Nipissing District, Ontario

Net Lake

Eight square kilometers of cold water at Temagami, with 29 islands and 70 kilometers of shoreline, charted to 42.7 meters in the 1970 survey. Three lake trout spawning areas are mapped across 24 hectares, and the aquatic resource record lists 18 species.

Aerial photograph of Net Lake.
Net Lake from the air, COOP2021 2021. Imagery © King’s Printer for Ontario, used under the Open Government Licence – Ontario.
Surface
8.0 km²
Shoreline
70 km65 mainland + 5 islands
Islands
29
Charted depth
42.7 m
Depth contours
42

All figures are derived from Ontario’s survey records.

Where Net Lake is

Net Lake lies in the District of Nipissing, within the Municipality of Temagami.

How deep is Net Lake?

The deepest mapped contour on Net Lake is 42.7 meters, and the water within that boundary descends even farther. Ontario’s bathymetry record holds 42 depth contours for Net Lake.

336.136.124.412.218.312.230.5336.136.119.86.1324.430.536.112.238.136.642.7
The deepest charted contour on Net Lake, 42.7 meters, from the survey of 8 August 1970. The circle marks the centre of that contour, and the water within it is deeper. The survey’s forty-two depth contours are drawn where the province published them, and along the outline where the survey placed them beyond it. Outline from the Ontario Hydro Network. Each contour is labelled with its depth in meters; zoom in where they run close.

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.

Net Lake has 6 Lake Partner monitoring sites. Six have reported phosphorus for the three or more years the province requires before a status is assigned. All are classified oligotrophic.

Lake Partner sites on Net Lake with a quotable phosphorus record
SiteLocationYearsLast sampledClassification
3451/1NT-1 North Arm, N NL-162025oligotrophic
3451/2NT-2 North Arm, Mid NL-262025oligotrophic
3451/3NT-3 North Arm, S NL-362025oligotrophic
3451/4NT-4 South Arm, N NL-462025oligotrophic
3451/5NT-5 South Arm, Mid52022oligotrophic
3451/6NT-6 South Arm, S52025oligotrophic

The longest record is held by site 3451/1 at NT-1 North Arm, N NL-1, sampled over 6 springs to 2025. Its long-term mean phosphorus concentration is 5.8 micrograms per litre, within the oligotrophic band, which extends to 10.

Fish in Net Lake

Ontario’s aquatic resource records name 18 fish species in Net Lake. The province classes the lake as cold water. The record took effect on 22 February 2017, and it compiles what field biologists had reported by then.

Ten of the eighteen species in the province’s records

  • Lake Trout, U.S. Fish and Wildlife ServiceLake Trouttrout and whitefish
  • Lake Whitefish, U.S. Fish and Wildlife ServiceLake Whitefishtrout and whitefish
  • Cisco, Painting by Ellen EdmonsonCiscotrout and whitefish
  • Northern Pike, Drawing by Timothy KneppNorthern Pikepike
  • Walleye, Raver Duane, U.S. Fish and Wildlife ServiceWalleyeperch
  • Yellow Perch, Raver Duane, U.S. Fish and Wildlife ServiceYellow Perchperch
  • Smallmouth Bass, Raver Duane, U.S. Fish and Wildlife ServiceSmallmouth Basssunfish
  • Rock Bass, U.S. Fish and Wildlife ServiceRock Basssunfish
  • Pumpkinseed, Raver Duane, U.S. Fish and Wildlife ServicePumpkinseedsunfish
  • Burbot, USFWS Mountain-PrairieBurbotcod
The other eight species in the province’s records
FamilySpecies
Perchlogperch
Suckerwhite sucker
Minnowbluntnose minnow, common shiner
Sculpinmottled sculpin, slimy sculpin
Trout-perchtrout-perch
Otherictiobus sp.

Spawning areas

Ontario maps 10 fish spawning records within the Net Lake outline, for three species, all of them mapped areas.

By number of records

By area mapped

  • Walleye6 areas6.4 ha
  • Lake Trout3 areas24.1 ha
  • Northern Pike1 area4.9 ha
Spawning records mapped by the province within the Net Lake outline. A record under 100 square meters is drawn as a dot; a spawning area is drawn as the outline mapped. One colour per species, the same as the bars and the list above.

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 Net Lake run from 1947 to 2006 and hold 49 releases. Walleye account for most of the fish: 1,107,215 released in eleven of the years between 1947 and 2006. The last recorded release was 5,450 walleye frys in 2006.

