Leeds and Grenville, Ontario

Charleston Lake

A maximum recorded depth of 97.3 meters, determined from 171,568 soundings taken during Ontario's 2009 survey, and 152 islands inside 179 kilometers of shoreline.

Surface: 26.4 km²
Shoreline: 179 km94 mainland + 85 islands
Islands: 152
Max depth: 97.3 m
Soundings: 171,568
Survey behind the depths: 2004 and 2009

All figures are derived from Ontario’s survey records.

Where Charleston Lake is

Charleston Lake lies in the United Counties of Leeds and Grenville, with shoreline in the Township of Athens and the Township of Leeds and the Thousand Islands.

How deep is Charleston Lake?

Charleston Lake reaches a maximum recorded depth of 97.3 meters, determined from 171,568 soundings taken in Ontario’s 2004 and 2009.

The deepest sounding on Charleston Lake, 97.3 meters, recorded 1 August 2009. Outline from the Ontario Hydro Network.

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.

Charleston Lake has 11 Lake Partner monitoring sites. Seven have reported phosphorus for the three or more years the province requires before a status is assigned. Two of those sites are classified oligotrophic and five mesotrophic.

Lake Partner sites on Charleston Lake with a quotable phosphorus record
Site	Location	Years	Last sampled	Classification
822/1	Big Water	23	2025	mesotrophic
822/2	Deep Water,Runnings B	23	2025	mesotrophic
822/3	Donaldson Bay	23	2025	oligotrophic
822/4	Eastern Water	23	2025	oligotrophic
822/5	N end, Goose Island	23	2025	mesotrophic
822/6	Southern Water	23	2025	mesotrophic
822/7	Webster Bay	23	2025	mesotrophic

The longest record is held by site 822/1 at Big Water, sampled over 23 springs to 2025. Its long-term mean phosphorus concentration is 10.13 micrograms per litre, within the mesotrophic band, which runs from 10 to 20. The site’s 140 clarity readings give a median Secchi depth of 6.0 meters.

Median Secchi depth by year at site 822/1, surface at the top. The thin line through each bar spans the shallowest and deepest reading that year, and the row beneath the years gives the number of readings. Years without readings are blank.

Fish in Charleston Lake

Ontario’s aquatic resource records name 31 fish species in Charleston Lake. The province classes the lake as cold water. The record took effect on 6 January 2011, and it compiles what field biologists had reported by then.

Thirteen of the 31 species in the province’s records

Lake Trouttrout and whitefish
Lake Whitefishtrout and whitefish
Ciscotrout and whitefish
Northern Pikepike
Yellow Perchperch
Smallmouth Basssunfish
Largemouth Basssunfish
Black Crappiesunfish
Rock Basssunfish
Pumpkinseedsunfish
Bluegillsunfish
Burbotcod
Brown Bullheadcatfish

The other eighteen species in the province’s records
Family	Species
Pike	grass pickerel
Perch	johnny darter x tesselated darter
Catfish	yellow bullhead
Sucker	white sucker
Minnow	blackchin shiner, blacknose shiner, bluntnose minnow, emerald shiner, golden shiner, northern redbelly dace
Sculpin	mottled sculpin, slimy sculpin
Herring	alewife
Eel	american eel
Bowfin	bowfin
Killifish	banded killifish
Silverside	brook silverside
Other	pumpkinseed x bluegill

Spawning areas

Ontario maps 349 fish spawning records within the Charleston Lake outline, for nine species, all of them mapped areas. Fifty-six of the areas are one outline mapped for largemouth bass, yellow perch and northern pike alike, and 34 more are filed under more than one species. An outline filed for more than one species is drawn once, striped in each of their colours.

By number of records

By area mapped

Smallmouth Bass111 areas161.6 ha
Largemouth Bass74 areas35.0 ha
Yellow Perch66 areas31.8 ha
Northern Pike62 areas15.5 ha
Lake Trout24 areas6.4 ha
Brown Bullhead5 areas2.7 ha
Pumpkinseed4 areas1.6 ha
Black Crappie2 areas1.0 ha
Lake Whitefish1 area200 m²

Spawning records mapped by the province within the Charleston 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. An outline filed for more than one species is striped in each of their colours; zoom in to read the stripes.

