Skip to main content
LakeQuality

Lac Gervais

Matawinie, QuébecView mapDirections

zone de transition méso-eutrophe

This is MELCCFP's own trophic classification for 2025, not a LakeQuality grade. See every year

Clarity
1.4 m
Murkier than most
Secchi · sampled 2025
Phosphorus
21.9 µg/L
More phosphorus than most
Measured by MELCCFP
Chlorophyll-a
12.9 µg/L
More algae than most
Measured by MELCCFP

Lac Gervais in Matawinie, Québec is classified zone de transition méso-eutrophe by Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs (Québec) for 2025. Water clarity: 1.4 m visibility. Phosphorus: 21.9 µg/L. Chlorophyll-a (algae): 12.9 µg/L.

Loading map…

Lac Gervais is a lake in Matawinie County, Québec.

Source: Québec RSVL (MELCCFP) — not the EPA Water Quality Portal, last sampled 2025-08-01. Methodology: how these readings are compared.

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Lac Gervais is safe to swim in today is a call for le Ministère de l'Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

Get alerts for Lac Gervais →

Water quality measurements for Lac Gervais

These are the measurements MELCCFP publishes for Lac Gervais, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

Murky, only visible to about 4.6 ft. Phosphorus 21.9 µg/L. Chlorophyll-a 12.9 µg/L.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)1.4mMeasured, not scored

How deep a black-and-white disk stays visible from the surface. Higher is clearer.

Total phosphorus21.9µg/LMeasured, not scored

The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential.

Chlorophyll-a (algae)12.9µg/LMeasured, not scored

The green pigment in algae — a direct measure of how much algae is in the water.

Ask about Lac Gervais

Answers come straight from the public measurements and survey records on this page.

Stays via Stay22

Stays near Lac Gervais

Compare lakeside cabins, hotels, and vacation rentals near Lac Gervais in Matawinie, Québec — 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 Lac Gervais

Prices for Oct 30–Nov 1, 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 Lac Gervais’s readings

Email me when new measurements post for this lake. Updates stay free.


Or email

Fishing Lac Gervais

Nearby Lakes in Matawinie

Frequently asked questions about Lac Gervais

Where is Lac Gervais?

Lac Gervais is a lake in Matawinie, Québec. MELCCFP classifies it zone de transition méso-eutrophe for 2025. This is MELCCFP's own trophic classification for 2025, not a LakeQuality grade.

What is the water quality of Lac Gervais?

Lac Gervais in Matawinie, Québec is classified zone de transition méso-eutrophe by Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs (Québec) for 2025. Water clarity: 1.4 m visibility. Phosphorus: 21.9 µg/L. Chlorophyll-a (algae): 12.9 µg/L.

Measurements on this page ↑

Is Lac Gervais safe to swim in?

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Swimming on this page ↑

The authority’s own classification

Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs (Québec) publishes its own classification for Lac Gervais. It is shown here as theirs, in their words, and is not folded into the LakeQuality letter.

Most recent, 2025
zone de transition méso-eutrophe

This is MELCCFP's own trophic classification for 2025, not a LakeQuality grade.

A trophic class ranks how nutrient-rich a lake is, from oligotrophic at the low end to eutrophic at the high end. It describes nutrients and plant growth, not bacteria, and it is not a swimming clearance.

Earlier years (2 classified 2024–2025)
YearPublished class
2024zone de transition méso-eutrophe

Published by Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs (Québec). A classification is not a same-day swimming clearance. See data sources.

Where this data comes from

Measurements for Lac Gervais come from the Réseau de surveillance volontaire des lacs (RSVL), not the EPA Water Quality Portal. Per-sample source details are not recorded for this lake. MELCCFP RSVL (CC BY 4.0). See data sources.