Fern Lake

Algoma District, Ontario · MNRF bathymetric survey

42m Mapped depth
138 ft

94 ha 42 contours Fishing access

Paddling Index80Very Goodaway from major roads · wooded shoreline · sheltered geometry

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Depth scale

0191725334142 m

The lake

Survey readout

Fern Lake is mapped to a depth of 42 m (138 ft) on the Ontario MNRF survey and covers about 94 ha (232 acres) in Algoma District, Ontario. Depths come from the Ontario MNRF survey of 2022.

Measured from the Ontario MNRF bathymetry survey.

Deepest mapped contour: 42 m (138 ft)
Survey year: 2022
Surface area: 94 ha (232 acres)
Shoreline: 6.9 km (4.3 mi) · irregular
Fishing access: 1 MNRF fishing access point · 1 shoreline access site

Additional depth details42 contours

Contour depths: 0–42 m (138 ft)
Deep-spot markers: 42 m (138 ft)

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Location

Algoma District, Ontario · 15 nearest of 687 lakes and 1 river · tap a dot to open it

Chart data

Provenance

Sources: Ontario MNRF / LIO Bathymetry, Ontario FRI Leaf-On Imagery, Ontario FRI LiDAR DTM, OpenStreetMap (ODbL), Contains information licensed under the Open Government Licence – Ontario.

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Map details & sources5 sources

All layers registered to one bounding box; positions in WGS 84.

Survey-derived depth contours drape over Ontario LiDAR (FRI DTM) elevation, with a Ontario FRI aerial basemap and OpenStreetMap shoreline. Colour shows surveyed depth; dark lines are the survey's own isobaths.

Coordinates: 46.73561, -83.86304
MNRF lake ID: 17-2815-51794
Vertical exaggeration: 1.4×
Basemap: Ontario FRI
Model size: 1.4 MB

Check the source: this lake’s record (17-2815-51794) in the Ontario MNRF bathymetry index, and the contour line layer the map is drawn from (Land Information Ontario open data, Open Government Licence – Ontario). Survey year: 2022. This model was built 2026-09-08. Depths between contours are interpolated, not measured.

Paddling

Paddling Index methodology v1.0 · calculated 2026-09-16

80 / 100Very GoodData confidence: High

Fern Lake has a heavily wooded and largely undeveloped setting, generally sheltered geometry, little nearby major-road exposure.

Why this score?5 components

Included in the index

Component	Rating	Points of weight	Measurement
Natural setting	Excellent	34.9 of 35	99% natural land cover within 150 m of shore (90% forest, 1% wetland; 1% developed)
Geometric wind exposure	Very Good	17.9 of 29	mean fetch 1,042 m · 3% of sampled water within 500 m of shelter · generally short fetch
Motor & speed rules	Not modelled	—	Canada publishes vessel motor and speed restrictions as federal legal schedules, not map data, so they are not part of the Ontario index. Check local signage and Transport Canada rules before going out.
Public access	Good	12.3 of 18	1 MNRF fishing access point · shoreline access
Road isolation	Excellent	14.9 of 18	relatively isolated from major roads · 6 Ontario Road Network segments within 1.2 km (traffic estimated from road class, not measured)

Additional paddling considerations

These describe the lake but are not part of the v1 Paddling Index and do not change the number above.

Wake sensitivity: Low — wide enough that wakes disperse over most of the lake
Observed motorized activity: Unknown — No lake-level measurement of boat traffic is available. Legal permission to operate motors is not evidence of use.
Wildlife habitat potential: High — 90% forest and 1% wetland cover within 150 m of shore
Mapped wildlife habitat: Mapped — Ontario MNRF has mapped moose aquatic feeding areas within 1 km of this lake. These are habitat records from provincial surveys, not animal counts; areas with nothing mapped may still hold wildlife. · Ontario MNRF Wildlife Values Area. Contains information licensed under the Open Government Licence – Ontario.

Compare Ontario lakes by Paddling Index →

How this index is calculated. The Paddling Index is a relative composite derived from lake geometry and public land-cover, access and road-network data. It is not a user review, a safety rating, or a prediction of an individual outing. Differences of a few points should not be treated as meaningful — an 84 and an 82 are broadly comparable. Components and weights for Ontario lakes: natural setting 35%, geometric wind exposure 29%, public access 18%, road isolation 18%. Motor and speed restrictions are not modelled for Ontario, and road traffic is estimated from road class, not measured. Where a component has no data the remaining weights are renormalized and the confidence rating is lowered; below Medium confidence no number is shown. Ontario scores are relative to other Ontario lakes and are not directly comparable with Paddling Index scores on our sister sites, which use different data sources and include a watercraft-rules component. Sources: Ontario MNRF bathymetry outline (0 m contour or survey index polygon), Ontario Land Cover v1.0, Ontario MNRF (Open Government Licence – Ontario) (2020), Ontario MNRF Fishing Access Points (Open Government Licence – Ontario) (2026-09) and Ontario Road Network (Open Government Licence – Ontario); traffic estimated by road class, not measured (2026-09). Conditions change quickly — check current weather and local conditions before going out.

Angler catch reports

Fish ON-Line · 2020–2023

3 angler trips logged here between July 2020 and July 2023 — too few to show a pattern, so each species is listed with how many trips named it.

Lake Trout

Pictures are sized relative to each other. Illustrations are AI-generated representative adults in everyday colours, not photographs (provenance).

Lake Trout3 of 3 trips · 11 caught

About these fish → the Fish of Ontario guide

Trips are logged voluntarily by anglers in Ontario’s Fish ON-Line app. This is what people report catching, not a Ministry survey, and a species nobody has logged may still be here. Contains information licensed under the Open Government Licence – Ontario. Source: Ontario Ministry of Natural Resources, Fish ON-Line. A logged catch does not mean it is legal to catch or keep: check the Ontario Fishing Regulations Summary for this lake’s zone and exceptions.

Quick answers

Fern Lake — common questions

How deep is Fern Lake?

The deepest contour on the Ontario MNRF bathymetric survey of Fern Lake is 42 m (138 ft). That is the deepest depth the historical survey map records, which may differ from the deepest point of the lake itself.

How big is Fern Lake?

Fern Lake covers about 94 ha (232 acres) in Algoma District, Ontario.

Is there public access to Fern Lake?

The Ontario MNRF lists 1 fishing access point within 100 m of the shoreline of Fern Lake: 1 shoreline access site. Recorded ownership: 1 provincial. The list includes municipal and privately owned sites, and some may charge a fee or restrict parking, so it confirms a place anglers use rather than a public right of way. Check locally before you go.

More lakes in Algoma District