Lake Rosseau

Normal

Water level is right where you'd expect for mid-September and falling.

Low (8.72m)Normal rangeHigh (9.09m)

Current Weather

2d ago

19°CMainly Sunny

Wind N 9 km/h

Humidity 54%

A mix of sun and cloud

Environment Canada — Parry Sound - Muskoka

vs. Last Year

No data available

7-Day Trend

↓Falling

Down 4.6 cm over the past week

-4.6 cm over 7 days

Seasonal Position

53rd percentile

Based on 22 years of records

Seasonal Outlook

Typical next 7 days

This lake usually holds steady over the next week.

Typical next 14 days

Over two weeks, levels typically drops slightly.

Tracking

This year is moving slower than usual.

Based on 22 years of seasonal patterns. Moderate historical coverage. 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 Lake Rosseau.

⚠Burbot (Ling)

Contaminant	Size	General pop.	Sensitive pop.
Mercury	40-45 cm	4/month	Do not eat
Mercury	35-40 cm	8/month	Do not eat
Mercury	65-70 cm	2/month	Do not eat
Mercury	60-65 cm	2/month	Do not eat
Mercury	55-60 cm	4/month	Do not eat
Mercury	50-55 cm	4/month	Do not eat
Mercury	45-50 cm	4/month	Do not eat

⚠Cisco (Lake Herring)

Contaminant	Size	General pop.	Sensitive pop.
	15-20 cm	32/month	—
	20-25 cm	32/month	—
Mercury	25-30 cm	8/month	4/month
Mercury	30-35 cm	8/month	Do not eat
Mercury	35-40 cm	4/month	Do not eat
Mercury	40-45 cm	4/month	Do not eat
Mercury	15-20 cm	—	16/month
Mercury	20-25 cm	—	16/month

⚠Lake Trout

Contaminant	Size	General pop.	Sensitive pop.
Mercury	20-25 cm	16/month	4/month
Mercury	25-30 cm	12/month	4/month
Mercury	30-35 cm	12/month	4/month
Mercury	35-40 cm	8/month	4/month
Mercury	40-45 cm	4/month	Do not eat
Mercury	45-50 cm	4/month	Do not eat
Mercury	50-55 cm	4/month	Do not eat
Mercury	55-60 cm	4/month	Do not eat
Mercury	70-75 cm	2/month	Do not eat
Mercury	>75 cm	Do not eat	—
Mercury	60-65 cm	—	Do not eat
Mercury	65-70 cm	—	Do not eat
Mercury, PCB	65-70 cm	4/month	—
Mercury, PCB	60-65 cm	4/month	—
Mercury, PCB	>75 cm	—	Do not eat

Lake Whitefish

Contaminant	Size	General pop.	Sensitive pop.
	30-35 cm	32/month	—
Mercury	35-40 cm	—	12/month
Mercury	40-45 cm	—	12/month
Mercury	55-60 cm	—	8/month
Mercury	65-70 cm	—	8/month
Mercury	50-55 cm	—	8/month
Mercury	45-50 cm	—	12/month
Mercury	60-65 cm	—	8/month
Mercury	30-35 cm	—	12/month
Mercury, PCB	65-70 cm	16/month	—
Mercury, PCB	55-60 cm	16/month	—
Mercury, PCB	50-55 cm	16/month	—
Mercury, PCB	60-65 cm	16/month	—
PCB	40-45 cm	16/month	—
PCB	45-50 cm	16/month	—
PCB	35-40 cm	16/month	—

⚠Northern Pike

Contaminant	Size	General pop.	Sensitive pop.
Mercury	65-70 cm	8/month	4/month
Mercury	55-60 cm	12/month	4/month
Mercury	60-65 cm	12/month	4/month
Mercury	70-75 cm	8/month	4/month
Mercury	>75 cm	4/month	Do not eat

Rock Bass

Contaminant	Size	General pop.	Sensitive pop.
Mercury	15-20 cm	12/month	4/month
Mercury	20-25 cm	8/month	4/month

⚠Smallmouth Bass

Contaminant	Size	General pop.	Sensitive pop.
	15-20 cm	32/month	—
	20-25 cm	32/month	—
Mercury	25-30 cm	16/month	4/month
Mercury	30-35 cm	8/month	4/month
Mercury	35-40 cm	4/month	Do not eat
Mercury	40-45 cm	4/month	Do not eat
Mercury	45-50 cm	2/month	Do not eat
Mercury	15-20 cm	—	16/month
Mercury	20-25 cm	—	12/month

Walleye

Contaminant	Size	General pop.	Sensitive pop.
Mercury	35-40 cm	16/month	4/month
Mercury	40-45 cm	12/month	4/month
Mercury	45-50 cm	12/month	4/month
Mercury	50-55 cm	8/month	4/month

Source: Guide to Eating Ontario Fish (2025). Advisory data is updated annually.

Lake Profile

Est. average depth28.1 m

Estimated from HydroLAKES v1.0 (Messager et al., 2016). Modeled geo-statistical estimate, not a direct survey measurement.

Boat Launches (12)

Lake Muskoka - West St., Port Carling

0.5 kmMunicipal

Map ↗

Lake Muskoka - Bailey Street, Port Carling

0.7 kmMunicipalParking

Map ↗

Lake Rosseau - Adams Bay

1.2 kmMunicipalParking

Map ↗

Lake Joseph - Port Sandfield

3.6 kmPrivateParking

Map ↗

Brandy Lake

3.7 kmMunicipalParking

Map ↗

Lake Joseph - Appian Way

4.4 kmMunicipalParking

Map ↗

Lake Rosseau - Portage Bay

6.5 kmMunicipal

Map ↗

Church Dock Road, Milford Bay, Lake Muskoka

7.2 kmMunicipalParking

8.3 kmPrivateParking

8.6 kmPrivateParking

Lake Muskoka - Milford Bay

8.7 kmMunicipalParking

Map ↗

Three Mile Lake

9.9 kmMunicipalParking

Map ↗

Source: Ontario MNR Fishing Access Points. Verify conditions before visiting.

Water Level — Last 30 Days

Technical details

Current level: 8.86 m
Reference value: 8.86 m (rolling_6h_mean)
Percentile for date: 53rd percentile
Years of record: 22
Source station: LAKE ROSSEAU AT PORT CARLING (02EB020)
Est. average depth: 28.1 m
Relationship type: direct_lake
Mapping confidence: medium
Today's normal range: 8.81–8.89 m
Same-date historical range: 8.72–9.09 m
30-day change: -0.9 cm
Data confidence: medium
Observed at: Sep 20, 2026
Last snapshot: Sep 20, 2026

Data source: ECCC Water Office — Station 02EB020. Water level readings are provisional and subject to revision. This is not a navigation or flood-warning service.