Where is Grassy Lake?

Grassy Lake is a lake in St. Martin County, Louisiana. Its water-quality measurements are published by LDEQ and shown on this page as reported.

How deep is Grassy Lake?

Grassy Lake has a maximum depth of 8.9 feet and an average depth of 5.9 feet. The lake covers 1241 acres.

Grassy Lake

St. Martin County, Louisiana1,241 acresView map Directions

No nutrient or algae sampling on record from LDEQ for this lake.

Max depth

8.9 ft

Bathymetric survey

Area

1,241 acres

Surface area

Shoreline

10.7 mi

Measured length

9 ft max depth

See the measurements Directions Where to stay

Grassy Lake in St. Martin County, Louisiana has water-quality measurements published by LDEQ, shown here as reported. Maximum depth: 8.9 ft. Surface area: 1241 acres.

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Grassy Lake is a 1,241-acre lake in St. Martin County, Louisiana with a maximum depth of 9 feet (6-foot average).

Source: EPA Water Quality Portal sampling records, your state environmental agency. Methodology: how these readings are compared.

What Grassy Lake is good for

From access and monitoring records, not editorial picks.

Big water1,241 acres

Swimming conditions

No reading

Not rated

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

Whether Grassy Lake is safe to swim in today is a call for the Louisiana Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Grassy Lake

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

No clarity data. TSI undefined.

Ask about Grassy Lake

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

Lake Details

Max depth

8.9 ft

Average depth

5.9 ft

Surface area

1,241 acres

Shoreline

10.7 mi

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Stays near Grassy Lake

Compare lakeside cabins, hotels, and vacation rentals near Grassy Lake in St. Martin County, Louisiana — 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 Grassy Lake

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Fishing Grassy Lake

→ Grassy Lake fishing regulations (limits, seasons, special rules)

Nearby Lakes in St. Martin County

Duck Lake—View →Boutte Cove—View →Crossing Cove—View →Jackass Bay—View →Haha Bay—View →Bay Baron—View →

Frequently asked questions about Grassy Lake

Where is Grassy Lake?: Grassy Lake is a lake in St. Martin County, Louisiana. Its water-quality measurements are published by LDEQ and shown on this page as reported.
What is the water quality of Grassy Lake?: Grassy Lake in St. Martin County, Louisiana has water-quality measurements published by LDEQ, shown here as reported. Maximum depth: 8.9 ft. Surface area: 1241 acres.
Is Grassy Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Grassy Lake?: Grassy Lake has a maximum depth of 8.9 feet and an average depth of 5.9 feet. The lake covers 1241 acres.