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 Charleston Lake run from 1947 to 2011 and hold 113 releases. Lake Trout account for most of the fish: 850,673 released in 57 of the years between 1947 and 2011. The last recorded release was 5,720 lake trout yearlings in 2011.

Fish released into Charleston Lake, 1947 to 2011
Species	Years	Years with a release	Fish released
Lake Trout	1947 to 2011	57	850,673
Largemouth Bass	1950 to 1967	11	74,800
Smallmouth Bass	1947 to 1967	15	44,300

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

Eating the fish

The 2025 Guide to Eating Ontario Fish carries consumption advice for ten species taken from Charleston Lake, tested for contaminants at a sampling location in Leeds & Lansdowne Twps. 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, cm	15 to 20	20 to 25	25 to 30	30 to 35	35 to 40	40 to 45	45 to 50	50 to 55	55 to 60	60 to 65	65 to 70	70 to 75	over 75
General population	16	16	16	16	12	12	12	12	8	8	4	4	0
Sensitive population	8	8	4	4	4	4	4	4	4	4	0	0	0

Northern Pike Mercury
Length, cm	35 to 40	40 to 45	45 to 50	50 to 55	55 to 60	60 to 65	65 to 70	70 to 75	over 75
General population	16	16	16	16	16	12	8	4	0
Sensitive population	12	12	8	4	4	4	0	0	0

Smallmouth Bass Mercury
Length, cm	20 to 25	25 to 30	30 to 35	35 to 40	40 to 45
General population	16	16	16	8	4
Sensitive population	8	4	4	4	0

Largemouth Bass Mercury
Length, cm	15 to 20	20 to 25	25 to 30	30 to 35	35 to 40	40 to 45	45 to 50
General population	32	16	16	16	16	16	2
Sensitive population	12	8	8	8	4	4	0

Yellow Perch Mercury
Length, cm	15 to 20	20 to 25	25 to 30
General population	16	16	12
Sensitive population	8	4	4

Pumpkinseed Mercury
Length, cm	15 to 20
General population	12
Sensitive population	4

Burbot Mercury
Length, cm	35 to 40	40 to 45	45 to 50	50 to 55	55 to 60	60 to 65	65 to 70
General population	16	12	8	8	4	4	4
Sensitive population	4	4	4	0	0	0	0

Brown Bullhead no contaminant listed
Length, cm	20 to 25	25 to 30
General population	32	32
Sensitive population	16	12

White Sucker Mercury
Length, cm	40 to 45	45 to 50	50 to 55
General population	16	16	16
Sensitive population	4	4	4

Bluegill Mercury
Length, cm	15 to 20
General population	16
Sensitive population	4

Fisheries Management Zone 18

Charleston Lake lies in Fisheries Management Zone 18. Ontario sets its fishing seasons and catch limits by zone.

Zone 18 seasons and limits, 2026
Species	Open season	Sport licence	Conservation licence
Brook Trout	Open all year	5	2
Brown Trout	Open all year	5	2
Channel Catfish	Open all year	12	6
Crappie	Open all year	30	10
Lake Trout	4th Sat. in May – Sept. 8	2	1
Lake Whitefish	Open all year	12	6
Largemouth and Smallmouth Bass or any combination	3rd Sat. in June – Dec. 15	6	2
Muskellunge	1st Sat. in June – Dec. 15	1, must be greater than 91 cm (36 in.)	0
Northern Pike	Jan. 1 – Mar. 31 & 2nd Sat. in May – Dec. 31	6	2
Pacific Salmon	Open all year	5	2
Rainbow Trout	Open all year	5	2
Splake	Open all year	5	2
Sunfish	Open all year	300, only 30 may be greater than 18 cm (7.1 in.)	15
Walleye and Sauger or any combination	Jan. 1 – Mar. 1 & 2nd Sat. in May – Dec. 31	4, must be between 40 – 50 cm (15.7 – 19.7 in.)	2, must be between 40 – 50 cm (15.7 – 19.7 in.)
Yellow Perch	Open all year	50	25

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 Charleston Lake.

