Siskiwit Lake
Keweenaw County, Michigan4,008 acresView mapDirections
EGLE publishes the water-quality measurements for Siskiwit Lake. Here is what has been measured.
- Oligotrophic
- Impaired · Mercury
- 90 ft max depth
Siskiwit Lake in Keweenaw County, Michigan has water-quality measurements published by EGLE, shown here as reported. Water clarity: 20.5 ft visibility. Phosphorus: 4.4 µg/L. Surface area: 4007.7 acres.
Siskiwit Lake is a 4,008-acre cold, clear oligotrophic lake in Keweenaw County, Michigan with an estimated average depth of about 90 feet. Overall water quality is declining over recent sampling years. The lake supports 2 documented fish species including Lake herring and Lake whitefish. Compared to the 10 other monitored lakes in Keweenaw County, Siskiwit Lake ranks #10 for water quality.
Source: EPA Water Quality Portal sampling records, EGLE, last sampled 2024-07-26. Methodology: how these readings are compared.
Siskiwit Lake covers about 4,000 acres in Keweenaw County. For a place on the water, look through cabin and lake-house rentals near Siskiwit Lake on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Siskiwit Lake is good for
From access and monitoring records, not editorial picks.
- Clear water20.5 ft of visibility
- Camping1 public campground nearby
- Big water4,008 acres
Swimming conditions
Readings onlyLow algae
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. Siskiwit Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury, pCBs. Check local advisories before you swim.
Whether Siskiwit 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 Siskiwit Lake
These are the measurements EGLE publishes for Siskiwit 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 20.5 ft down. Phosphorus 4.4 µg/L. TSI 30.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 20.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 4.4µg/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. | 30 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Siskiwit Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Siskiwit Lake typically sits around 55°F at the surface in August. Summer average is about 52°F. Usually warmest in Aug (about 55°F) and coldest in Jun (about 49°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (49°F) to its warmest (55°F).
Typical surface water temperature by month, from 1,747 field readings (2010–2024) via the EPA Water Quality Portal. See the full Siskiwit Lake water temperature breakdown →
Lake Details
Max depth
~90 ft est.
Surface area
4,008 acres
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Michigan has not published bathymetry for Siskiwit Lake.
Lake Size & Watershed
Watershed (drainage) area
22 sq mi
HydroLAKES / HydroSHEDS
Shoreline
22.9 mi
HydroLAKES / HydroSHEDS
Elevation
650 ft
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.
Recreation & Access
Public campgrounds near Siskiwit Lake
- Malone Bay2.3 km
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 Siskiwit Lake
Compare lakeside cabins, hotels, and vacation rentals near Siskiwit Lake in Keweenaw 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 Siskiwit Lake
Prices for Oct 23–25, 4 adults. Change dates on the map below.
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 Michigan’s top lakes →
Follow Siskiwit Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Siskiwit Lake
Water Quality Trend: Worsening
Based on 9 years of monitoring (2016–2024).
Water clarity
Stable9 years
Phosphorus
Worsening+2.29 µg/L/yr7 years
EPA Impairment Status
Siskiwit Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MI040203000001-02 · Official waterbody report
Nearby Lakes in Keweenaw County
Frequently asked questions about Siskiwit Lake
Where is Siskiwit Lake?
- Siskiwit Lake is a lake in Keweenaw County, Michigan. Its water-quality measurements are published by EGLE and shown on this page as reported.
What is the water quality of Siskiwit Lake?
- Siskiwit Lake in Keweenaw County, Michigan has water-quality measurements published by EGLE, shown here as reported. Water clarity: 20.5 ft visibility. Phosphorus: 4.4 µg/L. Surface area: 4007.7 acres.
Is Siskiwit Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Siskiwit Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury, pCBs. Check local advisories before you swim.
What is the water temperature of Siskiwit Lake?
- Siskiwit Lake typically sits around 55°F at the surface in August, from 1,747 EPA Water Quality Portal field readings (2010–2024). That is a typical value for the month, not a live reading.
How deep is Siskiwit Lake?
- No published bathymetric survey covers Siskiwit Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 90 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 4007.7 acres.
What fish are in Siskiwit Lake?
- Fish species found in Siskiwit Lake include Lake herring, Lake whitefish. Siskiwit Lake is located in Keweenaw County, Michigan.
Are there campgrounds on Siskiwit Lake?
- Siskiwit Lake has 1 public campground from USGS The National Map within 5 km, including Malone Bay. 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 Siskiwit Lake across LakeQuality
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Fish species and best lakes in Keweenaw County
Species activity outlook by water temperature and season
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Where this data comes from
44 measurements from 1 monitoring station, 2016–2024. Retrieved from the EPA Water Quality Portal on 2026-08-26.
Collected and reported by
- National Park Service Water Resources Division
11NPSWRD_WQX44 samples · 2016–2024
Analytical methods
- Secchi Disk
- Alkaline Persulfate Digestion for Total N and P in Water
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
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Public campgrounds from USGS The National Map Structures, within about 3 miles