White Otter Lake

Where White Otter Lake is

White Otter Lake lies in the District of Kenora.

How deep is White Otter Lake?

The deepest mapped contour on White Otter Lake is 48.8 meters, and the water within that boundary descends even farther. Ontario’s bathymetry record holds 118 depth contours for White Otter Lake.

See also Ontario's Largest and Deepest Lakes

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.

Water quality

Ontario’s Lake Partner Program is a volunteer monitoring network. Participants collect water samples for phosphorus analysis and measure water clarity through the summer with a Secchi disk. Most sites are sampled for phosphorus once a year, in spring, and some several times a year between spring and fall. Phosphorus in many lakes rises through the summer, so the two kinds of average are measured on different bases.

Phosphorus is the nutrient that controls how much algae a lake can grow. A lake with little phosphorus stays clear and supports cold-water fish such as lake trout. As phosphorus rises, algae increase, the water clouds, and oxygen in the deep water falls as the algae decay. The province classifies each monitoring site by its average phosphorus:

• Oligotrophic, below 10 micrograms per litre: clear water and low algae.
• Mesotrophic, from 10 to 20: moderately productive water, with more algae and weed growth than an oligotrophic lake but rarely a bloom.
• Eutrophic, above 20: nutrient-rich water, prone to algal blooms and low oxygen at depth.

White Otter Lake has 1 Lake Partner monitoring site, which has yet reported phosphorus for the three years the province requires before a status is assigned.

A Secchi disk is a white or black-and-white plate lowered on a marked line until it disappears from view. The depth at which it vanishes is the Secchi depth, a direct measure of water clarity. Clearer water gives a deeper reading.

See also Lake Water Quality and Blue-Green Algae in Ontario

White Otter Lake Weather

The weather page for White Otter Lake carries the forecast over the water, wave heights across the lake, and the modelled water temperature.

White Otter Lake weather

Water temperature

Ontario’s aquatic resource records class White Otter Lake as a cold-water lake, with a mean depth of 22.1 meters against its maximum of 48.8.

A deep lake separates into layers through the summer. Sunlight and wind warm and mix the upper few meters, and beneath a band of rapid cooling, the thermocline, the water stays cold through the whole season. A mean depth of 22.1 meters places most of White Otter Lake’s volume in that cold layer, which is the condition lake trout and lake whitefish require.

No provincial monitoring station records water temperature on White Otter Lake. The LastLake model computes the temperature of its surface water for each day from the daily mean air temperature at Environment Canada’s Atikokan climate station, 42 kilometers from the lake, and from the lake’s area of 8,629 hectares and its mean depth of 22.1 meters.

Each day’s figure carries the model’s typical error for that month on lakes of the same size. The figure in the chart below is the temperature near the surface, away from the shoreline. Bays, shallows and water deeper below the surface differ in temperature. Temperature is not measured when ice covers the lake. The weather page for White Otter Lake carries the model’s figures for the past weeks and the coming week.

See also Lake Water Temperature in Ontario

Fish in White Otter Lake

Ontario’s aquatic resource records name 20 fish species in White Otter Lake.

Popular species in the province’s records

• Lake Trouttrout and whitefish
• Lake Whitefishtrout and whitefish
• Ciscotrout and whitefish
• Northern Pikepike
• Walleyeperch
• Yellow Perchperch
• Smallmouth Basssunfish
• Burbotcod

Eating the fish

The 2026 Guide to Eating Ontario Fish carries consumption advice for seven species taken from White Otter Lake, tested for contaminants at a sampling location in Kenora Dist. Each figure below is the most meals a month the guide advises for a fish of that length. Where mercury sets the advice, the figure falls as the fish gets longer, because mercury accumulates over a fish’s life. Where the guide has no result yet for certain contaminants at a location, it sets a precautionary limit of 16 meals a month. A zero means the guide advises no meals of that fish at that size.

General population: adultsSensitive population: children under fifteen, women who are or may become pregnant

Fisheries Management Zone 5

White Otter Lake lies in Fisheries Management Zone 5. Ontario sets its fishing seasons and catch limits by zone.

Fisheries management zones around White Otter Lake

Zone-wide, Smelt may not be used as bait or possessed for use as bait.

See also Fishing Seasons in Ontario, Zone by Zone and Fish Stocking in Ontario Lakes

Islands and names

White Otter Lake contains 56 islands in the Ontario Hydro Network’s outline, nine of them over 10 hectares and twenty under a tenth of a hectare. Big Island, at 673 hectares, is larger than the next ten together, which cover 213.

Official names

Ontario’s geographic names register lists 11 official names on the water and its islands: 4 islands, four bays and one narrows.

Bays 4

• Ann Bay
• Lost Bay
• McOuat Bay
• Walleye Bay

Harbours, cuts and narrows 1

• Jackfish Narrows

Nearby lakes

• Marmion Lake34 km away
• Eva Lake67 km away
• Dinorwic Lake78 km away
• Wabigoon Lake93 km away

All lakes

Questions about White Otter Lake

• How deep is White Otter Lake?

  Its deepest charted contour is 48.8 meters, and the water within it is deeper.

• How big is White Otter Lake?

  Its surface covers 86.3 square kilometers and it holds 56 islands. Of its 238 kilometers of shoreline, 182 kilometers is the mainland shore and 56 kilometers is the shore of the islands.

• What fish are in White Otter Lake?

  Ontario’s aquatic resource records name twenty species, among them lake trout, walleye, smallmouth bass, northern pike, lake whitefish and yellow perch.