Brennan Lake Depth Map & Fishing Spots (Thunder Bay District, ON)

Recommendations come from depth structure and seasonal species behavior. Treat them as a starting point, not a guarantee. Contours here are interpolated from real agency depth surveys (state DNR / USACE). Never use for navigation. Always check local regulations.

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Recent catches at Brennan Lake

Shared by DepthScout anglers. Exact spots stay private, always.

No shared catches here yet — be the first.Log a catch from the map above and share it to put Brennan Lake on the board.

Fishing Brennan Lake: what the data says

5,914-acre lake in Thunder Bay District, Ontario. The lake tops out around 66 ft. The depth data here comes from the Ontario MNRF survey of 1980 (a transect sounding survey). The exact depth survey is published on its own because no defensible water-specific species roster was found.

Brennan Lake maps at 5,942 acres behind 152.3 miles of shoreline — 193 islands included. With a shoreline index of 14.1, this water is all arms and coves — edge habitat well beyond its acreage. Roughly 90% of the water is 15 ft or less, the band where the food chain lives. The basin spans about 12.2 mi end to end and 5.1 mi across at its widest. It sits in Thunder Bay District. Its nearest charted neighbour, Change Lake, is 4 mi to the south.

Notable structure

Count 15 structure marks on this chart. The deepest, Deep basin, sits near 45 ft.

Deep basin: deep basin, around 45 ft
Shallow feeding flat: feeding flat, around 19 ft
Sharp break: drop-off, around 17 ft
Shallow feeding flat: feeding flat, around 15 ft
Main-lake point: point, around 11 ft
Sharp break: drop-off, around 10 ft
Sharp break: drop-off, around 6 ft
Shoreline point: point, around 6 ft
Secondary point: point, around 4 ft
Break off the point: drop-off, around 3 ft
Rock reef: rock pile, around 3 ft
Shallow bay flat: weed flat, around 2 ft
Back-bay flat: weed flat, around 2 ft
Rock reef: rock pile, around 2 ft

Brennan Lake fishing regulations

Season dates, license requirements, and size and bag limits for Ontario waters are set by the Ontario fishing regulations (FMZ summary) — and special regulations can apply to Brennan Lake specifically, so confirm the current rules before you fish.

Check the official Ontario fishing regulations →

Common questions

How deep is Brennan Lake?

Brennan Lake is about 66 ft (20 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1980 (a transect sounding survey).

What fish are in Brennan Lake?

No official water-specific fish survey, inspected stocking record, reported-catch roster, or species-bearing fisheries classification was found for Brennan Lake. Its depth chart is still a real survey; species and fishing spots are intentionally left unclaimed.

What are the fishing regulations for Brennan Lake?

Fishing on Brennan Lake is regulated by the Ontario fishing regulations (FMZ summary). Check the official Ontario regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.

Nearby waters

Change Lake 4 mi · Dagger Lake 5 mi · Granite Lake 8 mi · McWade Lake 11 mi · Berry Lake 13 mi · Sassenach Lake 14 mi · Redhead Lake 14 mi · Hillside Lake 15 mi · Painter L. 15 mi · Elga L. 16 mi · Ranger Lake 16 mi · Surprise Lake 18 mi

More water nearby: Thunder Bay District fishing maps (662 charts). Browse all Ontario fishing maps or see every water on DepthScout. Bathymetry credit: state fisheries survey programs. How we build these maps. Fish here with a sonar unit that logs? Send us your depth data and we'll improve this chart, credited to you. For fishing guidance only, never navigation.