Skip to content

Michigan lake depth maps

Allen Lake depth map

Allen Lake in Lenawee County, Michigan reaches a depth of 75 feet. Allen Lake is charted here across 5 closed depth contours, from the 10 ft line down to 40 ft, enclosing about 39 acres of water. Half of that water lies inside the 30 ft line, and only 6.4 acres lie inside the deepest one. Every contour is on the interactive map below, free and without an account.

Data: Michigan DNR Inland Lake Contours (public record). Contours closed, checked and area-computed by Jordan Carter, founder of GilledIt · page updated

Allen Lake depth chart: 5 depth contours from 10 to 40 ft

Data: Michigan DNR Inland Lake Contours (public record), retrieved August 2026 · depths change over time · not for navigation

Allen Lake depth chart data: water enclosed by each contour
Depth contourWater inside itShare of mapped water
10 ft39 acres100%
15 ft33 acres86%
20 ft28 acres74%
30 ft17 acres45%
40 ft6.4 acres17%

Acreages are computed from the closed Michigan DNR Inland Lake Contours contour rings, with islands subtracted. Shares are of the 39 acres inside the outermost charted contour (the 10 ft line), which is the outer edge of the mapped water, several state files carry no 0 ft shoreline line, so this is not the same as a share of the lake's published surface area. The survey also records a 75 ft sounding, marked as a point rather than a closed contour, so it is not charted as a band.

Fishing Allen Lake: steep walls and a big basin

The survey encloses about 39 acres of Allen Lake inside its 10 ft contour, and half of that water lies inside the 30 ft line, so depth comes quickly here, with no long shallow margin before the bottom drops away. Between 10 and 15 ft the mapped water sheds 6 acres in 5 ft of depth, the sharpest change on the chart, start on that band, because it is where the bottom stops being flat. The deepest 40 ft contour holds 6.4 acres, 17% of the mapped water, toward the middle of the lake. 75 ft of water makes this a two-story fishery: warm-water fish hold the 10-to-30 ft ground while the basin can stay cold below the summer thermocline, and the traffic between the two runs along the 10–15 ft break at first and last light.

Ice fishing on Allen Lake

Allen Lake freezes later and less evenly than the shallow waters around it, and the winter bite sets up on the first real break rather than out over the 40 ft hole. The 10–15 ft band on the chart above is that edge: 6 acres of bottom tilt away there, and panfish and walleye slide up and down it through the day. Late ice pushes fish back onto the 10-to-30 ft flat. Check ice thickness locally before you walk out.

Allen Lake depth map FAQs

How deep is Allen Lake?
Allen Lake reaches a maximum depth of 75 feet in the Michigan DNR Inland Lake Contours survey. Most of it is far shallower: the survey charts 5 closed depth contours over about 39 acres, and half of that water sits inside the 30 ft line. The 75 ft figure is a single recorded sounding rather than a closed contour, so the deepest line you can actually trace on the map is 40 ft.
Where is the deepest part of Allen Lake?
The deepest charted water on Allen Lake lies inside the 40 ft contour, toward the middle of the lake. That contour encloses 6.4 acres, 17% of the mapped water, so it is a broad slice of the bottom rather than a pinpoint target, the depth chart above gives the contour to line up on.
How much of Allen Lake is shallower than 30 feet?
About half. The 30 ft contour encloses 17 acres of the roughly 39 acres inside the outer 10 ft line, so the other half of the water is shallower than 30 feet. The sharpest drop is between 10 and 15 feet, where the mapped water sheds 6 acres.
How accurate is this Allen Lake depth map?
The contours come from the Michigan DNR Inland Lake Contours survey, retrieved August 2026 and last rebuilt on August 19, 2026. Depths change over time with water levels and sediment, so treat this map as a planning guide for fishing, and never use it for navigation. Acreages are computed from the published contour geometry, not from a separate area survey, so read them as close approximations.

Depth maps for lakes near Allen Lake

Mapped fishing venues near Allen Lake

Allen Lake in the venue directory covers access and fishing details for this water.

Fishing in Michigan needs a state license: Michigan fishing license guide · all Michigan venues