Lake Montanis
Lake Montanis in Barron County, Wisconsin has a water quality grade of D (Nutrient-rich). Water clarity: 2 ft visibility. Phosphorus: 48.5 µg/L. Maximum depth: 14 ft. Surface area: 212 acres.
- Clarity
- 2 ft
- Typical in August
- 74°F
- Max depth
- 14 ft
- Area
- 212 acres
- Type
- Eutrophic
- Trend
- → Stable
- Public access
- Yes
Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Lake Montanis →
Next lake in Barron County
Lake Montanis is a 212-acre productive, nutrient-rich eutrophic lake in Barron County, Wisconsin with a maximum depth of 14 feet. Water quality is graded D based on 1 sampling years through 2026. The lake supports 4 documented fish species including Panfish, Largemouth Bass, and Northern Pike. Public access is available with 3 public boat landings. Compared to the 27 other monitored lakes in Barron County, Lake Montanis ranks #22 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-06-22. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyElevated nutrients
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum
Water Quality Grade: D (Nutrient-rich)
Very murky, less than 2 ft of visibility. Phosphorus level: 48.5 µg/L. Trophic State Index: 64.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2 ft | Not graded |
| Phosphorus | 48.5 µg/L | Poor |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 64 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Lake Montanis
Compare lakeside cabins, hotels, and vacation rentals near Lake Montanis in Barron County, Wisconsin — 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 grade measures nutrients and algae, not lodging — cabins and rentals around Lake Montanis are listed below.
Top-rated places to stay near Lake Montanis
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 whole trip? See where to stay at Wisconsin’s top lakes →
Water Temperature
Lake Montanis typically sits around 74°F at the surface in August. Summer average is about 75°F. Usually warmest in Jun (about 76°F) and coldest in Aug (about 74°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 14 field readings (2024–2026) via the EPA Water Quality Portal. See the full Lake Montanis water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 14 ft |
| Surface Area | 212 acres |
| Public Access | Yes |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Veterans Memorial ParkPublic
- 18 1/2 AvenuePublic
- 22 22 1/4 StreetPublic
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Lake Montanis
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 2001. 1 station on file (most recent sample 2025).
Fish Species (DNR-rated)
DNR Reports & Resources
Wisconsin DNR Fisheries scientists publish multi-year survey reports for Lake Montanis covering fish populations, stocking, water quality, and management. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- 2024Lake Montanis fishery survey, 2024Fisheries Survey · WI DNR · 2024 (PDF)
Water Quality Trend: → Stable
Based on 7 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | +0.02 m/yr | 7 |
| Phosphorus | → Stable | -0.5 µg/L/yr | 7 |
EPA Impairment Status
Lake Montanis is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5R).
Causes of impairment
Source: EPA ATTAINS assessment unit WI10004574 · Official waterbody report
County Ranking
Ranked #22 of 28 lakes in Barron County
Nearby Lakes With Higher Grades
Lake Montanis holds Grade D. 3 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in Barron County
Frequently asked questions about Lake Montanis
What is the water quality grade for Lake Montanis?
- Lake Montanis in Barron County, Wisconsin has a water quality grade of D (Nutrient-rich). Water clarity: 2 ft visibility. Phosphorus: 48.5 µg/L. Maximum depth: 14 ft. Surface area: 212 acres.
Is Lake Montanis safe to swim in?
- Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum. Lake Montanis has a water quality grade of D (Nutrient-rich). Always check local health department advisories before swimming.
What is the water temperature of Lake Montanis?
- Lake Montanis typically sits around 74°F at the surface in August, from 14 EPA Water Quality Portal field readings (2024–2026). That is a typical value for the month, not a live reading.
How deep is Lake Montanis?
- Lake Montanis has a maximum depth of 14 feet. The lake covers 212 acres.
What fish are in Lake Montanis?
- Fish species found in Lake Montanis include Panfish, Largemouth Bass, Northern Pike, Walleye. Lake Montanis is located in Barron County, Wisconsin.
Are there boat ramps on Lake Montanis?
- Lake Montanis has 3 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Veterans Memorial Park, 18 1/2 Avenue, 22 22 1/4 Street. Public access is listed as yes.
Explore Lake Montanis across LakeGrade
Depth, room, public access, and the state wake-sport rules
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Fish species and best lakes in Barron County
Species activity outlook by water temperature and season
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High nutrients, frequent algae, reduced clarity
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Where this data comes from
36 measurements from 1 monitoring station, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX36 samples · 2020–2026
Analytical methods
- Phosphorus by Colorimetry
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Fish and recreation data from Wisconsin DNR Lakes
Named boat-access points from the USGS National Boat Ramps inventory