time for a body of water with the volume 2,000 m (71,000 cu ft) and the exit flow of 100 m/h (3,500 cu ft/h) is 20 hours.

Lake retention time (also called the residence time of lake water, or the water age or flushing time ) is a calculated quantity expressing the mean time that water (or some dissolved substance) spends in a particular lake. At its simplest, this figure is the result of dividing the lake volume by the flow in or out of the lake. It roughly expresses the amount of time taken for a substance introduced into a lake to flow out of it again. The retention time is particularly important where downstream flooding or pollutants are concerned.

Contents

Global retention time

The global retention time for a lake (the overall mean time that water spends in the lake) is calculated by dividing the lake volume by either the mean rate of inflow of all tributaries, or by the mean rate of outflow (ideally including evaporation and seepage). This metric assumes that water in the lake is well-mixed (rather than stratified), so that any portion of the lake water is much like any other. In reality, larger and deeper lakes are generally not well-mixed. Many large lakes can be divided into distinct portions with only limited flow between them. Deep lakes are generally stratified, with deeper water mixing infrequently with surface water. These are often better modeled as several distinct sub-volumes of water. [1]

More specific residence times

It is possible to calculate more specific residence time figures for a particular lake, such as individual residence times for sub-volumes (e.g. particular arms), or a residence time distribution for the various layers of a stratified lake. These figures can often better express the hydrodynamics of the lake. However, any such approach remains a simplification and must be guided by an understanding of the processes operating in the lake.

Two approaches can be used (often in combination) to elucidate how a particular lake works: field measurements and mathematical modeling. One common technique for field measurement is to introduce a tracer into the lake and monitor its movement. This can be a solid tracer, such as a float constructed to be neutrally buoyant within a particular water layer, or sometimes a liquid. This approach is sometimes referred to as using a Lagrangian reference frame. Another field measurement approach, using an Eulerian reference frame, is to capture various properties of the lake water (including mass movement, water temperature, electrical conductivity and levels of dissolved substances, typically oxygen) at various fixed positions in the lake. From these can be constructed an understanding of the dominant processes operating in the various parts of the lake and their range and duration. [1]

Field measurements alone are usually not a reliable basis for generating residence times, mainly because they necessarily represent a small subset of locations and conditions. Therefore, the measurements are generally used as the input for numerical models. In theory it would be possible to integrate a system of hydrodynamic equations with variable boundary conditions over a very long period sufficient for inflowing water particles to exit the lake. One could then calculate the traveling times of the particles using a Lagrangian method. However, this approach exceeds the detail available in current hydrodynamic models and the capacity of current computer resources. Instead, residence time models developed for gas and fluid dynamics, chemical engineering, and bio-hydrodynamics can be adapted to generate residence times for sub-volumes of lakes. [1]

Renewal time

One useful mathematical model is the measurement of how quickly inflows are able to refill a lake. Renewal time is a specific measure of retention time, where the focus is on 'how long does it take to completely replace all water in a lake.' This is modeling can only be done with an accurate budget of all water gained and lost by the system. Renewal time simply becomes a question how quickly could the inflows of the lake fill the entire volume of the basin (this does still assume the outflows are unchanged). For example if Lake Michigan was emptied, it would take 99 years for its tributaries to completely refill the lake. [2]

List of residence times of lake water

The residence time listed is taken from the infobox in the associated article unless otherwise specified.

