Sy Lake
Manitowoc County, Wisconsin · WBIC 57900
The DNR lists this lake's watershed (Sheboygan River-Frontal Lake Michigan) as suspect or infected with VHS, a fish virus. The listing covers the watershed, not a test of this lake. About VHS
Size
15 acres
Max depth
31 ft
DNR lake type
Simple, Warm, dark water color
Water clarity
2 ft
Low, measured Jul 2000
A warm-water lake type: the DNR groups it with lakes that warm up through summer. This describes the lake type in general, not this lake in particular.
Outline
Drawn from the DNR's 24K hydrography (surveyed 1973), so the shape is approximate and a landing can sit a little off the shore. Open the DNR lake map.
Water clarity
2 ft Secchi depthLowOlder reading
Last measured Jul 21, 2000. 1 reading on record, 2000.
Only one reading is 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 SY LAKE - DEEP HOLE. Checked Oct 23, 2026.
Water temperature
A typical year Modeled estimate
- Ice goes outabout Mar 29 (Mar 24 to Apr 6)
- Surface reaches 48°Fabout Apr 9 (Apr 3 to Apr 19)
- Surface reaches 64°Fabout May 2 (Apr 19 to May 9)
- June surface75°F, usually 74 to 76°F
- July surface81°F, usually 79 to 83°F
- August surface77°F, usually 75 to 79°F
Forms a warm top layer around Apr 15, lasting about 193 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.
More lakes in Manitowoc County
- Wilke Lake1.1 miles away
- Eaton Twin Lakes1.9 miles away
- Eaton Twin Lakes2.1 miles away
- Graf Lake2.2 miles away
- Cedar Lake2.3 miles away
- Prueder Lake2.3 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
- 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
- VHS statusWisconsin DNR VHS status by watershed, checked Oct 24, 2026
- Depth map linkWisconsin DNR lake maps list, checked Oct 24, 2026
See data sources for what each source covers, and about for how the numbers are matched to lakes.