LakeScout
Satellite view of Lac Saint-Louis

Lac Saint-Louis

Higher than usual

Water level is higher than usual for mid-September and falling.

Low (20.13m)Normal rangeHigh (21.78m)

Current Weather

2d ago
16°CMostly Cloudy
Wind NW 4 km/h
Humidity 67%

Chance of showers

Environment Canada — Metro Montréal - Laval

vs. Last Year

No data available

7-Day Trend

Falling

Down 5.0 cm over the past week

-5.0 cm over 7 days

Seasonal Position

81st percentile

Based on 109 years of records

Seasonal Outlook

Typical next 7 days

This lake usually drops slightly over the next week.

Typical next 14 days

Over two weeks, levels typically drops moderately.

Tracking

This year is moving slower than usual.

Based on 109 years of seasonal patterns. This is a historical seasonal pattern, not a forecast.

Fish Consumption Advisories (8 species)

The following consumption advisories are in effect for fish caught in Lac Saint-Louis.

Achigan
ContaminantSizeGeneral pop.Sensitive pop.
Mercure25–30 cm8/month
Mercure30–35 cm8/month
Mercure35+ cm4/month
Barbotte brune
ContaminantSizeGeneral pop.Sensitive pop.
Mercure25–30 cm8/month
Mercure30+ cm8/month
Mercure20–25 cm8/month
Barbue de rivière
ContaminantSizeGeneral pop.Sensitive pop.
Mercure45–50 cm4/month
Mercure40–45 cm8/month
Mercure50+ cm8/month
Doré jaune
ContaminantSizeGeneral pop.Sensitive pop.
Mercure50+ cm2/month
Mercure30–40 cm8/month
Mercure40–50 cm8/month
Grand brochet
ContaminantSizeGeneral pop.Sensitive pop.
Mercure40–55 cm8/month
Mercure55–70 cm4/month
Mercure70+ cm4/month
Meunier noir
ContaminantSizeGeneral pop.Sensitive pop.
Mercure30–35 cm8/month
Mercure40+ cm8/month
Mercure35–40 cm8/month
Perchaude
ContaminantSizeGeneral pop.Sensitive pop.
Mercure20–25 cm8/month
Mercure25+ cm8/month
Mercure15–20 cm8/month
Tanche
ContaminantSizeGeneral pop.Sensitive pop.
Mercure30–40 cm8/month
Mercure40–50 cm8/month
Source: Guide de consommation du poisson (MELCCFP) (2025). Advisory data is updated annually.

Water Level — Last 30 Days

Technical details
Current level
21.33 m
Reference value
21.33 m (rolling_6h_mean)
Percentile for date
81st percentile
Years of record
109
Source station
SAINT-LOUIS (LAC) A POINTE-CLAIRE (02OA039)
Est. average depth
Relationship type
direct_lake
Mapping confidence
medium
Today's normal range
20.71–21.23 m
Same-date historical range
20.13–21.78 m
30-day change
+13.7 cm
Data confidence
medium
Observed at
Sep 20, 2026
Last snapshot
Sep 20, 2026

Data source: ECCC Water Office — Station 02OA039. Water level readings are provisional and subject to revision. This is not a navigation or flood-warning service.