Lake Nipissing

Where Lake Nipissing is

Lake Nipissing lies in the District of Sudbury, the District of Parry Sound and the District of Nipissing, with shoreline in the Municipality of West Nipissing, the Municipality of Callander, the Municipality of St.-Charles, the Municipality of French River, the Township of Nipissing and the City of North Bay.

How deep is Lake Nipissing?

The deepest mapped contour on Lake Nipissing is 70.0 meters, and the water within that boundary descends even farther. Ontario’s bathymetry record holds 2,691 depth contours for Lake Nipissing.

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 a water sample each spring for phosphorus analysis and measure water clarity through the summer with a Secchi disk.

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 spring phosphorus. Below 10 micrograms per litre is oligotrophic: clear water and low algae. From 10 to 20 is mesotrophic: moderately productive water, with more algae and weed growth than an oligotrophic lake but rarely a bloom. Above 20 is eutrophic: nutrient-rich water, prone to algal blooms and low oxygen at depth.

A Secchi disk is a 20 centimeter 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.

Lake Nipissing has 29 Lake Partner monitoring sites. 22 have reported phosphorus for the three or more years the province requires before a status is assigned. Fourteen of those sites are classified mesotrophic and eight eutrophic.

The longest record is held by site 2467/10 at Centre Callander Bay, sampled over 17 springs to 2025. Its long-term mean phosphorus concentration is 19.37 micrograms per litre, within the mesotrophic band, which runs from 10 to 20. The site’s 42 clarity readings give a median Secchi depth of 1.75 meters.

Water temperature

Ontario’s aquatic resource records class Lake Nipissing as a warm-water lake, with a mean depth of 4.5 meters against its maximum of 70.

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 Lake Nipissing. The province’s longest in-water record is kept on eight research lakes near Dorset, sampled since 1976. A reading is taken at the surface, at one meter, at each meter to seven and then every two meters to the bottom, about every two weeks through the open-water season and about monthly under ice. The record holds 5,240 readings at a depth of one meter.

At one meter the eight lakes track one another closely. On a day when several were sampled, the warmest and the coolest lake differed by about one degree in every month of the year, and a 12 meter deep lake and a 37 meter deep lake read within 0.2 degrees of each other from June to October. The weather of the year, and not the lake, sets most of the width of the band below.

Satellite thermal imagery gives a surface reading on clear days: the Landsat sensors pass over Lake Nipissing every eight days at a resolution of 100 meters. In the province’s record the surface reading and the one meter reading agree to within half a degree nine times in ten in summer.

The water a few meters down is colder than any figure on this chart, in every month of the year.

How depth changes the temperature

The chart below is the province’s record on Harp Lake, 37 meters deep, drawn as the median temperature at each depth for each month over 49 years. In July the water at one meter is 23 degrees, at five meters 15, at seven meters 9, and from 13 meters to the bottom under 6. By October the warm layer has deepened to seven meters and cooled to 11 degrees. In February the whole column sits between 1 and 4 degrees under the ice, coldest at the top.

A shallower lake in the same record warms sooner. Heney Lake, six meters deep, reads about 1.8 degrees warmer than Harp Lake at one meter from January to May, 0.8 degrees warmer from June to August, and the same or cooler from September.

Fish in Lake Nipissing

Ontario’s aquatic resource records name 42 fish species in Lake Nipissing. The province classes the lake as warm water. The record took effect on 8 May 2019, and it compiles what field biologists had reported by then. The province’s other records for the lake name one further species, brook trout. It appears in the records below.

Fourteen of the 43 species in the province’s records

• Lake Whitefishtrout and whitefish
• Ciscotrout and whitefish
• Chinook Salmontrout and whitefish
• Northern Pikepike
• Muskellungepike
• Walleyeperch
• Yellow Perchperch
• Smallmouth Basssunfish
• Largemouth Basssunfish
• Rock Basssunfish
• Pumpkinseedsunfish
• Burbotcod
• Brown Bullheadcatfish
• Lake Sturgeonother

Spawning areas

Ontario maps 204 fish spawning records within the Lake Nipissing outline, for three species. One is records of under 100 square meters each, and the other 203 are mapped areas.

By number of records

By area mapped

• Walleye162 areas28.9 ha
• Northern Pike41 areas2.8 ha
• Muskellunge1 records0 m²

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 Lake Nipissing run from 1946 to 1991 and hold 137 releases. Walleye account for most of the fish: 9,604,578 released in twelve of the years between 1946 and 1991. The last recorded release was 300,000 walleye frys in 1991.

The province’s current stocking programme, recorded from 2016, lists no release into Lake Nipissing.

