Where is Thompson Falls Reservoir?

Thompson Falls Reservoir is a lake in Sanders County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.

Are there boat ramps on Thompson Falls Reservoir?

Thompson Falls Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Thompson Falls. Public access is listed as yes.

Can I fish at Thompson Falls Reservoir?

Thompson Falls Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Montana's fish and wildlife agency, so check its current regulations before you go.

Are there campgrounds on Thompson Falls Reservoir?

Thompson Falls Reservoir has 1 public campground from USGS The National Map within 5 km, including Gold Rush Cg / Trhd. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.

Thompson Falls Reservoir

Sanders County, Montana211 acresView map Directions

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

Area

211 acres

Surface area

Shoreline

4 mi

Measured length

Public access

See the measurements Directions Where to stay

Thompson Falls Reservoir in Sanders County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 211 acres.

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Thompson Falls Reservoir is a 211-acre lake in Sanders County, Montana. Limited fish-species data available. Public access is available with 1 public boat landing.

Source: EPA Water Quality Portal sampling records, Montana DEQ. Methodology: how these readings are compared.

What Thompson Falls Reservoir is good for

From access and monitoring records, not editorial picks.

Boat launch1 documented ramp
Camping1 public campground nearby

Swimming conditions

No reading

Not rated

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

Whether Thompson Falls Reservoir is safe to swim in today is a call for the Montana 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 Thompson Falls Reservoir

These are the measurements Montana DEQ publishes for Thompson Falls Reservoir, 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 Thompson Falls Reservoir

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

Lake Details

Surface area

211 acres

Shoreline

4 mi

Public access

Yes

Listed by Montana DEQ

No bathymetric survey has been published for Thompson Falls Reservoir, so its depth is not documented here.

Recreation & Access

Boat Landings

Yes

Public Access

Campgrounds

Thompson FallsPublic

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

Public campgrounds near Thompson Falls Reservoir

Gold Rush Cg / Trhd1.6 km

Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes

Stays via Stay22

Stays near Thompson Falls Reservoir

Compare lakeside cabins, hotels, and vacation rentals near Thompson Falls Reservoir in Sanders County, Montana — 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 Thompson Falls Reservoir

Prices for Oct 16–18, 4 adults. Change dates on the map below.

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Fishing Thompson Falls Reservoir

→ Thompson Falls Reservoir fishing regulations (limits, seasons, special rules)

Nearby Lakes in Sanders County

Noxon Reservoir14.6 miView →Fishtrap Lake20.2 miView →Wanless Lake31.4 miView →Lower Thompson Lake—View →Rock Lake—View →Rainbow Lake27.1 miView →

Frequently asked questions about Thompson Falls Reservoir

Where is Thompson Falls Reservoir?: Thompson Falls Reservoir is a lake in Sanders County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Thompson Falls Reservoir?: Thompson Falls Reservoir in Sanders County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 211 acres.
Is Thompson Falls Reservoir safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Are there boat ramps on Thompson Falls Reservoir?: Thompson Falls Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Thompson Falls. Public access is listed as yes.
Can I fish at Thompson Falls Reservoir?: Thompson Falls Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Montana's fish and wildlife agency, so check its current regulations before you go.
Are there campgrounds on Thompson Falls Reservoir?: Thompson Falls Reservoir has 1 public campground from USGS The National Map within 5 km, including Gold Rush Cg / Trhd. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.