Red Cedar Lake

Where Red Cedar Lake is

Red Cedar Lake lies in the District of Nipissing, with shoreline in the Municipality of Temagami.

How deep is Red Cedar Lake?

The deepest mapped contour on Red Cedar Lake is 30.5 meters, and the water within that boundary descends even farther. Ontario’s bathymetry record holds 110 depth contours for Red Cedar 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.

No monitoring site on Red Cedar Lake is registered with the Lake Partner Program, so no phosphorus or clarity record exists for the lake.

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

Red Cedar Lake Weather

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

Red Cedar Lake weather

Water temperature

Ontario’s aquatic resource records class Red Cedar Lake as a warm-water lake.

A lake separates into layers through the summer where it is deep enough. Sunlight and wind warm and mix the upper few meters, and beneath a band of rapid cooling, the thermocline, the water stays cold. A shallow lake mixes to the bottom instead and warms through, sooner in spring and later into autumn.

No provincial monitoring station records water temperature on Red Cedar Lake. The LastLake model computes the temperature of its surface water for each day from the daily mean air temperature at Environment Canada’s North Bay A climate station, 56 kilometers from the lake, or the next nearest station when its record is incomplete, and from the lake’s area of 2,343 hectares and its mean depth. The province’s records give no mean depth for Red Cedar Lake; the model uses 4.8 meters, estimated from the lake’s depth contours.

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 Red Cedar Lake carries the model’s figures for the past weeks and the coming week.

See also Lake Water Temperature in Ontario

Fish in Red Cedar Lake

Ontario’s aquatic resource records name 4 fish species in Red Cedar Lake. The province’s other records for the lake name five further species, among them burbot, cisco and lake whitefish. They appear in the records below.

Popular species in the province’s records

• Lake Whitefishtrout and whitefish
• Ciscotrout and whitefish
• Northern Pikepike
• Walleyeperch
• Smallmouth Basssunfish
• Largemouth Basssunfish
• Burbotcod

Spawning areas

Ontario maps 3 fish spawning records within the Red Cedar Lake outline: 3 walleye spawning areas covering 5.97 hectares.

By number of records

By area mapped

• Walleye3 areas6.0 ha

The federal Fisheries Act prohibits the harmful alteration, disruption or destruction of fish habitat without an authorization, so a dock, dredging, infill or shoreline work at a mapped spawning area is reviewed on that basis.

Stocking history

Ontario’s stocking records for Red Cedar Lake run from 1946 to 2005 and hold 48 releases. Walleye account for most of the fish: 2,336,010 released in eleven of the years between 1946 and 1991. The last recorded release was 2,244 lake trout sub-adults in 2005.

The province’s record of stocking for recreational fishing, kept from 2016, lists no release into Red Cedar Lake.

Eating the fish

The 2026 Guide to Eating Ontario Fish carries consumption advice for seven species taken from Red Cedar Lake, tested for contaminants at a sampling location in McCallum Twp., Nipissing 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 11

Red Cedar Lake lies in Fisheries Management Zone 11. Ontario sets its fishing seasons and catch limits by zone.

Fisheries management zones around Red Cedar Lake

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

Red Cedar Lake Ice Fishing

An ice hut on Red Cedar Lake must be removed by March 31. The province sets dates for ice hut removal as a safety measure to ensure huts are removed before thawing occurs. One date applies to an entire fisheries management zone (FMZ). Red Cedar Lake lies within FMZ 11.

An ice hut must also be removed before the ice breaks up, whether or not that date has passed. The deadline clears huts from the ice ahead of the thaw and does not close the fishing season.

Registration is required in FMZ 11 for an ice hut built of anything other than fabric, and for a fabric tent covering seven square meters or more. Registration is free, and the number is displayed on the outside of the hut.

Ice conditions

No public record reports the thickness or the condition of the ice on Red Cedar Lake on any given day. Ontario publishes ice safety guidance for anyone going out on the ice, at ontario.ca.

See also Lake Ice in Ontario and When the Lakes Will Freeze This Winter

Islands and names

Red Cedar Lake contains 94 islands in the Ontario Hydro Network’s outline, six of them over 10 hectares and 44 under a tenth of a hectare.

Official names

Ontario’s geographic names register lists 3 official names on the water and its islands: two bays.

Bays 2

• Campten Bay
• Loon Bay

Nearby lakes

• Lake Temagami33 km away
• Rabbit Lake39 km away
• Obabika Lake43 km away
• Cassels Lake44 km away

All lakes

Questions about Red Cedar Lake

• How deep is Red Cedar Lake?

  Its deepest charted contour is 30.5 meters, and the water within it is deeper.

• How big is Red Cedar Lake?

  Its surface covers 23.4 square kilometers and it holds 94 islands. Of its 165 kilometers of shoreline, 130 kilometers is the mainland shore and 35 kilometers is the shore of the islands.

• What fish are in Red Cedar Lake?

  Ontario’s aquatic resource records name four species: walleye, smallmouth bass, largemouth bass and northern pike. The lake’s spawning, consumption and stocking records also name burbot, cisco, lake whitefish and lake trout.