Eating the fish

The 2025 Guide to Eating Ontario Fish carries consumption advice for fourteen species taken from Lake Nipissing, tested for contaminants at a sampling location in Nipissing Dist. Each figure below is the most meals a month the guide advises for a fish of that length. The advice falls as the fish gets longer, because mercury accumulates over a fish’s life. 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

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

The figures are the number of fish an angler may catch and keep in a day and have in possession, under a sport fishing licence and under a conservation licence. The rows are the whole zone’s, and they apply to every lake in it.

Where a row reads zone-wide, the zone’s own season or limit above applies.

Lake Nipissing Ice Fishing

An ice hut on Lake Nipissing must be removed by March 31. Lake Nipissing lies in fisheries management zone 11, one of the twenty zones Ontario sets its fishing rules by, and one removal date applies across the whole zone.

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 zone 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.

When the ice comes and goes

Ice has been recorded on Lake Nipissing in 62 winters between 1956 and 2019. The median date of complete ice cover is December 8 and the median date of complete ice loss is April 29, a median season of 142 days.

The longest recorded season is 161 days in 1983-84, and the shortest is 127 days in 1987-88.

The record was contributed by W. R. Skinner, Environment Canada to the Global Lake and River Ice Phenology Database, and the ice was read at a weather station rather than from the middle of the lake. Observations were last contributed for 2019, and none have been added since.

Ice conditions

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

Islands and names

Lake Nipissing contains 1037 islands in the Ontario Hydro Network’s outline, 24 of them over 10 hectares and 519 under a tenth of a hectare. Twenty-seven of them lie inside wetlands mapped in the province’s Wetland With Significance dataset.

Official names

Ontario’s geographic names register lists 177 official names on the water and its islands: 94 islands, 43 bays, one shoal, five rocks, two narrows, five points on islands and two rivers. A further 29 named points stand on the mainland shore. The register records the origin of four names.

Bays 43

• Atkin Bay
• Bear Bay
• Bear Bay
• Blind Bay
• Cache Bay
• Callander Bay
• Campbell's Bay
• Collins Bay
• Coté Bay
• Crosspoint Bay
• Deep Bay
• Durrell's Bay
• Dutrisac's Bay
• Fish Bay
• Frank's Bay
• Great North Bay
• Greening's Bay
• Hinchberger Bay
• Hunters Bay
• Keith's Bay
• Kervin's Bay
• Meadow Bay
• Merganser Bay
• Middle West Bay
• Mud Bay
• Muskie Bay
• North Muskrat Bay
• Northwest Bay
• Pike Bay
• Rogers Bay
• Round Bay
• Sandy Bay
• Sawmill Bay
• Shanty Bay
• Simpson's Bay
• South Bay
• South Muskrat Bay
• Sunlit Bay
• Tillicum Bay
• Waltonian Bay
• Warren Bay
• West Bay
• Wigwam Bay

Shoals and rocks 6

• Delorme's Rock
• Gull Rock
• Gull Rock
• Hay Rock
• Pickerel Rock
• Three Sisters

Harbours, cuts and narrows 2

• Doster's Narrow
• Hay Narrows

Points on the shore 29

• Beaucage Point
• Burford Point
• Campbell's Point
• Cross Point
• Deepwater Point
• Dokis Point
• Doran Point
• Ferris Point
• First Rocky Point
• Frank's Point
• Gibraltar Point
• Goulais Island Point
• Jennings Point
• Jocko Point
• Johnston Point
• Keso Point
• Lafleche Point
• Lake Point
• Mousseau Point
• Pike Point
• Pilot Point
• Playfair Point
• Scott Point
• Stormy Point
• Sunset Point
• Wabiscaunk Point
• Wigwam Point
• Windy Point
• Yellek Point

Nearby lakes

• Restoule Lake24 km away
• Trout Lake45 km away
• Red Cedar Lake52 km away
• Lake Nosbonsing54 km away

All lakes

Questions about Lake Nipissing

• How deep is Lake Nipissing?

  Its deepest charted contour is 70 meters, and the water within it is deeper.

• How big is Lake Nipissing?

  Its surface covers 834.5 square kilometers and it holds 1,037 islands. Of its 1,009 kilometers of shoreline, 610 kilometers is the mainland shore and 399 kilometers is the shore of the islands.

• What fish are in Lake Nipissing?

  Ontario’s aquatic resource records name 42 species, among them walleye, smallmouth bass, largemouth bass, northern pike, muskellunge and lake whitefish. The lake’s spawning, consumption and stocking records also name brook trout.