Where is Mortimer Slough?

Mortimer Slough is a lake in Brookings County, South Dakota. Its water-quality measurements are published by SD DANR and shown on this page as reported.

Mortimer Slough

Brookings County, South Dakota139 acresView map Directions

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

Area

139 acres

Surface area

Shoreline

3.7 mi

Measured length

See the measurements Directions Where to stay

Mortimer Slough in Brookings County, South Dakota has water-quality measurements published by SD DANR, shown here as reported. Surface area: 139 acres.

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Mortimer Slough is a 139-acre lake in Brookings County, South Dakota.

Source: EPA Water Quality Portal sampling records, SD DANR. 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 Mortimer Slough is safe to swim in today is a call for the South Dakota Department of Agriculture and Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Mortimer Slough

These are the measurements SD DANR publishes for Mortimer Slough, 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 Mortimer Slough

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

Lake Details

Surface area

139 acres

Shoreline

3.7 mi

No bathymetric survey has been published for Mortimer Slough, so its depth is not documented here.

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Stays near Mortimer Slough

Compare lakeside cabins, hotels, and vacation rentals near Mortimer Slough in Brookings County, South Dakota — 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 Mortimer Slough

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Fishing Mortimer Slough

→ Mortimer Slough fishing regulations (limits, seasons, special rules)

Nearby Lakes in Brookings County

Moe Slough1.3 miView →Lake Mitchell5.1 miView →Brush Lake—View →Lake Sinai—View →Nelson Slough—View →Pederson Slough—View →

Frequently asked questions about Mortimer Slough

Where is Mortimer Slough?: Mortimer Slough is a lake in Brookings County, South Dakota. Its water-quality measurements are published by SD DANR and shown on this page as reported.
What is the water quality of Mortimer Slough?: Mortimer Slough in Brookings County, South Dakota has water-quality measurements published by SD DANR, shown here as reported. Surface area: 139 acres.
Is Mortimer Slough safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.