The Dominion Land Survey (DLS) is the method used to divide most of Western Canada into one-square-mile (2.6 km²) sections for agricultural and other purposes. It is based on the layout of the Public Land Survey System used in the United States, but has several differences. The DLS is the dominant survey method in the Prairie provinces, and it is also used in British Columbia along the Railway Belt (near the main line of the Canadian Pacific Railway), and in the Peace River Block in the northeast of the province. (Although British Columbia entered Confederation with control over its own lands, unlike the Northwest Territories and the Prairie provinces, British Columbia transferred these lands to the federal Government as a condition of the building of the Canadian Pacific Railway. The federal government then surveyed these areas under the DLS.)

The survey was begun in 1871, shortly after Manitoba and the North-West Territories became part of Canada, following the purchase of Rupert's Land from the Hudson’s Bay Company. Covering about 800,000 square kilometres (310,000 sq mi), the survey system and its terminology are deeply ingrained in the rural culture of the Prairies. The DLS is the world's largest survey grid laid down in a single integrated system. The first formal survey done in western Canada was by Peter Fidler in 1813.^[2]

The inspiration for the Dominion Land Survey System was the plan for Manitoba (and later Saskatchewan and Alberta) to be agricultural economies. With a large amount of European settlers arriving, Manitoba was undergoing a large change so grasslands and parklands were surveyed, settled, and farmed.^[3] The Dominion Land Survey system was developed because the farm name and field position descriptions used in northern Europe were not organized or flexible enough, and the township and concession system used in eastern Canada was not satisfactory. The first meridian was chosen at 97°27′28.4″ west longitude and was established in 1869. Another 6 meridians were established after.^[4]

A number of places are excluded from the survey system: these include federal lands such as First Nation reserves, federal parks, and air weapon ranges. The surveys do not encroach on reserves because that land was established before the surveys began. When the Hudson's Bay Company relinquished their title to the Dominion on July 15, 1870, via the deed of surrender it received Section 8 and all of Section 26 excluding the northeast quarter. These lands were gradually sold by the company and in 1984 they donated the remaining 5,100 acres (21 km²) to the Saskatchewan Wildlife Association.^[5]

The surveying of western Canada was divided into five basic surveys. Each survey's layout was slightly different from the others. The first survey began in 1871 and ended in 1879 and covers some of southern Manitoba and a little of Saskatchewan. The second and smallest survey, in 1880, was used in only small areas of Saskatchewan. This system differs from the first survey because rather than running section lines parallel to the eastern boundary they run true north-south. The largest and most important of these surveys was the third which covers more land than all the others surveys put together. This survey began in 1881. That method of surveying is still used in Saskatchewan and Manitoba.^[5] The fourth and fifth surveys were used only in some townships in British Columbia.

The reason that the Canadian government was pushing to subdivide Manitoba, Saskatchewan, and Alberta was to affirm Canadian sovereignty over these lands. The United States was undergoing rapid expansion in the 1860s, and the Canadian government was afraid that the Americans would expand into Canadian territory. Canada's introduction of a railway and surveying was a means to discourage American encroachment. Sir John A. Macdonald remarked in 1870 that the Americans "are resolved to do all they can short of war, to get possession of our western territory, and we must take immediate and vigorous steps to counteract them."^[6]

The beginning of the Dominion Land Survey marked a new era for western Canada. Railways were making their way to the West and the population of western regions began to increase. The introduction of the survey system marked the end of the nomadic ways for the First Nations and Metis. This did not go over well and was a catalyst to the events of the Red River Rebellion.^[6]

Being a surveyor was not easy. The hours were long, the time away from civilization was longer, and the elements were unforgiving. A survey party generally consisted of up to 20 members, which would include a party chief, chain men, a cook, people to saw trees, a recorder, and people to turn angles. All travel was either on horseback or by foot. To begin surveying a party chief would have to buy approximately $400 worth of instruments. These instruments included an alidade, dumpy level, theodolite, Gunter's chain (which was replaced by a steel tape), and a solar compass or a vernier compass.^[2]

The Dominion Land Survey system was proposed in 1869 by John Stoughton Dennis. The initial plan, though based on the square townships of the American Public Lands Survey System, involved 9 mile townships divided into sixty-four 800 acre sections consisting of four 200 acre lots each. Work to establish the first meridian and few township outlines began and quickly ended in 1869 when a party of Metis symbolically stepped on a survey chain, beginning the Red River Resistance. Work resumed in 1871; however, the system was redesigned to use 6 mile townships with 640 acre sections based on a suggestion from Lieutenant-Governor of the North-West Territories William McDougall, who advocated that most of the settlers would come from the United States, so it was "advisable to offer them lots of a size to which they have been accustomed." The Dominion Land Survey System still differed from the Public Land System because it contained road allowances.^[6]

The Dominion Land Survey was enormous. Around 178,000,000 acres (720,000 km²) are estimated to have been subdivided into quarter sections, 27 million of which were surveyed by 1883 (14 years after the system's inception). The amount of work undertaken between 1871 and 1930 is given justice by the amount of paper work submitted: the maps, plans and memos transferred by the Canadian government to the provinces filled approximately 200 railway cars. This did not include the closed or dormant files which would be enough to fill 9000 filing cabinets, which would weigh about 227 tons.^[6]

Until very recently, surveying was done with manually controlled instruments to take distance and angular measurements. Distance was measured using either a chain or more recently a transit or range finder. To turn angles a theodolite was used. To find their location they used astronomical observations, and to find elevation levels and barometers were used.^[7] In order to see over long distances towers were constructed from timber in flat and wooded areas.