Grandfather Flowage
Lincoln County, Wisconsin · WBIC 1502400
This lake has fishing rules that differ from the standard ones for its area. Check the official rules before you fish. Official regulations
Size
223 acres
Max depth
32 ft
DNR lake type
Complex, Riverine
Water clarity
3.5 ft
Low, measured Aug 2003
A river-like water type, with flow instead of a still basin. This describes the lake type in general, not this lake in particular.
Outline
Numbered dots are boat landings; tap one for directions. The list below has the same numbers. Drawn from the DNR's 24K hydrography (surveyed 1981), so the shape is approximate and a landing can sit a little off the shore. Open the DNR lake map.
Water clarity
3.5 ft Secchi depthLowOlder reading
Last measured Aug 20, 2003. 2 readings on record, 2003.
Only a few readings are on record.
Nothing has been measured in the last 5 years, so this may not match the lake today.
Secchi depth is how far down a white disk stays visible. A bigger number means clearer water. Clear means a Secchi depth of 10 feet or more, moderate 5 to 10 feet, low under 5 feet.
Wisconsin DNR water monitoring (volunteer and staff), via the Water Quality Portal; station GRANDFATHER FLOWAGE - DEEP HOLE. Checked Oct 23, 2026.
Water temperature
A typical year Modeled estimate
- Ice goes outabout Apr 18 (Apr 10 to Apr 25)
- Surface reaches 48°Fabout Apr 27 (Apr 18 to May 4)
- Surface reaches 64°Fabout May 14 (May 8 to May 22)
- June surface73°F, usually 71 to 74°F
- July surface78°F, usually 77 to 80°F
- August surface74°F, usually 72 to 76°F
Forms a warm top layer around May 2, lasting about 164 days.
A computer model of this lake's typical weather and water, built from 15 years, 2005 to 2019. Ranges show the middle half of years. The model was not calibrated against measured temperatures for this lake. It is an estimate, not a measurement.
Modeled: U.S. Geological Survey lake temperature data release (doi:10.5066/P9CA6XP8).
Today at the lake
Forecast: National Weather Service (no endorsement implied). Sunrise, sunset and moon phase are calculated. The moon phase can be a day off.
Fish recorded near this lake
- Black Bullhead Ameiurus melas2003; 2 records
- Black Crappie Pomoxis nigromaculatus2003; 3 records
- Bluegill Lepomis macrochirus2003; 3 records
- Burbot Lota lota2003; 1 record
- Golden Redhorse Moxostoma erythrurum2003; 2 records
- Golden Shiner Notemigonus crysoleucas2003; 2 records
- Johnny Darter Etheostoma nigrum2003; 1 record
- Largemouth Bass Micropterus salmoides2003; 1 record
- Logperch Percina caprodes2003; 1 record
- Mottled Sculpin Cottus bairdii2003; 1 record
- Northern Pike Esox lucius2003; 2 records
- Pumpkinseed Lepomis gibbosus2003; 3 records
- Shorthead Redhorse Moxostoma macrolepidotum2003; 1 record
- Smallmouth Bass Micropterus dolomieu2003; 3 records
- Trout-Perch Percopsis omiscomaycus2003; 1 record
- Walleye Sander vitreus2003; 3 records
- White Sucker Catostomus commersonii2003; 1 record
- Yellow Bullhead Ameiurus natalis2003; 1 record
- Yellow Perch Perca flavescens2003; 3 records
Recorded in open fish survey and museum records (GBIF). A record shows a fish was found near this lake in that year, not that it is there now, and says nothing about how many. Most coordinates are rounded to about 1 km, so a record is attached only when one lake is the clear match.
Open fish survey and museum records from GBIF; datasets are listed on the sources page. Checked Oct 23, 2026.
Boat landings
- 1Grandfather Flowage AccessCarry-in access · Unimproved surface · Other
Directions
Wisconsin DNR public boat access sites. Checked Oct 23, 2026.
More lakes in Lincoln County
- Olivotti Lake3.1 miles away
- Tug Lake3.9 miles away
- Grandmother Flowage4.5 miles away
- Larson Lake5.8 miles away
- Black Alder Lake6.4 miles away
- Knight Lake6.9 miles away
Where this comes from
- Size, depth and lake typeWisconsin DNR lake classifications, checked Oct 23, 2026
- OutlineWisconsin DNR 24K hydrography, checked Oct 23, 2026
- Regulations linkWisconsin DNR fishing regulations (linked, not restated), checked Oct 23, 2026
- Boat landingsWisconsin DNR public boat access sites, checked Oct 23, 2026
- Water clarityWisconsin DNR water monitoring, via the Water Quality Portal, checked Oct 23, 2026
- Typical-year temperatureU.S. Geological Survey lake temperature model (modeled estimate), checked Oct 23, 2026
- Fish recordedOpen fish survey and museum records, via GBIF, checked Oct 23, 2026
- VHS statusWisconsin DNR VHS status by watershed, checked Oct 24, 2026
See data sources for what each source covers, and about for how the numbers are matched to lakes.
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