Cochrane District, Ontario

Frederick House Lake

Forty-one square kilometers of cool water between Iroquois Falls and Timmins, with a deepest charted contour of 15.2 meters from the 1971 survey and 53 kilometers of shoreline. The aquatic resource record lists walleye, sauger, lake whitefish and northern pike.

Aerial photograph of Frederick House Lake.
Frederick House Lake from the air, from the Ontario Imagery Web Map Service. The province assembles this frame from three of its imagery collections, because no single flight covers it. Imagery © King’s Printer for Ontario, used under the Open Government Licence – Ontario.
Surface
40.9 km²
Shoreline
53 km51 mainland + 2 islands
Islands
4
Charted depth
15.2 m
Depth contours
17

All figures are derived from Ontario’s survey records.

Where Frederick House Lake is

Frederick House Lake lies in the District of Cochrane, with shoreline in the Town of Iroquois Falls and the City of Timmins.

How deep is Frederick House Lake?

The deepest mapped contour on Frederick House Lake is 15.2 meters, and the water within that boundary descends even farther. Ontario’s bathymetry record holds 17 depth contours for Frederick House Lake.

31.56.19.112.21.531.56.19.115.26.1
The deepest charted contour on Frederick House Lake, 15.2 meters, from the 1971 survey. The circle marks the centre of that contour, and the water within it is deeper. The survey’s seventeen 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.

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

Fish in Frederick House Lake

Ontario’s aquatic resource records name 6 fish species in Frederick House Lake. The province classes the lake as cool water. The record took effect on 12 November 2019, and it compiles what field biologists had reported by then. The province’s other records for the lake name two further species. They appear in the records below.

Five of the eight species in the province’s records

  • Lake Whitefish, U.S. Fish and Wildlife ServiceLake Whitefishtrout and whitefish
  • Northern Pike, Drawing by Timothy KneppNorthern Pikepike
  • Walleye, Raver Duane, U.S. Fish and Wildlife ServiceWalleyeperch
  • Sauger, Duane RaverSaugerperch
  • Yellow Perch, Raver Duane, U.S. Fish and Wildlife ServiceYellow Perchperch
The other three species in the province’s records
FamilySpecies
Suckerlongnose sucker, white sucker
Othergoldeye

Stocking history

Ontario’s stocking records for Frederick House Lake run from 1947 to 1948 and hold 2 releases. Walleye account for most of the fish: 300,000 released in two of the years between 1947 and 1948. The last recorded release was 100,000 walleye frys in 1948.

Fish released into Frederick House Lake, 1947 to 1948
SpeciesYearsYears with a releaseFish released
Walleye1947 to 19482300,000

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

Eating the fish

The 2025 Guide to Eating Ontario Fish carries consumption advice for six species taken from Frederick House Lake, tested for contaminants at a sampling location in Evelyn & Dundonald Twps., Cochrane 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

Walleye Mercury
Length, cm25 to 3030 to 3535 to 4040 to 4545 to 5050 to 5555 to 6060 to 6565 to 7070 to 75over 75
General population16161288444440
Sensitive population84440000000
Northern Pike Mercury, Selenium
Length, cm30 to 3535 to 4040 to 4545 to 5050 to 5555 to 6060 to 6565 to 7070 to 75
General population161616161612844
Sensitive population16168844400
White Sucker Selenium
Length, cm25 to 3030 to 3535 to 4040 to 4545 to 50
General population1616161616
Sensitive population1616161616
Goldeye Mercury, Selenium
Length, cm25 to 3030 to 3535 to 40
General population161616
Sensitive population161212
Longnose Sucker Selenium
Length, cm35 to 4040 to 4545 to 50
General population161616
Sensitive population161612
Sauger Mercury, Selenium
Length, cm20 to 2525 to 3030 to 3535 to 40
General population121284
Sensitive population12440

Fisheries Management Zone 8

Frederick House Lake lies in Fisheries Management Zone 8. Ontario sets its fishing seasons and catch limits by zone.

Zone 8 seasons and limits, 2026
SpeciesOpen seasonSport licenceConservation licence
Brook TroutJan. 1 – Sept. 1552
Lake SturgeonJan. 1 – Apr. 30 & July 1 – Dec. 3100
Lake TroutFeb. 15 – Mar. 15 & 3rd Sat. in May – Sept. 3031
Lake WhitefishOpen all year2512
Largemouth and Smallmouth Bass or any combinationOpen all year62
Northern PikeOpen all year6, 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.)
Rainbow TroutOpen all year52
SplakeOpen all year52
SunfishOpen all year5025
Walleye and Sauger or any combinationJan. 1 – Apr. 14 & 3rd Sat. in May – Dec. 314, not more than 1 greater than 46 cm (18.1 in.)2, not more than 1 greater than 46 cm (18.1 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 Frederick House Lake.

Islands and names

Frederick House Lake contains 4 islands in the Ontario Hydro Network’s outline, zero of them over 10 hectares and zero under a tenth of a hectare.

1234
The four largest islands, numbered to the table. Areas are measured on the province’s outline.
The four largest islands
IslandHectares
1unnamed3.7
2unnamed3.6
3unnamed0.7
4unnamed0.1

Official names

Ontario’s geographic names register lists 3 official names on the water and its islands: two bays. A further 1 named point stands on the mainland shore.

Bays 2

  • Barbers Bay
  • Buffalo Bay

Points on the shore 1

  • Deadman's Point

Nearby lakes

All lakes

Questions about Frederick House Lake

  • How deep is Frederick House Lake?

    Its deepest charted contour is 15.2 meters, and the water within it is deeper.

  • How big is Frederick House Lake?

    Its surface covers 40.9 square kilometers and it holds 4 islands. Of its 53 kilometers of shoreline, 51 kilometers is the mainland shore and 2 kilometers is the shore of the islands.

  • What fish are in Frederick House Lake?

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

A print of Frederick House Lake

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

Ask about a Frederick House Lake print

Looking at a property on Frederick House 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 Frederick House 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.
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.
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.

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.
  • Aerial photography: Ontario Imagery Web Map Service, Open Government Licence – Ontario, drawing this frame from Central Ontario Orthophotography Project 2021, Forest Resources Inventory 2007-2011 and Sentinel 2 2025, satellite.
  • 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; Timothy Knepp, U.S. Fish and Wildlife Service; U.S. Fish and Wildlife Service. All public domain.