The contours
Each band is another 10 feet down, and water inside a band is at least that deep. The two light patches are shoals where the bottom rises back up. Hover or tap a band for its depth; the dot marks the 79-foot hole.
How to read it
What the contours show about Winona.
- 1The main basin holds the deep water. Depth steps down band by band to the 79-foot hole in the middle. The northwest arm by the canals is much shallower: most of it is under 10 feet, with one small pocket past 20.
- 2The east side drops off fast. Along parts of the east shore the 20-foot line comes within about 110 feet of the bank, which is inside the idle-speed zone. See the 200-foot lap for where depth and the speed rule overlap.
- 3Watch the mid-lake shoal. South of the deep basin the bottom rises from over 20 feet of water to less than 10, then drops away again. It shows as the light two-ring patch on the map, with a second small shoal to its east. Both sit well away from shore, in water that otherwise runs 15 to 25 feet deep.
- 4Bands show the minimum depth. A band means the water was at least that deep in August 2017. Lake level moves, so keep your sounder on in anything shallower than you draw.
- 5Fish hold on the drop-offs. The 10-to-30-foot contour steps on the south and east sides, and the edges of the shoals, give walleye, bass, and perch their structure. The Lilly Center profile covers the fishery.
How this map was made
Where the lines come from, and how far to trust them.
The depth figures come from the Indiana DNR. In August 2017 the DNR ran a bathymetric survey of Winona Lake and published it as a map with contours every 10 feet. That file carries its contours as vector line work, so every ring here was read directly out of the survey rather than traced by eye. Each ring takes its depth from the survey's printed labels and from how the rings nest.
Three rings on the survey carry no label because they enclose shoals rather than deeper water: inside them the bottom rises back through the contour. The survey's color fill (lighter is shallower) confirms all three, and they are drawn here in the lighter color of their shallow side.
The survey is also a GeoPDF: the file pins its map frame to real coordinates in NAD83 UTM Zone 16N, so the contours land on this map through the survey's own georeferencing with no hand fitting. As a check, the survey's shoreline runs within about 16 feet of the OpenStreetMap shoreline, small next to the 10-foot contour interval.
As a second check, the water inside the 20-foot contour on this page (net of the shoal) works out to 316 acres. The boating map read the same contour from the same survey by an independent path and got 319, a difference of about 1%.
| Source survey | Indiana DNR, August 2017, published with permission to reprint with credit |
| Contour interval | 10 ft, from 10 to 70, plus the labeled 79 ft maximum |
| Rings extracted | 13: the nested main-basin stack, the northwest-arm rings, a 30-foot pocket, and three shoal rings |
| Georeferencing | Embedded in the survey (GeoPDF, NAD83 UTM Zone 16N); shoreline agrees with OpenStreetMap within about 16 ft |
| Water 20 ft or deeper | 319 acres, 56% of the lake |
| Average depth | 30 ft, per the Lilly Center for Lakes & Streams |
Use it on the water
Conditions, rules, and the source material.
The 200-Foot Lap
The idle-speed line as a 5.2-mile loop, and where deep water and the speed rule overlap.
Open the boating mapLake Today
Wind, gusts, water conditions, sunrise and sunset, and the watersports outlook before you launch.
Check conditionsThe Original Survey
The DNR's 2017 sheet this page is built from, with the aerial photo underlay and label placement.
Open the surveyWinona Lake Facts & Research
Size, depth, fishing, water quality, and the Lilly Center's full archive of lake studies.
View lake profile