Where is Seven Island Lake?

Seven Island Lake is a lake in Lincoln County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.

How deep is Seven Island Lake?

Seven Island Lake has a maximum depth of 31 feet. The lake covers 132 acres.

What fish are in Seven Island Lake?

Fish species found in Seven Island Lake include Musky, Panfish, Largemouth Bass, Northern Pike, Walleye. Seven Island Lake is located in Lincoln County, Wisconsin.

Are there boat ramps on Seven Island Lake?

Seven Island Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Seven Island Lake. Public access is listed as yes.

Can I fish at Seven Island Lake?

Seven Island 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 Wisconsin's fish and wildlife agency, so check its current regulations before you go.

Seven Island Lake

Lincoln County, Wisconsin132 acresView map Directions

Wisconsin DNR publishes the water-quality measurements for Seven Island Lake. Here is what has been measured.

Clarity

14 ft

Clearer than most

Secchi · sampled 2025

Phosphorus

9.9 µg/L

Less phosphorus than most

Measured by Wisconsin DNR

Max depth

31 ft

Bathymetric survey

Area

132 acres

Surface area

Type

Oligotrophic

Trophic class

Trend

Improving

7 years of samples

Oligotrophic
31 ft max depth
Public access
Limited data

See the measurements Directions Where to stay

Seven Island Lake in Lincoln County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 14 ft visibility. Phosphorus: 9.9 µg/L. Maximum depth: 31 ft. Surface area: 132 acres.

Wisconsin DNR lists Largemouth Bass as common on Seven Island Lake. DNR survey details →

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Seven Island Lake is a 132-acre cold, clear oligotrophic lake in Lincoln County, Wisconsin with a maximum depth of 31 feet. Overall water quality is improving over recent sampling years. The lake supports 5 documented fish species including Musky, Panfish, and Largemouth Bass. Public access is available with 1 public boat landing. Compared to the 12 other monitored lakes in Lincoln County, Seven Island Lake ranks #5 for water quality.

Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2025-08-31. Methodology: how these readings are compared.

Seven Island Lake covers about 130 acres in Lincoln County. It has one public boat landing. If you are planning to stay, you can search lake houses and cabins around Seven Island Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.

What Seven Island Lake is good for

From access and monitoring records, not editorial picks.

Clear water14 ft of visibility
Boat launch1 documented ramp
Fishing5 species recorded
Deep water31 ft surveyed max depth

Swimming conditions

Readings only

Limited 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 Seven Island Lake is safe to swim in today is a call for the Wisconsin Department of Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

Compare swimming lakes near Rhinelander →

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Water quality measurements for Seven Island Lake

These are the measurements Wisconsin DNR publishes for Seven Island Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

Good clarity, visible to about 14 ft. Phosphorus 9.9 µg/L. TSI 38.

Water quality readings
Measure	Reading	Where it sits
Water clarity (Secchi depth)	14ft	Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer.
Total phosphorus	9.9µg/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.	38	Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic

Low nutrients, clear water. No reading is a swimming clearance.

Ask about Seven Island Lake

Answers come straight from the public measurements and survey records on this page.

DNR fisheries survey

Wisconsin DNR lists Largemouth Bass as common on Seven Island Lake.

A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Seven Island Lake’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.

WI DNR Lake Profile

Authoritative data from the Wisconsin DNR LakePages. Monitored by volunteers since 1993. 1 station on file (most recent sample 2025).

DNR Assessment

Excellent · Deep Seepage lake

Trophic State Index 39 (oligotrophic) · 5-year average

Fish Species (DNR-rated)

Largemouth Bass(Common)Walleye(Common)Musky(Present)Panfish(Present)Northern Pike(Present)

Contour map (PDF) →Full WI DNR LakePage →Water quality stations →

DNR Reports & Resources

Wisconsin DNR Fisheries scientists publish multi-year survey reports for Seven Island Lake 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).

2024
Seven Island Lake spring summary report, 2024
Fisheries Survey · WI DNR · 2024 (PDF)

Lake Details

Max depth

31 ft

Surface area

132 acres

Public access

Yes

Listed by Wisconsin DNR

Lake Size & Watershed

Watershed (drainage) area

1 sq mi

HydroLAKES / HydroSHEDS

Shoreline

2.6 mi

HydroLAKES / HydroSHEDS

Elevation

1,729 ft

Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).

Recreation & Access

Boat Landings

Yes

Public Access

Seven Island LakePublic

Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps

Stays via Stay22

Stays near Seven Island Lake

Compare lakeside cabins, hotels, and vacation rentals near Seven Island Lake in Lincoln 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.

Top-rated places to stay near Seven Island Lake

Prices for Oct 9–11, 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 Wisconsin’s top lakes →

Follow Seven Island Lake’s readings

Email me when new measurements post for this lake. Updates stay free.

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Fish Species

Musky Panfish Largemouth Bass Northern Pike Walleye

Click a species to see every lake where it is documented.

Fishing Seven Island Lake

Invasive & Introduced Species

Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.

Chinese Mystery SnailEurasian Water-Milfoil

Water Quality Trend: Improving

Based on 7 years of monitoring (2020–2026).

Water clarity
Improving
6 years
Phosphorus
Improving
-0.67 µg/L/yr7 years

See year-by-year chart →

Nearby Lakes in Lincoln County

Fish Lake—View →Long Lake14.5 ft clear · Oligotrophic—View →Lake Buteau19.4 ft clear · Oligotrophic—View →Clara Lake23.8 ft clear—View →Mary Lake21 ft clear—View →Bass Lake12.5 ft clear · Mesotrophic—View →

Frequently asked questions about Seven Island Lake

Where is Seven Island Lake?: Seven Island Lake is a lake in Lincoln County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Seven Island Lake?: Seven Island Lake in Lincoln County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 14 ft visibility. Phosphorus: 9.9 µg/L. Maximum depth: 31 ft. Surface area: 132 acres.
Is Seven Island Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Seven Island Lake?: Seven Island Lake has a maximum depth of 31 feet. The lake covers 132 acres.
What fish are in Seven Island Lake?: Fish species found in Seven Island Lake include Musky, Panfish, Largemouth Bass, Northern Pike, Walleye. Seven Island Lake is located in Lincoln County, Wisconsin.
What did the DNR fisheries survey find at Seven Island Lake?: Wisconsin DNR lists Largemouth Bass as common on Seven Island Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Seven Island Lake’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Seven Island Lake?: Seven Island Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Seven Island Lake. Public access is listed as yes.
Can I fish at Seven Island Lake?: Seven Island 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 Wisconsin's fish and wildlife agency, so check its current regulations before you go.

Explore Seven Island Lake across LakeQuality

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Every Wisconsin lake with its Wisconsin DNR measurements

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Official ratings and named-lake measurements

State Parks Near Seven Island Lake

Council Grounds State Park

State Park · 21.5 mi

Other Lakes in Wisconsin

Crescent Lake

Oneida County · 14 ft

Lake Julia

Oneida County · 9.9 ft

Squash Lake

Oneida County · 17.5 ft

Nose Lake

Oneida County · 12 ft

Washburn Lake

Oneida County · 7.5 ft

Horseshoe Lake

Langlade County · 8 ft

Oligotrophic Lakes in Wisconsin

Squash Lake Nose Lake Deep Hole Lake Manson Lake

Where this data comes from

51 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

Wisconsin Department of Natural ResourcesWIDNR_WQX51 samples · 2020–2025

Analytical methods

Phosphorus by Colorimetry

Monitoring station identifiers (1)

WIDNR_WQX-353168

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

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