How deep is Derby Lake?

Derby Lake reaches a maximum depth of 87 feet in the Michigan DNR Inland Lake Contours survey. Most of it is far shallower: the survey charts 10 closed depth contours over about 111 acres, and half of that water sits inside the 40 ft line. The 87 ft figure is a single recorded sounding rather than a closed contour, so the deepest line you can actually trace on the map is 80 ft.

Where is the deepest part of Derby Lake?

The deepest charted water on Derby Lake lies inside the 80 ft contour, toward the western side of the lake. That contour encloses 6.6 acres, 5.9% of the mapped water, so it is a small target on a small water, the depth chart above gives the contour to line up on.

How much of Derby Lake is shallower than 40 feet?

About half. The 40 ft contour encloses 50 acres of the roughly 111 acres inside the outer 5 ft line, so the other half of the water is shallower than 40 feet. The sharpest drop is between 5 and 10 feet, where the mapped water sheds 31 acres.

How accurate is this Derby 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.

Michigan lake depth maps

Derby Lake depth map

Derby Lake in Montcalm County, Michigan reaches a depth of 87 feet. Derby Lake is charted here across 10 closed depth contours, from the 5 ft line down to 80 ft, enclosing about 111 acres of water. Half of that water lies inside the 40 ft line, and only 6.6 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 August 19, 2026

Derby Lake depth chart: 10 depth contours from 5 to 80 ft

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

Derby Lake depth chart data: water enclosed by each contour
Depth contour	Water inside it	Share of mapped water
5 ft	111 acres	100%
10 ft	80 acres	72%
15 ft	70 acres	63%
20 ft	64 acres	58%
30 ft	58 acres	52%
40 ft	50 acres	45%
50 ft	40 acres	36%
60 ft	32 acres	29%
70 ft	26 acres	23%
80 ft	6.6 acres	5.9%

Acreages are computed from the closed Michigan DNR Inland Lake Contours contour rings, with islands subtracted. Shares are of the 111 acres inside the outermost charted contour (the 5 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 87 ft sounding, marked as a point rather than a closed contour, so it is not charted as a band.

Fishing Derby Lake: a stepped drop into deep water

About 111 acres of Derby Lake sit inside the survey's 5 ft contour, and half of that water is already gone by the 40 ft line: the drop to the deep basin comes in stages, each contour giving up another slice of water, rather than in one abrupt wall. The steepest break on the chart runs from 5 down to 10 ft: 31 acres of bottom fall away across 5 ft there, which makes that band the first contour to work. The deepest 80 ft contour holds 6.6 acres, 5.9% of the mapped water, toward the western side of the lake. 87 ft of water makes this a two-story fishery: warm-water fish hold the 5-to-40 ft ground while the basin can stay cold below the summer thermocline, and the traffic between the two runs along the 5–10 ft break at first and last light.

Ice fishing on Derby Lake

Derby 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 80 ft hole. The 5–10 ft band on the chart above is that edge: 31 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 5-to-40 ft flat. Check ice thickness locally before you walk out.

Derby Lake depth map FAQs

How deep is Derby Lake?: Derby Lake reaches a maximum depth of 87 feet in the Michigan DNR Inland Lake Contours survey. Most of it is far shallower: the survey charts 10 closed depth contours over about 111 acres, and half of that water sits inside the 40 ft line. The 87 ft figure is a single recorded sounding rather than a closed contour, so the deepest line you can actually trace on the map is 80 ft.
Where is the deepest part of Derby Lake?: The deepest charted water on Derby Lake lies inside the 80 ft contour, toward the western side of the lake. That contour encloses 6.6 acres, 5.9% of the mapped water, so it is a small target on a small water, the depth chart above gives the contour to line up on.
How much of Derby Lake is shallower than 40 feet?: About half. The 40 ft contour encloses 50 acres of the roughly 111 acres inside the outer 5 ft line, so the other half of the water is shallower than 40 feet. The sharpest drop is between 5 and 10 feet, where the mapped water sheds 31 acres.
How accurate is this Derby 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 Derby Lake

Crystal Lake depth map · 70 ft max · 10 mi away
Winfield Lake depth map · 57+ ft max · 14 mi away
Scram Lake depth map · 85 ft max · 16 mi away
Baptist Lake depth map · 65+ ft max · 23 mi away
Lime Lake depth map · 70+ ft max · 26 mi away

Mapped fishing venues near Derby Lake

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

Crystal Lake · 10 mi away
Duck Lake · 13 mi away
North Pier · 13 mi away

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