Lake Onamia
Lake Onamia in Mille Lacs County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 1069 acres.
- Area
- 1,069 acres
- Public access
- Yes
Next lake in Mille Lacs County
Swipe left or right on this bar to open the next or previous lake.
Why Lake Onamia has no grade
We grade a lake only when the monitoring record supports a letter: 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 Lake Onamia, no water-quality sampling on record for this lake.
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.
Lake Onamia is a 1,069-acre lake in Mille Lacs County, Minnesota. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Lake Onamia water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedElevated nutrients
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Lake Onamia
These readings exist but are not enough for an A–F grade — see why.
No clarity data. Trophic State Index: undefined.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) |
Where to stay near Lake Onamia
Compare lakeside cabins, hotels, and vacation rentals near Lake Onamia in Mille Lacs 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 Lake Onamia
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 →
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 1,069 acres |
| Public Access | Yes |
No bathymetric survey has been published for Lake Onamia, so its depth is not documented here.
Recreation & Access
- Onamia LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Lake Onamia
Nearby Lakes in Mille Lacs County
Frequently asked questions about Lake Onamia
Where is Lake Onamia?
- Lake Onamia is a lake in Mille Lacs County, Minnesota. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Lake Onamia?
- Lake Onamia in Mille Lacs County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 1069 acres.
Is Lake Onamia safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lake Onamia is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Are there boat ramps on Lake Onamia?
- Lake Onamia has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Onamia Lake. Public access is listed as yes.
Explore Lake Onamia across LakeQuality
Fish species and top-graded lakes across Minnesota
Species activity outlook by water temperature and season
Top lakes and where to stay in the Mille Lacs Area area
Where to stay at Minnesota's top lakes, each with its grade
Lakes in the Rum River Watershed, ranked by water quality
Minnesota's cleanest and most-polluted lakes, ranked
More Minnesota Lake Rankings
State Parks Near Lake Onamia
Other Lakes in Minnesota
Where this data comes from
Measurements for Lake Onamia come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory