Ontario lake depth maps
Ontario Lake Depths
Depth records for 209 Ontario lakes, from the province’s bathymetric surveys. Each lake has a page with its maximum recorded depth, the survey behind it, an aerial photograph, its water quality record and its public access points.
The lakes
Where a depth is marked charted, the figure is the deepest contour on the chart and is a minimum. The water within that contour is deeper, and the records do not state by how much. All other depths are the deepest single sounding recorded.
Shoreline is the length of the mainland shore and of every island shore added together, measured on the province’s outline of the lake. Each lake’s own page gives the two figures separately. Surface is the area of water inside that outline, less the area of its islands.
Surveyed Depths
Ontario has surveyed the depths of several thousand of its lakes over more than half a century. Later surveys were conducted by boat with satellite positioning and produced hundreds of thousands of soundings per lake. Earlier surveys were charted by running transects across the water and drawing depth contours by hand.
A survey may end before the lake does, and the province’s index does not always record where. Each lake is checked against the province’s scanned historic survey sheets before drawing, and its page notes any area the modern survey left unmeasured.
Each lake is available as a print
Every chart is available as a print in two colourways, unframed or framed, printed in Canada, or as a digital file.
See the prints