Fish released into Net Lake, 1947 to 2006
SpeciesYearsYears with a releaseFish released
Walleye1947 to 2006111,107,215
Lake Trout1947 to 199031100,059

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

Eating the fish

The 2025 Guide to Eating Ontario Fish carries consumption advice for six species taken from Net Lake, tested for contaminants at a sampling location in Strathy Twp., 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

Lake Trout Mercury, PCB
Length, cm15 to 2020 to 2525 to 3030 to 3535 to 4040 to 4545 to 5050 to 5555 to 6060 to 6565 to 7070 to 75over 75
General population1212128888444442
Sensitive population4444400000000
Lake Whitefish Mercury
Length, cm20 to 2525 to 3030 to 3535 to 4040 to 4545 to 5050 to 55
General population32323216161612
Sensitive population16121212844
Cisco Mercury
Length, cm15 to 2020 to 2525 to 3030 to 3535 to 40
General population3216121212
Sensitive population128444
Walleye Mercury
Length, cm45 to 5050 to 5555 to 6060 to 65
General population8442
Sensitive population0000
Northern Pike Mercury
Length, cm55 to 6060 to 6565 to 7070 to 75
General population8844
Sensitive population0000
Smallmouth Bass Mercury
Length, cm40 to 45
General population8
Sensitive population0

Fisheries Management Zone 11

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

Zone 11 seasons and limits, 2026
SpeciesOpen seasonSport licenceConservation licence
Brook TroutFeb. 15 – Sept. 305, not more than 1 greater than 31 cm (12.2 in.)2, none greater than 31 cm (12.2 in.)
Brown Trout4th Sat. in Apr. – Sept. 3052
Channel CatfishOpen all year126
CrappieOpen all year3010
Lake TroutFebruary 15 to third Sunday in March and third Saturday in May to Labour Day2; ย not more than 1 greater than 40 cm1
Lake WhitefishOpen all year126
Largemouth and Smallmouth Bass or any combinationJanuary 1 to third Sunday in March and third Saturday in May to December 3162
Muskellunge3rd Sat. in June – Dec. 151, must be greater than 122 cm (48 in.)0
Northern PikeJan. 1 – 3rd Sun. in Mar. & 3rd Sat. in May – Dec. 316, not more than 2 greater than 61 cm (24 in.), of which not more than 1 is greater than 86 cm (33.9 in.)2, not more than 1 greater than 61 cm (24 in.), none greater than 86 cm (33.9 in.)
Pacific SalmonOpen all year52
Rainbow TroutOpen all year52
SplakeOpen all year52
SunfishOpen all year5025
Walleye and Sauger or any combinationJan. 1 – 3rd Sun. in Mar. & 3rd Sat. in May – Dec. 314, none between 43 – 60 cm (16.9 – 23.6 in.), not more than 1 greater than 60 cm (23.6 in.)2, none between 43 – 60 cm (16.9 – 23.6 in.), not more than 1 greater than 60 cm (23.6 in.)
Yellow PerchOpen all year5025

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. No waterbody exception names Net Lake.

Fish sanctuaries recorded for Net Lake
WhereClosed
Net Creek – Cassels Twp., from dam on Net Lake to 200 m (656 ft.) in an arc extending out into Cassels LakeNo fishing from Apr. 1 – June 15
Net Lake – 100 m (328 ft.) easterly and westerly of the O.N.R. bridge in Temagami TwpNo fishing from Apr. 1 – June 15
Thieving Bear Creek – Best Twp., from Thieving Bear Lake to 200 m (656 ft.) in an arc extending out into Net LakeNo fishing from Apr. 1 – June 15
Kanichee Creek – Strathy Twp., from Kanichee Lake to 200 m (656 ft.) in an arc extending out into Net LakeNo fishing from Apr. 1 – June 15

Net Lake Ice Fishing

An ice hut on Net Lake must be removed by March 31. Net Lake 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.

Ice conditions

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

Islands and names

Net Lake contains 29 islands in the Ontario Hydro Network’s outline, zero of them over 10 hectares and eighteen under a tenth of a hectare.

12345678910
The ten largest islands, numbered to the table. Areas are measured on the province’s outline.
The ten largest islands
IslandHectares
1unnamed5.2
2unnamed1.5
3unnamed0.8
4unnamed0.5
5unnamed0.3
6unnamed0.2
7unnamed0.2
8unnamed0.2
9unnamed0.1
10unnamed0.1

Official names

Ontario’s geographic names register lists 4 official names on the water and its islands: two bays.

Bays 2

  • Boot Bay
  • Outlet Bay

Nearby lakes

All lakes

Questions about Net Lake

  • How deep is Net Lake?

    Its deepest charted contour is 42.7 meters, and the water within it is deeper.

  • How big is Net Lake?

    Its surface covers 8.0 square kilometers and it holds 29 islands. Of its 70 kilometers of shoreline, 65 kilometers is the mainland shore and 5 kilometers is the shore of the islands.

  • What fish are in Net Lake?

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

  • Is the water clear?

    All six monitoring sites with a phosphorus status are classified oligotrophic, the clearest of the province’s three bands.

A print of Net Lake

Net Lake has not yet been drawn as a print. The lakes drawn so far are on the lake maps page, and a print of Net Lake can be requested by email; whether it can be drawn is confirmed before any payment.

Ask about a Net Lake print

Looking at a property on Net Lake?

Depth and water quality are two records out of many. Our Rural & Cottage Buyer’s Report gathers what the public record holds about one specific address: shore road allowance, road access, wells, flood mapping, Crown land, wetlands and more, read and checked by a person before it is sent.