LakeLocationBasin countriesResidence time
Stausee Ferden Ferden, Valais Switzerland36 hours
Lake Wohlen / Wohlensee Canton of Bern Switzerland2.1 days
Lake Hévíz Hévíz Hungary3 days
Lake St. Clair Great Lakes Canada, United States7 days (2-30 days)
Lake Arapuni North Island New Zealand1 week
Milton Pond Strafford County, New Hampshire, York County, Maine United States11.1 days
Gibson Lake Gibson Generating Station, Princeton, Indiana United States2 weeks
Råcksta Träsk Stockholm Sweden2-3 weeks
Lake Sagami Kanagawa Japan18 days
Lake Cristallina Ticino Switzerland2-4 weeks
Northeast Pond Strafford County, New Hampshire; York County, Maine United States23.7 days
Brandy Pond Naples, Maine United States34 days
Champagne Pool Waiotapu, North Island New Zealand34 days
Prospect reservoir Prospect, New South Wales Australia30-40 days
Sicklasjön Stockholm Sweden1.2 months
Devils Lake Lincoln County, Oregon United States1.8 months
Lough Derg Shannon River Basin Ireland1.8 months
Derwent Water Cumbria United Kingdom55 days
Lake Biel / Bielersee / Lac de Bienne Canton of Bern Switzerland58 days
Veluwemeer Flevoland, Gelderland Netherlands2 months
Hacksjön Tullinge Sweden2.4 months
Kamloops Lake British Columbia Canadaca. 0.2 years (20-340 days)
Malham Tarn North Yorkshire, EnglandUnited Kingdom11 weeks
Lac d'Anterne Passy, Haute-Savoie France90 days
Graham Lake Hancock County, Maine United States3 months
Grand Lac de Clairvaux Jura department, Franche-Comté France3 months
Laduviken Djurgården Sweden3 months
Esthwaite Water Lake District, Cumbria United Kingdom95 days
Trehörningen Huddinge, Southern Stockholm County Sweden98 days
Lac de Divonne Divonne-les-Bains, Ain France100 days
Lake Lesina / Lago di Lesina Province of Foggia, Apulia Italy100 days
Seeweidsee Canton of Zurich Switzerland100 days
Hüttnersee Hütten, Canton of Zurich Switzerland120 days
Lake Lauerz / Lauerzersee Canton of Schwyz Switzerland4 months
Morris Lake Halifax Regional Municipality, Nova Scotia Canada4.1 months
Sobradinho Reservoir Sobradinho, Bahia Brazil4.2 months
Balch Pond Carroll County, New Hampshire; York County, Maine United States136 days
Magelungen Huddinge Sweden4-5 months
Russell Lake Halifax Regional Municipality, Nova Scotia Canada4.6 months
Loweswater Lake District, Cumbria United Kingdom150 days
Lappkärret Stockholm Sweden5 months
Lough Feeagh County Mayo Ireland5.6 months
Egelsee Bubikon, Canton of Zurich Switzerland180 days
Lac de Vouglans Jura, Franche-Comté France180 days
Mettmenhaslisee Canton of Zurich Switzerland180 days
Albysjön Stockholm Sweden6 months
Chesuncook Lake Piscataquis County, Maine United States6 months
Clinton Lake DeWitt County, Illinois United States6 months
Flagstaff Lake Somerset County and Franklin County, Maine United States6 months
Lake Coeur d'Alene Northern Idaho United States6 months
Lac de Saint-Point Doubs department, Franche-Comté France200 days
Kyrksjön Bromma Sweden7 months
Newnan's Lake Gainesville, Florida United States7.2 months
Staples Pond Temple, Maine United States8.2 months
Lac Cornu Chamonix-Mont-Blanc, Haute-Savoie France250 days
Lac du Brévent Chamonix, Haute-Savoie France250 days
Lake Silvaplana / Silvaplanersee / Lej da Silvaplauna Engadin, Grisons Switzerland250 days
Loch Awe Argyll and Bute, ScotlandUnited Kingdom8.4 months
Långsjön Stockholm Sweden9-10 months
Lake Sarnen / Sarnersee Obwalden Switzerland9.6 months
Lake Lovozero Kola Peninsula, Murmansk Oblast Russia10 months
Drevviken Stockholm Sweden10-11 months
Mörtsjön Huddinge Sweden< 1 year
Judarn Bromma, Stockholm Sweden11 months
Coniston Water Lake District, Cumbria United Kingdom340 days
Ullswater Lake District, Cumbria United Kingdom350 days
Khanka Lake Heilongjiang Province, China and Primorsky Krai, Russia China, Russia 1 year
Lake Monona Dane County, Wisconsin United States1.1 years
Long Lake Maine United States1.1 years
