Longline Lake
Muskoka District, OntarioView mapDirections
Ontario MECP publishes the water-quality measurements for Longline Lake. Here is what has been measured.
- 46 ft max depth
Longline Lake in Muskoka District, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 3 m visibility. Phosphorus: 17.6 µg/L.
Stays via Stay22
Stays near Longline Lake
Compare lakeside cabins, hotels, and vacation rentals near Longline Lake in Muskoka District, Ontario — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Longline Lake
Prices for Sep 18–20, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Follow Longline Lake’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Longline Lake is a lake in Muskoka District County, Ontario with an estimated average depth of about 46 feet.
Source: Ontario open-data programmes (Lake Partner Program and Broad-scale Monitoring) — not the EPA Water Quality Portal, last sampled 2002-05-15. Grade methodology: LakeQuality methodology.
What Longline Lake is good for
From access and monitoring records, not editorial picks.
- Clear water9.8 ft of visibility
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Longline Lake is safe to swim in today is a call for the Ontario Ministry of the Environment, Conservation and Parks and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Longline Lake
These are the measurements Ontario MECP publishes for Longline Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 9.8 ft. Phosphorus 17.6 µg/L. TSI 45.
| Metric | Value | EPA condition class |
|---|---|---|
| Water Clarity (Secchi Depth) | 3 m | Measured, not scored |
| Phosphorus | 17.6 µg/L | Measured, not scored |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 45 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~14 m est. |
| Average Depth | ~4.6 m est. |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Ontario has not published bathymetry for Longline Lake.
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Fishing Longline Lake
Nearby Lakes in Muskoka District
Frequently asked questions about Longline Lake
Ask about Longline Lake
Answers come straight from the public measurements and survey records on this page.
Where is Longline Lake?
- Longline Lake is a lake in Muskoka District, Ontario. Its water-quality measurements are published by Ontario MECP and shown on this page as reported.
What is the water quality of Longline Lake?
- Longline Lake in Muskoka District, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 3 m visibility. Phosphorus: 17.6 µg/L.
Is Longline Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Longline Lake?
- No published bathymetric survey covers Longline Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 46 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Explore Longline Lake across LakeQuality
More lakes in Ontario
Other Lakes in Ontario
Mesotrophic Lakes in Ontario
Where this data comes from
Measurements for Longline Lake come from Ontario open-data programmes (Lake Partner Program and Broad-scale Monitoring), not the EPA Water Quality Portal. Per-sample source details are not recorded for this lake. Contains information licensed under the Open Government Licence – Ontario. See data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)