Canada Fly Guide
Rivers & Lakes · Stillwater

St. Mary Lake

A stillwater in the St. Mary River watershed, Expansion of St. Mary River, ~343 ha surface area, holding Burbot and Westslope (Yellowstone) Cutthroat Trout.
Updated July 30, 2026

Wildfire & Access

BC Wildfire Service · live around St. Mary Lake
connecting… Live feed

Checking wildfire conditions…

Live on refresh · BC Wildfire Service map · EmergencyInfoBC — always confirm orders and bans before travelling.

St. Mary Lake is a stillwater in the St. Mary River watershed, Expansion of St. Mary River. ~343 ha surface area.

The water

St. Mary Lake lies Expansion of St. Mary River; in the St. Mary River watershed. It covers ~343 ha surface area. The lake survey puts it at max 21 m, mean 7.7 m, which sets the depth you fish.

The fishing

St. Mary Lake fishes on classic stillwater lines: chironomids over the shoals, leech and attractor retrieves along the drop-offs, and depth or troll work to the shoal-and-drop-off structure. Match the season and confirm against a local report.

waves
Stillwater
St. Mary River watershed
straighten
343 ha
surface area
water
max 21 m, mean 7.7 m
lake survey
set_meal
Burbot and Westslope (Yellowstone) Cutthroat Trout
recorded

Conditions

  • Depth: max 21 m, mean 7.7 m (BC lake survey 1959-06-15).
  • Water-health signal: excellent (health index 60), 9 species over 67 observations.

Access & the rules

Confirm the launch, parking and any motor/float or seasonal restrictions for St. Mary Lake locally before you commit a day; the map shows where the lake sits in its drainage.

gavel

Before you fish

Confirm the current BC freshwater fishing regulations (Region 4 – Kootenay) before you go. Official synopsis: gov.bc.ca fishing regulations.