Ottawa Lake
Iron County, Michigan531 acresView mapDirections
EGLE publishes the water-quality measurements for Ottawa Lake. Here is what has been measured.
- Oligotrophic
- Public access
- Limited data
Ottawa Lake in Iron County, Michigan has water-quality measurements published by EGLE, shown here as reported. Water clarity: 19.3 ft visibility. Phosphorus: 10 µg/L. Surface area: 531.4 acres.
Ottawa Lake is a 531-acre cold, clear oligotrophic lake in Iron County, Michigan. Water clarity is improving over recent sampling years. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 20 other monitored lakes in Iron County, Ottawa Lake ranks #14 for water quality.
Source: EPA Water Quality Portal sampling records, EGLE, last sampled 2023-08-27. Methodology: how these readings are compared.
What Ottawa Lake is good for
From access and monitoring records, not editorial picks.
- Clear water19.3 ft of visibility
- Boat launch1 documented ramp
- Camping2 public campgrounds nearby
Swimming conditions
Readings onlyLimited data
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Ottawa Lake is safe to swim in today is a call for the Michigan Department of Environment, Great Lakes, and Energy (EGLE) and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Ottawa Lake
These are the measurements EGLE publishes for Ottawa 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 19.3 ft down. Phosphorus 10 µg/L. TSI 36.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 19.3ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 10µg/L | Good GoodFairPoor |
| 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. | 36 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Ottawa Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
531 acres
Public access
Yes
Listed by EGLE
No bathymetric survey has been published for Ottawa Lake, so its depth is not documented here.
Recreation & Access
- Lake OttawaPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Public campgrounds near Ottawa Lake
- Lake Ottawa Camp0.4 km
- Lake Ottawa Pavilion0.7 kmReserve
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 Ottawa Lake
Compare lakeside cabins, hotels, and vacation rentals near Ottawa Lake in Iron County, Michigan — 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 Ottawa Lake
Prices for Oct 23–25, 4 adults. Change dates on the map below.
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Fishing Ottawa Lake
Water Quality Trend: Stable
Based on 6 years of monitoring (2017–2023).
Water clarity
Improving6 years
Phosphorus
Worsening+0.57 µg/L/yr6 years
Nearby Lakes in Iron County
Frequently asked questions about Ottawa Lake
Where is Ottawa Lake?
- Ottawa Lake is a lake in Iron County, Michigan. Its water-quality measurements are published by EGLE and shown on this page as reported.
What is the water quality of Ottawa Lake?
- Ottawa Lake in Iron County, Michigan has water-quality measurements published by EGLE, shown here as reported. Water clarity: 19.3 ft visibility. Phosphorus: 10 µg/L. Surface area: 531.4 acres.
Is Ottawa Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Are there boat ramps on Ottawa Lake?
- Ottawa Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lake Ottawa. Public access is listed as yes.
Can I fish at Ottawa Lake?
- Ottawa 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 Michigan's fish and wildlife agency, so check its current regulations before you go.
Are there campgrounds on Ottawa Lake?
- Ottawa Lake has 2 public campgrounds from USGS The National Map within 5 km, including Lake Ottawa Camp, Lake Ottawa Pavilion. 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.
Explore Ottawa Lake across LakeQuality
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Fish species and best lakes in Iron County
Species activity outlook by water temperature and season
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Where to stay at Michigan's top lakes, each with its readings
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Where this data comes from
45 measurements from 1 monitoring station, 2017–2023. Retrieved from the EPA Water Quality Portal on 2026-08-26.
Collected and reported by
- Michigan EGLE - MiCorps
21MICH_MICORPS45 samples · 2017–2023
Analytical methods
- Phosphorus by Colorimetry
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
Public campgrounds from USGS The National Map Structures, within about 3 miles