Where is Big Stone Lake?

Big Stone Lake is a lake in Roberts County, South Dakota. Its water-quality measurements are published by SD DANR and shown on this page as reported.

Are there boat ramps on Big Stone Lake?

Big Stone Lake has 7 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Rearing Ponds Land Use Area, Kolb Public Water Access, Big Stone Lake #8, Ortonville, Ortonville (North), among others. Public access is listed as yes.

Can I fish at Big Stone Lake?

Big Stone Lake has 7 documented boat landings in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by South Dakota's fish and wildlife agency, so check its current regulations before you go.

Big Stone Lake

Roberts County, South DakotaView map Directions

SD DANR publishes the water-quality measurements for Big Stone Lake. Here is what has been measured.

Clarity

3 ft

Secchi · sampled 2023

Phosphorus

116 µg/L

Typical for South Dakota

Measured by SD DANR

Chlorophyll-a

23.6 µg/L

Typical for South Dakota

Measured by SD DANR

Type

Eutrophic

Trophic class

Eutrophic
Public access

See the measurements Directions Where to stay

Big Stone Lake in Roberts County, South Dakota has water-quality measurements published by SD DANR, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 116 µg/L. Chlorophyll-a (algae): 23.6 µg/L.

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Big Stone Lake is a productive, nutrient-rich eutrophic lake in Roberts County, South Dakota. Limited fish-species data available. Public access is available with 7 public boat landings. Compared to the 3 other monitored lakes in Roberts County, Big Stone Lake ranks #2 for water quality.

Source: EPA Water Quality Portal sampling records, SD DANR, last sampled 2023-08-09. Methodology: how these readings are compared.

Big Stone Lake has 7 public boat landings, so a lakefront rental is not the only way to get a boat on the water. If you are planning to stay, you can search lake houses and cabins around Big Stone Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.

What Big Stone Lake is good for

From access and monitoring records, not editorial picks.

Boat launch7 documented ramps

Swimming conditions

Readings only

Algae risk

Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.

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

Whether Big Stone Lake 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 Big Stone Lake

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

Very murky, less than 3 ft of visibility. Phosphorus 116 µg/L. Chlorophyll-a 23.6 µg/L. TSI 68.

Water quality readings
Measure	Reading	Where it sits
Water clarity (Secchi depth)	3ft	Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer.
Total phosphorus	116µg/L	Poor GoodFairPoor
Chlorophyll-a (algae)	23.6µg/L	Poor GoodFairPoor
Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a.	68	Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic

High nutrients, frequent algae, reduced clarity

Ask about Big Stone Lake

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

Recreation & Access

Boat Landings

Yes

Public Access

Rearing Ponds Land Use AreaPublic
Kolb Public Water AccessPublic
Big Stone Lake #8, OrtonvillePublic
Ortonville (North)Public
Kanne (Highway 34)Public
State Park RoadPublic

Showing 6 of 7 documented landings from the USGS National Boat Ramps inventory.

Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps

Stays via Stay22

Stays near Big Stone Lake

Compare lakeside cabins, hotels, and vacation rentals near Big Stone Lake in Roberts 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Big Stone Lake are listed below.

Top-rated places to stay near Big Stone Lake

Prices for Oct 23–25, 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.

Planning a trip? Cabins and lodging at Big Stone Lake → · more South Dakota lake trips

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Fishing Big Stone Lake

→ Big Stone Lake fishing regulations (limits, seasons, special rules)

Regulated Pollution Sources Nearby

2 EPA-permitted facilities operate within about 5 miles of Big Stone Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.

Lg Everist Inc
Ortonville · 3.1 mi away · NPDES MN0068764
Recent violation
Big Stone City
Big Stone City · 3.8 mi away · NPDES SD0023663

Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.

Nearby Lakes in Roberts County

Bullhead Lake—View →Traverse Lake3.9 ft clear · Eutrophic—View →Mud Lake—View →Lake Bdesaka—View →Mollie Lake—View →Round Lake—View →

Frequently asked questions about Big Stone Lake

Where is Big Stone Lake?: Big Stone Lake is a lake in Roberts 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 Big Stone Lake?: Big Stone Lake in Roberts County, South Dakota has water-quality measurements published by SD DANR, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 116 µg/L. Chlorophyll-a (algae): 23.6 µg/L.
Is Big Stone Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Are there boat ramps on Big Stone Lake?: Big Stone Lake has 7 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Rearing Ponds Land Use Area, Kolb Public Water Access, Big Stone Lake #8, Ortonville, Ortonville (North), among others. Public access is listed as yes.
Can I fish at Big Stone Lake?: Big Stone Lake has 7 documented boat landings in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by South Dakota's fish and wildlife agency, so check its current regulations before you go.

Explore Big Stone Lake across LakeQuality

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Where this data comes from

39 measurements from 2 monitoring stations, 2020–2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

Minnesota Pollution Control Agency - Ambient Surface WaterMNPCA39 samples · 2020–2023

Analytical methods

Field measurement/observation, generic method
Phosphorus by Two Reagent Colorimetry
10200 H ~ Chlorophyll a-b-c Determination

Monitoring station identifiers (2)

EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.