Charleston Lake Ice Fishing

An ice hut on Charleston Lake must be removed by March 15. Charleston Lake lies in fisheries management zone 18, 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 18 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 Charleston Lake on any given day. Ontario publishes ice safety guidance for anyone going out on the ice, at ontario.ca.

Getting on the water

Two access marks are mapped on Charleston Lake: two marinas.

Every access mark on Charleston Lake, numbered to the list. Colour is the kind of record: blue a boat launch, green shoreline access, yellow a marina, peach a beach, white a lock, grey a dam. Zoom in where marks overlap.

Marinas 2

1Kelsey's MarinaOverture Places
2Lakeline Lodge & MarinaOverture Places

Islands and names

Charleston Lake contains 152 islands in the Ontario Hydro Network’s outline, eight of them over 10 hectares and 57 under a tenth of a hectare. Eight of them lie inside wetlands mapped in the province’s Wetland With Significance dataset.

The ten largest islands outside a mapped wetland, numbered to the table. Areas are measured on the province’s outline.

The ten largest islands outside a mapped wetland
	Island	Hectares
1	Deer Island	54.1
2	Croziers Island	52.5
3	Democrat Island	38.7
4	Buck Island	33.1
5	Wolf Island	20.4
6	Sheep Island	18.9
7	Fisher Island	18.6
8	Hogback Island	14.3
9	Hedge Hog Island	7.4
10	Hen Island	7.2

Official names

Ontario’s geographic names register lists 173 official names on the water and its islands: 104 islands, 29 bays, two rocks, one narrows and fifteen points on islands. A further 22 named points stand on the mainland shore. The register records the origin of two names.

Bays 29

Black Hole Bay
Dixons Bay
Donaldson Bay
Four Corners Water
Gailies Bay
Gavins Bay
Grassy Bay
Greens Bay
Hay Bay
Huckleberry Hollow Bay
La Rose Bay
Larkin Bay
Loon Bay
Mud Bay
Mud Bay
Nest Bay
Oswego Bay
Runnings Bay
Sallys Hole
Sand Bay
Sapbush Bay
Shad Bay
Slacks Bay
Slim Bay
Sunset Bay
Tallow Rock Bay
Warren Bay
Waterlily Bay
Webster Bay

Shoals and rocks 2

Eagle Rock
Tallow Rock

Harbours, cuts and narrows 1

The Narrows

Points on the shore 22

Angel Point
Blogget Point
Bowsprit Point
Buckhorn Point
Butternut Point
Cedar Grove Point
Crawford Point
Dead Horse Point
Derbyshire Point
Donaldson Point
Greers Point
Jacksons Point
Justus Point
Lone Fisherman Point
Lookout Point
Medoles Point
Peggys Point
Sand Bay Point
Slacks Point
White Birch Point
White Sheep Point
Yardarm Point

Communities on the lake 3

Charleston
Outlet
Beales Mills

Nearby lakes

Red Horse Lake5 km away
Upper Beverley Lake10 km away
Sand Lake19 km away
Newboro Lake25 km away

All lakes

Questions about Charleston Lake

How deep is Charleston Lake?
Its maximum recorded depth is 97.3 meters, determined in Ontario’s 2004 and 2009.
How big is Charleston Lake?
Its surface covers 26.4 square kilometers and it holds 152 islands. Of its 179 kilometers of shoreline, 94 kilometers is the mainland shore and 85 kilometers is the shore of the islands.
What fish are in Charleston Lake?
Ontario’s aquatic resource records name 31 species, among them lake trout, smallmouth bass, largemouth bass, northern pike, lake whitefish and yellow perch.
Is there a public boat launch?
Records mark two marinas on Charleston Lake.

A print of Charleston Lake

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

Ask about a Charleston Lake print

Looking at a property on Charleston 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 figures for Charleston 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 Charleston 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.
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. Survey behind the depths: 2004 and 2009.
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.