See what is in the report

What these figures do and do not say

Depth
A depth reading is the distance from the water surface on the day of survey to the lake bottom. Lake levels vary through the season and between years. The depth figure above is the deepest contour charted and is a minimum; the depth within it was not recorded. The figures for Net Lake are read from the province’s bathymetry records within the Ontario Hydro Network’s outline of the lake: the deepest figure is the deepest record inside that outline, and the count is every record inside it.
Shoreline and surface
The shoreline figure is the length of the mainland shore and of every island shore added together, measured on the Ontario Hydro Network’s outline of the lake. The surface figure is the area of water inside that outline, less the area of its islands. The provincial outline is mapped to within a few meters of the shore, and a shoreline measured from a coarser map comes out shorter, which is why a figure published elsewhere is often lower.
Survey coverage
Not every survey covered every arm of a lake, and the province’s index does not always record where a survey ended.
Water quality
Each figure belongs to a single monitoring site and not to the lake as a whole. A bay receiving a creek can read differently from open water half a kilometer away. Sites are matched to Net Lake by name in the province’s records.
Nearby lakes
Distances are measured between lake centres.
Islands and names
Islands are counted and measured on the Ontario Hydro Network outline; names are the register’s, placed by its own coordinate. The register names islands the outline draws as part of a larger one, and the outline holds islands the register has not named, so the two counts differ. The outline carries some lakes across marsh, so a gap in the marsh is drawn as land, and every such gap is included in the island count. Where the register has not named one and it lies mostly inside a wetland in the province’s Wetland With Significance dataset, the page names the wetland and the table of largest islands leaves it out. Wetland boundaries are mapped at their own scale and can cover a small island whole.
Depth contours
Each contour is drawn where the survey placed it, at the survey’s own positional accuracy. The survey carries its own shoreline, which differs from the Ontario Hydro Network’s outline, so a contour near the shore can run to or past the outline. Such a stretch is drawn along the outline, as a drawing convention, and is not the survey’s line there. The contour count in the stat band is the province’s, and it includes the survey’s own shoreline contour, one ring around the mainland and one around each charted island, which the map leaves off; the map’s small print gives the split.
Location
Municipal boundaries are read from the province’s records as published and can lag a boundary change.
Fish
Ontario’s fish records are compilations of existing knowledge from field biologists and do not represent exhaustive inventories. A species that is not listed was not ruled out. The species list carries one date for the whole record and none for any species.
Spawning areas
A spawning area is drawn where the province mapped it, at the province’s stated accuracy, and the record says nothing about how many fish use it in a given year. A nest record is one nest seen on one day; a count of nests is not a count of fish, and a count of records is not a comparison between species. Whether a given piece of work needs an authorization is a determination made by Fisheries and Oceans Canada on the work itself.
Stocking
A stocking record is a release on a date. It says nothing about how many fish survived or about the population in the lake today.
Eating advice
The guide’s advice is for fish taken from the lake at the tested location and applies to the size classes tested. The province’s guide is the authority and is updated each year.
Fishing rules
Seasons and limits are the zone’s, for the year of the dataset the page was built from, and a licence’s own conditions and any waterbody exception apply over them. The province’s regulations summary is the authority.
Ice hut rules
Removal dates and registration rules are set by fisheries management zone and change from time to time. The dates here were read from the province in September 2026. The province’s own fishing regulations are the authority.

Where these figures come from

  • Depth, shoreline, islands and named places: Ontario Ministry of Natural Resources bathymetry and the Ontario Hydro Network, © King’s Printer for Ontario, Open Government Licence – Ontario.
  • Phosphorus and water clarity: Ontario Lake Partner Program, Ministry of the Environment, Conservation and Parks, Open Government Licence – Ontario. Extract built 2026-08-09.
  • Aerial photography: Geospatial Ontario imagery, Open Government Licence – Ontario, released collections only.
  • Official names: Geographic Names Ontario, Ministry of Natural Resources, Open Government Licence – Ontario. Marinas: Overture Maps Foundation places data, CDLA-Permissive 2.0.
  • Lake outline and municipal boundaries: Ontario Hydro Network and Ontario municipal boundary records, Ministry of Natural Resources, Open Government Licence – Ontario.
  • Fish species and thermal regime: Ontario Aquatic Resource Area records. Spawning areas: Ontario Fish Activity Area records. Both Ministry of Natural Resources, Open Government Licence – Ontario.
  • Stocking: Historical Fish Stocking Data and Fish Stocking Data for Recreational Purposes, Ministry of Natural Resources, Open Government Licence – Ontario.
  • Consumption advice: Guide to Eating Ontario Fish advisory database, 2025 edition, Ministry of the Environment, Conservation and Parks, Open Government Licence – Ontario.
  • Seasons and limits: Ontario recreational fishing regulations data, Ministry of Natural Resources, Open Government Licence – Ontario.
  • Fish plates: Duane Raver, U.S. Fish and Wildlife Service; Ellen Edmonson and Hugh Chrisp, New York State Conservation Department; Timothy Knepp, U.S. Fish and Wildlife Service; U.S. Fish and Wildlife Service. All public domain.
  • Ice hut removal dates and registration: Ontario fishing regulations, read September 2026.