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LakeQuality

Glen Lake

Lincoln County, Montana300 acresView mapDirections

Montana DEQ publishes the water-quality measurements for Glen Lake. Here is what has been measured.

Clarity
19.9 ft
Clearer than most
Secchi · sampled 2023
Area
300 acres
Surface area
Trend
Worsening
12 years of samples
  • Public access
  • Limited data

Glen Lake in Lincoln County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Water clarity: 19.9 ft visibility. Surface area: 300 acres.

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Glen Lake is a 300-acre lake in Lincoln County, Montana. Overall water quality is declining over recent sampling years. Limited fish-species data available. Public access is available with 1 public boat landing.

Source: EPA Water Quality Portal sampling records, Montana DEQ, last sampled 2023-07-24. Methodology: how these readings are compared.

What Glen Lake is good for

From access and monitoring records, not editorial picks.

  • Clear water19.9 ft of visibility
  • Boat launch1 documented ramp

Swimming conditions

No reading

Limited data

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

Whether Glen Lake 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 Glen Lake

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

Crystal clear, you can see 19.9 ft down. TSI 34.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)19.9ftMeasured, not scored

How deep a black-and-white disk stays visible from the surface. Higher is clearer.

Total phosphorusNo reading

The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential.

Chlorophyll-a (algae)No reading

The green pigment in algae — a direct measure of how much algae is in the water.

Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a.34Oligotrophic
OligotrophicMesotrophicEutrophicHypereutrophic

Low nutrients, clear water. No reading is a swimming clearance.

Ask about Glen Lake

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

Lake Details

Surface area

300 acres

Public access

Yes

Listed by Montana DEQ

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

Recreation & Access

1
Boat Landings
Yes
Public Access
  • Glen LakePublic

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

Stays via Stay22

Stays near Glen Lake

Compare lakeside cabins, hotels, and vacation rentals near Glen Lake in Lincoln 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 Glen Lake

Prices for Oct 30–Nov 1, 4 adults. Change dates on the map below.

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Planning a trip? Cabins and lodging at Glen Lake → · more Montana lake trips

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Fishing Glen Lake

Based on 12 years of monitoring (2012–2023).

  • Water clarity

    Worsening

    3 years

  • Phosphorus

    Worsening

    +0.21 µg/L/yr11 years

  • Chlorophyll-a

    Improving

    -0.05 µg/L/yr12 years

See year-by-year chart →

Reservoir Info (USACE NID)

Glen Lake is a man-made reservoir impounded by the Glen Lake (completed 1950), built primarily for irrigation on the Lick Creek; earth-type dam, 14 ft tall and 700 ft long.

Surface area
300 ac
Normal storage
2,660 ac-ft
Max storage
3,580 ac-ft
Hazard class
High
Owner
GLEN LAKE IRRIGATION DISTRICT

Source: USACE National Inventory of Dams, NID ID MT03756 · Operator website

Nearby Lakes in Lincoln County

Frequently asked questions about Glen Lake

Where is Glen Lake?

Glen Lake is a lake in Lincoln County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.

What is the water quality of Glen Lake?

Glen Lake in Lincoln County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Water clarity: 19.9 ft visibility. Surface area: 300 acres.

Measurements on this page ↑

Is Glen Lake safe to swim in?

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

Swimming on this page ↑

Are there boat ramps on Glen Lake?

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

Access on this page ↑

Can I fish at Glen Lake?

Glen Lake 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.

Access on this page ↑

Where this data comes from

10 measurements from 1 monitoring station, 2020–2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • North American Lake Management SocietyNALMS10 samples · 2020–2023
Monitoring station identifiers (1)

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.

Other records on this page

Named boat-access points from the USGS National Boat Ramps inventory