Cass County · Michigan

Diamond Lake

Soundings in feet · 1,041 acres · deepest 64 ft

Where it is

2 miles southeast of Cassopolis

Cass County, Michigan · 41.8976° N, 85.9795° W

One of 4 lakes named Diamond Lake in Michigan. See them all

Directions to Diamond Lake Apple Maps

Directions open in Google or Apple Maps, to the Michigan DNR public access site.

Today on the lake

Updated 14 Oct 2026, 6:23 pm EDT. Get alerts for Diamond Lake

WEATHERTonight: mostly cloudy, 51°F, wind NE 5 to 10 mph. Thursday: showers and thunderstorms, 64°F, wind E 10 mph.

WARNINGSNo weather or fire warnings in effect.

FIRENo wildfires or prescribed burns reported within 25 miles.

BURNINGCampfires and debris burning: check today's status with Michigan DNR.

ALGAENo cyanobacteria detected by satellite on 12 Oct 2026, the latest clear-sky image.

LAUNCHESDiamond Lake: listed open. Michigan DNR record updated 3 Apr 2026.

National Weather Service; National Interagency Fire Center; U.S. EPA CyAN satellite; Michigan DHHS; Michigan DNR. Weather, warnings, fires and satellite refresh when you open the page (checked at most hourly).

Depth map

12 contours, 5 to 64 ft

05810122030404250606364feet

Michigan DNR survey, fetched 7 Oct 2026. Not for navigation.

Size and depth

1,041 acres · deepest 64 ft (measured) · shoreline about 11.0 mi · clarity about 8 ft

Diamond Lake is the largest of the 98 named lakes of 10 acres or more in Cass County. By Michigan DNR survey it is the 4th deepest of the 31 with a measured depth. Its water is clearer than 21 of the other 76 lakes in the county with satellite clarity readings. Its shoreline measures about 11.0 miles along the state outline. About 23% of its area is deeper than 30 ft.

Ranks against Cass County lakes in Michigan hydrography, Michigan DNR lake surveys and Michigan EGLE satellite clarity; shoreline measured from the state outline. How we measure

Getting on the water

1 public access site on Diamond Lake.

Diamond Lake · Cassopolis Field Office · Open

2 ramp lanes · 60 trailer spaces · vault toilet · accessible restroom · Recreation Passport required

Local boating rules, Cass County

Michigan DNR boating access, fetched 7 Oct 2026.

Fishing

Michigan DNR has stocked Diamond Lake 38 times since 1979. The most recent stocking was 46,637 walleye on 2 June 2026. Species stocked: walleye.

38 stockings, 1979 to 2026, log scale

Latest: 2 Jun 2026: 46,637 walleye.

2 Jun 2026STOCKED46,637 walleye

1 Jun 2023STOCKED59,686 walleye

26 May 2021STOCKED34,635 walleye

25 May 2021STOCKED21,508 walleye

5 Jun 2019STOCKED26,187 walleye

4 Jun 2019STOCKED26,187 walleye

Source: Michigan DNR Fisheries, fetched 7 Oct 2026. How we measure

Where the deep water is

Show water deeper than

Measured from Michigan DNR contours. How we measure

Historically recorded species, from records through 1958: black crappie, blacknose shiner, bluegill, bluntnose minnow, bowfin, brook silverside, brown bullhead, golden shiner, johnny darter, largemouth bass, longnose gar, mimic shiner, northern longear sunfish, northern pike, pumpkinseed, rock bass, sand shiner, smallmouth bass, spottail shiner, walleye, warmouth, western banded killifish, white sucker, yellow bullhead, yellow perch. Historic records, not a current survey.

Michigan Fish Atlas.

Water quality

Average water clarity is about 8 ft (Secchi depth 2.5 m, satellite readings 2018–23).

Clarity 8.4 ft of 64 ft

Michigan EGLE satellite clarity, fetched 7 Oct 2026.

Email me about Diamond LakeWhen it is stockedMichigan DNR has stocked Diamond Lake 38 times since 1979, most recently 46,637 walleye on 2 June 2026. 1 stocking so far in 2026.When algae is reported or testedMichigan DHHS has no records for this lake yet. We email when the first one is posted.When satellite sees a bloom startEPA satellite, checked daily, June to October. We email when a bloom first shows on two clear days, not every day it stays. It has not happened in 2026.Any lake in Cass CountyStockings and algae records on every lake in the county. In 2026 so far: 6 emails.

In 2026 so far, these alerts would have sent you 1 email about Diamond Lake: 2 Jun.

Email address

At most one email a week per lake. We email you a link to confirm before any alert is sent; every email has a one-click unsubscribe.

The area around Diamond Lake

25 other lakes of 10+ acres within about 6 miles of Diamond Lake, 4 with a page here (darker blue); 1 public launch in magenta. Sources: Michigan DNR, US Census Bureau.

Nearby lakes with measured depth

Stone Lake50 ft deep · 2.0 mi · Cass County

Paradise Lake50 ft deep · 3.6 mi · Cass County

Donnell Lake60 ft deep · 4.7 mi · Cass County

Chain Lake42 ft deep · 5.3 mi · Cass County

Belas Lake15 ft deep · 6.0 mi · Cass County

Birch Lake Mill Pond9 ft deep · 6.3 mi · Cass County

Michigan DNR survey; straight-line miles.

Common questions

How deep is Diamond Lake?

Diamond Lake is 64 feet at its deepest point, measured by Michigan DNR survey. It covers 1,041 acres.

Is there a public boat launch on Diamond Lake?

Yes. 1 public access site is listed: Diamond Lake.

Is Diamond Lake stocked with fish?

Yes. Michigan DNR has stocked it 38 times since 1979, most recently 46,637 walleye on 2 June 2026.

How much of Diamond Lake is deeper than 10 feet?

About 38% of the lake's area is deeper than 10 feet, measured from Michigan DNR depth contours.