Lost Lake
Lost Lake in Hubbard County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 8 ft visibility.
- Clarity
- 8 ft
- Typical in August
- 69°F
- Mean depth
- ~13 ft est.
Next lake in Hubbard County
Why Lost Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Lost Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Lost Lake is a lake in Hubbard County, Minnesota with an estimated average depth of about 13 feet.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2022-09-13. Grade methodology: LakeGrade methodology.
Watch Lost Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Lost Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Moderate clarity, visible to about 8 ft. Trophic State Index: 47.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 8 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 47 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Lost Lake
Compare lakeside cabins, hotels, and vacation rentals near Lost Lake in Hubbard County, Minnesota — 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 Lost Lake
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 Minnesota’s top lakes →
Water Temperature
Lost Lake typically sits around 69°F at the surface in August. Summer average is about 69°F. Usually warmest in Jul (about 70°F) and coldest in May (about 59°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 20 field readings (2022–2022) via the EPA Water Quality Portal. See the full Lost Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Average Depth | ~13 ft est. |
Depth marked “est.” is a modeled estimate from HydroLAKES, not a measured survey. Minnesota has not published bathymetry for Lost Lake.
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Fishing Lost Lake
Graded lakes near Lost Lake
Lost Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Hubbard County
Frequently asked questions about Lost Lake
What is the water quality grade for Lost Lake?
- Lost Lake in Hubbard County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 8 ft visibility.
Is Lost Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lost Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
What is the water temperature of Lost Lake?
- Lost Lake typically sits around 69°F at the surface in August, from 20 EPA Water Quality Portal field readings (2022–2022). That is a typical value for the month, not a live reading.
How deep is Lost Lake?
- No published bathymetric survey covers Lost Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 13 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Explore Lost Lake across LakeGrade
Fish species and top-graded lakes across Minnesota
Fish species and best lakes in Hubbard County
Species activity outlook by water temperature and season
Top lakes and where to stay in the Park Rapids Area area
Where to stay at Minnesota's top lakes, each with its grade
Lakes in the Mississippi Headwaters, ranked by water quality
Minnesota's cleanest and most-polluted lakes, ranked
More Minnesota Lake Rankings
State Parks Near Lost Lake
Other Lakes in Minnesota
Mesotrophic Lakes in Minnesota
Where this data comes from
20 measurements from 1 monitoring station, 2022. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA20 samples · 2022
Analytical methods
- Field measurement/observation, generic method
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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder