The Dominion Land Survey: township, range and meridian

Worked example: township 52, range 24, west of the 4th

The township grid reference 52-24-W4 resolves like this:

• W4 — the 4th meridian, at exactly 110°W longitude. It doubles as the Alberta–Saskatchewan border, so a W4 range count starting there puts us in eastern or central Alberta.
• Range 24 — the 24th six-mile column west of 110°W, roughly 220 km from the meridian.
• Township 52 — the 52nd six-mile row north of the 49th parallel, about 490 km north of the U.S. border, which works out to roughly 53.5°N.

Those three numbers intersect at a ~36-square-mile block covering southeast Edmonton. Inside it are 36 numbered sections: section 12, for example, has its centre at 53.476038, -113.405612. Adding a section, quarter or LSD in front of the township reference is how a full legal land description like 4-12-52-24-W4 is built.

How the system works

Townships climb north from the 49th parallel

Township 1 sits against the Canada–U.S. border and the numbers climb northward to roughly township 126 at the top of Alberta. Each township is close to six miles (9.7 km) tall, so multiplying the township number by six miles gives a quick estimate of how far north of the border you are. Every township holds 36 one-square-mile sections, numbered boustrophedon from the southeast corner — see how LSD numbering works for the section and LSD diagrams.

Ranges count out from a meridian

Because the Earth curves, a single origin line could not anchor a survey spanning four provinces. The surveyors instead dropped a series of north–south meridians and restarted the range count at each one. Ranges number westward from each meridian, from range 1 up to about range 34, at which point the next meridian takes over. Manitoba locations east of the Principal Meridian carry an E designation instead (E1/E2), with ranges numbered eastward from 1 to 26 — for example NE-25-10-5-E1.

Correction lines: why prairie roads jog

Range lines run true north, and true-north lines converge as they approach the pole. A range that is a full six miles wide at its baseline is measurably narrower a few townships north. To stop the grid from squeezing itself out of existence, the survey re-measures full six-mile range widths every four townships along east–west correction lines. North of each correction line, the range lines snap back to full width — which is why a north–south prairie grid road suddenly jogs east or west every 24 miles or so before continuing north. The jog in the road is the curvature of the Earth, made visible in gravel.

The Alberta Township System (ATS)

In Alberta the DLS grid is implemented and published as the Alberta Township System (ATS): the province's official record of the same townships, ranges and meridians, maintained with surveyed coordinates for the corners of every township (Government of Alberta / AltaLIS). “ATS” and “DLS” describe the same grid — ATS is Alberta's implementation of it — and the surveyed township corners this site uses in Alberta come from the ATS fabric.

Coverage and limitations

• The township–range–meridian grid covers Alberta, Saskatchewan and Manitoba, plus BC's Peace River Block. The rest of British Columbia uses the NTS/BCGS system instead.
• Real townships deviate from the ideal six-mile math — pure DLS calculation can drift 50–200 m from the monuments on the ground. This site warps the grid through roughly 21,000 townships of surveyed corner coordinates from provincial records, keeping results within tens of metres.
• Coordinates are for navigation and reference only. They are not legal land-survey records and cannot substitute for a survey by a licensed land surveyor.