Olsen Slough
Nelson County, North Dakota355 acresView mapDirections
No nutrient or algae sampling on record from ND DEQ for this lake.
Olsen Slough in Nelson County, North Dakota has water-quality measurements published by ND DEQ, shown here as reported. Surface area: 355 acres.
Olsen Slough is a 355-acre lake in Nelson County, North Dakota.
Source: EPA Water Quality Portal sampling records, NDDEQ. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Olsen Slough is safe to swim in today is a call for the North Dakota Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Olsen Slough
These are the measurements ND DEQ publishes for Olsen 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 Olsen Slough
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
355 acres
Shoreline
5.2 mi
No bathymetric survey has been published for Olsen Slough, so its depth is not documented here.
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Fishing Olsen Slough
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Frequently asked questions about Olsen Slough
Where is Olsen Slough?
- Olsen Slough is a lake in Nelson County, North Dakota. Its water-quality measurements are published by ND DEQ and shown on this page as reported.
What is the water quality of Olsen Slough?
- Olsen Slough in Nelson County, North Dakota has water-quality measurements published by ND DEQ, shown here as reported. Surface area: 355 acres.
Is Olsen Slough safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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Where this data comes from
Measurements for Olsen Slough come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Depth, fish, and access data from North Dakota Game & Fish