Mooselookmeguntic Lake Franklin County, Maine United States1.1 years
Greifensee Canton of Zurich Switzerland408 days
Nainital Lake Uttarakhand India 1.16 years
Manasbal Lake Kashmir Valley India1.2 years
Lake Zurich / Zürichsee Zürich Switzerland 440 days
Tegernsee Bavaria Germany1.28 years
Deer Creek Reservoir Utah United States1.3 year
Orlången Huddinge Sweden1.33 years
Haweswater Reservoir Lake District, Cumbria United Kingdom500 days
Loch Shiel Lochaber, Highland, Scotland United Kingdom1.37 year
Lake Walen /Walensee / Lake Walenstadt St. Gallen, Glarus Switzerland1.4258 years
Keoka Lake Maine United States1.5 years
Kootenay Lake British Columbia Canada 1.5 years
Lake Murten /Lac de Morat /Murtensee Canton of Fribourg, Vaud Switzerland1.6 years
Oeschinen Lake Bernese Oberland Switzerland1.61 years
Lac de Lessy Haute-Savoie France600 days
East Grand Lake Maine / New Brunswick Canada, United States1.7 years
Lake Ikeda Kyūshū islandJapan1.7 years
Lake Poyang Jiujiang China 0.173 years [3]
Faaker See Carinthia Austria1.8 years
Ossiacher See / Lake Ossiach Carinthia Austria1.8 years
Varese Lake/Lago di Varese Province of Varese, Lombardy Italy1.8 years
Long Lost Lake Clearwater County, Minnesota United States1.8 years
Ältasjön Älta Sweden1.8 years
Lake Thun / Thunersee Canton of Bern Switzerland684 days
Green Lake Maine United States1.9 years
Gömmaren Huddinge Sweden1.9 yrs
Loch Lomond Dunbartonshire, Central Scotland Scotland, United Kingdom1.9 years
Lake Balaton Hungary Hungary2 years
Lake Rotoroa Hamilton, Waikato, North Island New Zealandapprox. 2 years
Lake Tūtira Hawke's Bay, North Island New Zealand2 years
Türlersee Canton of Zurich Switzerland730 days
Pfäffikersee Canton of Zurich Switzerland2.085 years
Caniapiscau Reservoir Quebec Canada 2.2 years
Lake Sils / Silsersee /Lej da Segl Engadin, Grisons Switzerland2.2 years
Wilersee Canton of Zug Switzerland2.2 years
Great Pond Maine United States2.3 years
Moberly Lake British Columbia Canada2.4 years
Päijänne Jyväskylä Finland2.5 years
Lake Erie North America Canada, United States2.6 years
Rangeley Lake Franklin County, Maine United States2.6 years
Lake Brienz / Brienzersee Canton of Bern Switzerland2.69 years
Ammersee / Lake Ammer Upper Bavaria Germany2.7 years
Großer Plöner See Schleswig-Holstein Germany3 years
Paudash Lake Haliburton County, Ontario Canada3 years
Moosehead Lake Maine United States3.1 years
Trekanten Stockholm Sweden3.1 years
Great East Lake Carroll County, New Hampshire; York County, Maine United States3.3 years
Lake Champlain North America Canada, United States3.3 years
Flathead Lake Montana United States3.4 years
Lake Lucerne /Vierwaldstättersee Central Switzerland Switzerland3.4 years
Lake Winnipeg Manitoba, CanadaCanada3.5 years
Lac de Paladru Isère France3.6 years
Lake Hallwil / Hallwilersee Aargau Switzerland3.9 years
Flaten Southern Stockholm Sweden4 years
Lake Annecy / Lac d'Annecy Haute-Savoie France4 years
Lake Maggiore / Verbano / Lago Maggiore Lombardy and Piedmont, Italy; Canton Ticino, Switzerland Italy, Switzerland4 years
Todos los Santos Lake Los Lagos Chile 4 years
Lake Baldegg / Baldeggersee Canton of Lucerne Switzerland4.2 years
Lake Iseo / Lago d'Iseo LombardyItaly4.2 years
Lake Constance / Bodensee Germany, Switzerland, Austria Germany, Switzerland, Austria4.3 years
Corey Lake Michigan United States 4.4 years
Elk and Beaver Lakes Saanich, British Columbia Canada4.4 years (Elk Lake),
Lake Como Lombardy Italy 4.5 years
Lake Mendota Wisconsin United States4.5 years
Sea of Galilee Galilee Israel5 years
Walden Pond Massachusetts United States5 years [4]
Bannwaldsee Allgäu, Bavaria Germany5.2 years
Sebago Lake Cumberland County, Maine United States5.1 to 5.4 yrs
Kennisis Lake Haliburton Highlands, Ontario Canada5.26 years
Bay Lake Crow Wing County, Minnesota United States4-7 years
Lake Biwa / 琵琶湖 Shiga Prefecture Japan5.5 years
Jordan Pond Hancock County, Maine United States6 years
