Crawford Lake (Halton Region, Ontario)
Encyclopedia
Crawford Lake is a lake
near the community of Campbellville
, in the town of Milton
, Regional Municipality of Halton, Ontario
, Canada
. It is located within Crawford Lake Conservation Area
, a Regionally Environmentally Sensitive Area, an Ontario Area of Natural and Scientific Interest
, and part of the Niagara Escarpment
World Biosphere Reserve.
The primary inflow to the lake is an unnamed creek, and the primary outflow is an unnamed creek which flows via Limestone Creek and Bronte Creek
to Lake Ontario
.
Crawford Lake is meromictic
, which means it has sequentially-deposited seasonal sediment laminations called varves
at the bottom; these allow for accurate dating of sediment cores and make Crawford Lake a prime site for archeological and geochemical studies. Using pollen analysis
, reconstruction of the history of the area over several hundred years was possible. The pollen analysis revealed the agricultural history of the native Iroquoian Indians and the presence of a pre-European contact village. The Wendat-Huron village has been reconstructed in the conservation area
based on many years of work by archaeologists, historical references, and First Nation's oral traditions. Moreover, geochemical analysis of sediment cores has allowed for the reconstruction of the environmental history (e.g. human impact, pollution, etc.) of the area. For instance, some of this analysis has revealed the trends and sources of air pollution over approximately 150 years.
As a lake that's currently going through eutrophication
, it's predicted that the lake may evaporate in the next few hundred years and following that may become a new Crawford Forest.
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
near the community of Campbellville
Campbellville, Ontario
Campbellville, Ontario, Canada is a community in the geographic township of Nassagaweya in the Town of Milton, Halton Region on the Niagara Escarpment and is a tourist destination for residents of the Greater Toronto Area...
, in the town of Milton
Milton, Ontario
Milton is a town in Southern Ontario, Canada, and part of the Halton Region in the Greater Toronto Area. Milton received a tremendous amount of awareness following the release of the results of the 2006 Census, which indicated that Milton is the fastest growing municipality in the Greater Golden...
, Regional Municipality of Halton, Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. It is located within Crawford Lake Conservation Area
Crawford Lake Conservation Area
Crawford Lake Conservation Area is a conservation area owned and operated by the Conservation Halton near the community of Campbellville in Milton, Regional Municipality of Halton, Ontario, Canada. It is a Regionally Environmentally Sensitive Area, an Ontario Area of Natural and Scientific...
, a Regionally Environmentally Sensitive Area, an Ontario Area of Natural and Scientific Interest
Area of Natural and Scientific Interest
An Area of Natural and Scientific Interest is an official designation by the provincial Government of Ontario in Canada applied to contiguous geographical regions within the province that have geological or ecological features which are significantly representative provincially or regionally...
, and part of the Niagara Escarpment
Niagara Escarpment
The Niagara Escarpment is a long escarpment, or cuesta, in the United States and Canada that runs westward from New York State, through Ontario, Michigan, Wisconsin and Illinois...
World Biosphere Reserve.
The primary inflow to the lake is an unnamed creek, and the primary outflow is an unnamed creek which flows via Limestone Creek and Bronte Creek
Bronte Creek
Bronte Creek is a waterway in the Lake Ontario watershed of Ontario Canada. It runs through Hamilton and Halton Region, with its source in the Niagara Escarpment, passing Bronte Creek Provincial Park, on its way to Lake Ontario at Bronte Harbour in Oakville, where the creek is also known as Twelve...
to Lake Ontario
Lake Ontario
Lake Ontario is one of the five Great Lakes of North America. It is bounded on the north and southwest by the Canadian province of Ontario, and on the south by the American state of New York. Ontario, Canada's most populous province, was named for the lake. In the Wyandot language, ontarío means...
.
Crawford Lake is meromictic
Meromictic
A meromictic lake has layers of water that do not intermix. In ordinary, "holomictic" lakes, at least once each year there is a physical mixing of the surface and the deep waters...
, which means it has sequentially-deposited seasonal sediment laminations called varves
Varve
A varve is an annual layer of sediment or sedimentary rock.The word 'varve' is derived from the Swedish word varv whose meanings and connotations include 'revolution', 'in layers', and 'circle'. The term first appeared as Hvarfig lera on the first map produced by the Geological Survey of Sweden in...
at the bottom; these allow for accurate dating of sediment cores and make Crawford Lake a prime site for archeological and geochemical studies. Using pollen analysis
Pollen analysis
Analysis of the distribution of pollen grains of various species contained in surface layer deposits, especially peat bogs and lake sediments, from which a record of past climate may be inferred. Because the lake sediments accumulate over time, a core of the mud will show that the mud at the bottom...
, reconstruction of the history of the area over several hundred years was possible. The pollen analysis revealed the agricultural history of the native Iroquoian Indians and the presence of a pre-European contact village. The Wendat-Huron village has been reconstructed in the conservation area
Conservation area
A conservation areas is a tract of land that has been awarded protected status in order to ensure that natural features, cultural heritage or biota are safeguarded...
based on many years of work by archaeologists, historical references, and First Nation's oral traditions. Moreover, geochemical analysis of sediment cores has allowed for the reconstruction of the environmental history (e.g. human impact, pollution, etc.) of the area. For instance, some of this analysis has revealed the trends and sources of air pollution over approximately 150 years.
As a lake that's currently going through eutrophication
Eutrophication
Eutrophication or more precisely hypertrophication, is the movement of a body of water′s trophic status in the direction of increasing plant biomass, by the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers or sewage, to an aquatic system...
, it's predicted that the lake may evaporate in the next few hundred years and following that may become a new Crawford Forest.