Grindle Lake
Oconto County, Wisconsin40 acresView mapDirections
Wisconsin DNR publishes the water-quality measurements for Grindle Lake. Here is what has been measured.
- Mesotrophic
- 23 ft max depth
- Public access
Grindle Lake in Oconto County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 9 ft visibility. Phosphorus: 12.2 µg/L. Maximum depth: 23 ft. Surface area: 40 acres.
Wisconsin DNR lists Panfish as common on Grindle Lake. DNR survey details →
Grindle Lake is a 40-acre mesotrophic lake in Oconto County, Wisconsin with a maximum depth of 23 feet. Water clarity is declining over recent sampling years. The lake supports 3 documented fish species including Panfish, Largemouth Bass, and Northern Pike. Public access is available with 2 public boat landings. Compared to the 38 other monitored lakes in Oconto County, Grindle Lake ranks #14 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-06-22. Methodology: how these readings are compared.
Grindle Lake covers about 40 acres in Oconto County. It has 2 public boat landings, so a lakefront rental is not the only way to get a boat on the water. For a place on the water, look through cabin and lake-house rentals near Grindle Lake on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Grindle Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch2 documented ramps
- Fishing3 species recorded
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. Check local advisories before you swim.
Whether Grindle 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.
Water quality measurements for Grindle Lake
These are the measurements Wisconsin DNR publishes for Grindle Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 9 ft. Phosphorus 12.2 µg/L. TSI 43.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 9ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 12.2µg/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. | 43 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Grindle Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Grindle Lake typically sits around 72°F at the surface in September. Summer average is about 75°F. Usually warmest in Jul (about 79°F) and coldest in May (about 64°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (64°F) to its warmest (79°F).
Typical surface water temperature by month, from 16 field readings (2024–2025) via the EPA Water Quality Portal. See the full Grindle Lake water temperature breakdown →
Wisconsin DNR lists Panfish as common on Grindle Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Grindle Lake’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is stable. 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 2002. 1 station on file (most recent sample 2025).
Fish Species (DNR-rated)
Lake Details
Max depth
23 ft
Surface area
40 acres
Public access
Yes
Listed by Wisconsin DNR
Lake Size & Watershed
Watershed (drainage) area
0 sq mi
HydroLAKES / HydroSHEDS
Shoreline
1 mi
HydroLAKES / HydroSHEDS
Elevation
942 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Grindle LakePublic
- Waupee FlowagePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Grindle Lake
Compare lakeside cabins, hotels, and vacation rentals near Grindle Lake in Oconto 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 Grindle Lake
Prices for Oct 16–18, 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 Grindle Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Grindle 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.
Water Quality Trend: Stable
Based on 7 years of monitoring (2020–2026).
Water clarity
Worsening6 years
Phosphorus
Improving-0.24 µg/L/yr7 years
Reservoir Info (USACE NID)
Grindle Lake is a man-made reservoir impounded by the Waupee Dam (completed 1944), built primarily for fish and wildlife pond on the WAUPEE CREEK; earth-type dam, 13 ft tall and 285 ft long.
- Surface area
- 95 ac
- Normal storage
- 152 ac-ft
- Max storage
- 562 ac-ft
- Drainage area
- 11 sq mi
- Hazard class
- Significant
- Owner
- USDA FS
Source: USACE National Inventory of Dams, NID ID WI00673 · Operator website · Matched by proximity (0.59 km)
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Grindle Lake under Clean Water Act (NPDES) discharge permits.
- Premium Waters IncRiverview · 0.4 mi away · NPDES WI0047147
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Nearby Lakes in Oconto County
Frequently asked questions about Grindle Lake
Where is Grindle Lake?
- Grindle Lake is a lake in Oconto County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Grindle Lake?
- Grindle Lake in Oconto County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 9 ft visibility. Phosphorus: 12.2 µg/L. Maximum depth: 23 ft. Surface area: 40 acres.
Is Grindle Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Grindle Lake?
- Grindle Lake typically sits around 72°F at the surface in September, from 16 EPA Water Quality Portal field readings (2024–2025). That is a typical value for the month, not a live reading.
How deep is Grindle Lake?
- Grindle Lake has a maximum depth of 23 feet. The lake covers 40 acres.
What fish are in Grindle Lake?
- Fish species found in Grindle Lake include Panfish, Largemouth Bass, Northern Pike. Grindle Lake is located in Oconto County, Wisconsin.
What did the DNR fisheries survey find at Grindle Lake?
- Wisconsin DNR lists Panfish as common on Grindle Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Grindle Lake’s water-quality measurements separately, and the water-quality trend over 7 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Grindle Lake?
- Grindle Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Grindle Lake, Waupee Flowage. Public access is listed as yes.
Can I fish at Grindle Lake?
- Grindle Lake has 2 documented boat landings 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 Grindle Lake across LakeQuality
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Fish species and best lakes in Oconto County
Species activity outlook by water temperature and season
Where to stay at Wisconsin's top lakes, each with its readings
Wisconsin's cleanest lakes, ranked on agency measurements
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State Parks Near Grindle Lake
Other Lakes in Wisconsin
Mesotrophic Lakes in Wisconsin
Where this data comes from
62 measurements from 1 monitoring station, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX62 samples · 2020–2026
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
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