Lago di Mergozzo Piedmont Italy6 years
Lake Ontario North America Canada, United States6 years
Lac la Nonne Alberta Canada6.5 years
Lago di Candia Province of Turin Italy6 or 7 years
Ägerisee Canton of Zug Switzerland6.8 years
Loch Morar Morar, Lochaber, Highland, Scotland United Kingdom6.87 years
Lake Powell Utah/Arizona United States7.2 years
Millstätter See / Lake Millstatt Carinthia Austria7.5 years
Moose Lake Alberta Canada7.5 years
Schaalsee Schleswig-Holstein Germany5 to 10 years
Iliamna Lake Lake and Peninsula Borough, Alaska United States7.8 years
Lac du Bourget Savoie, FranceFrance8 years
Odell Lake Klamath County, Oregon United States 8 years
Lake Lugano /Lago di Lugano Ticino, Lombardy Switzerland, Italy8.2 years
Lake Neuchâtel / Lac de Neuchâtel / Neuenburgersee Romandy Switzerland8.2 years
Lake Orta /Lago d’Orta /Cusio Piedmont Italy8.9 years
Weissensee Carinthia Austria9.2 years
Quesnel Lake British Columbia Canada10.1 years
Schweriner See Mecklenburg-Vorpommern Germany10.1 years
Lake Taupō Taupō District, Waikato region, North Island New Zealand10.5 years
Wörthersee / Lake Wörth West of Klagenfurt Austria10.5 years
Lake Chelan Washington United States10.6 years
Lake Geneva Switzerland, France Switzerland, France11.4 years
Lake Wakatipu Queenstown-Lakes District, Otago Region, South Island New Zealandc. 12 years
Higgins Lake Michigan United States12.5 years
Crescent Lake Klamath County, Oregon United States 13 years
Yellowstone Lake Yellowstone National Park, Wyoming United States14 years
Lake Zug / Zugersee Central Switzerland Switzerland14.7 years
Müritz Mecklenburg-Vorpommern Germany15 years (?)
Western Brook Pond Gros Morne National Park, Newfoundland, Newfoundland and Labrador Canada15.4 years
Lake Sempach / Sempachersee Canton of Lucerne Switzerland16.9 years
Skaneateles Lake New York United States18 years
Cayuga Lake New York United States18.2 years
Bear Lake Idaho, Utah United States19.6 years
Green Lake Green Lake County, Wisconsin United States21 years
Lake Starnberg /Starnberger See Bavaria Germany21 years
Lake Huron North America Canada, United States22 years
Lake Garda / Lago di Garda Northern Italy Italy26.8 years
Waldo Lake Cascade Mountains United States32 years
Crystal Lake Benzie County, Michigan United States30 to 60 years
Lake Columbia Jackson County, Michigan United States47 years
Okanagan Lake British Columbia Canada52.8 years
Lake Ohrid Albania, North Macedonia70 years
Lake Michigan Michigan United States99 years
Arendsee Saxony-Anhalt Germany100 years
Gull Lake Alberta Canada>100 years
Lake Yosemite California United States121 years
Great Bear Lake Northwest Territories Canada124 years
Crater Lake Oregon United States157 years
Lake Superior North America Canada, United States191 years
Caspian Sea Azerbaijan, Iran, Kazakhstan, Russia, Turkmenistan 250 years
Lake Baikal Southern Siberia Russia330 years
Lake Tahoe California, Nevada United States650 years
Lake Titicaca Peru, Bolivia 1343 years
Lake Eucumbene Snowy Mountains, New South Wales Australia 1953 years
Lakes Qaban Kazan Russia 2000 years
Lake Tanganyika Burundi, DR Congo, Tanzania, Zambia5500 years
Lake Vostok Antarctica13300 years

See also

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References

  1. 1 2 3 Duwe, Kurt (2003-01-03). "D24: Realistic Residence Times Studies" (PDF). Integrated Water Resource Management for Important Deep European Lakes and their Catchment Areas. EUROLAKES. Archived from the original (PDF) on January 26, 2007. Retrieved 2007-12-11.
  2. Wetzel, R. G. (2001). Limnology 3rd Edition. New York: Academic Press.
  3. "Poyang Lake". International Lake Environment Committee Foundation. Archived from the original on December 13, 2013. Retrieved February 13, 2014.
  4. Colman, John A and Paul J. Friesz. "Geohydrology and Limnology of Walden Pond, Concord, Massachusetts". USGS . Retrieved 2020-07-07.

Further reading