Minnesota DNR fisheries surveys · latest August 13, 2025
Flour Lake FishingAWater-quality grade A
Minnesota DNR surveys at Flour Lake average 1.70 lake trout per unit of sampling effort (CPUE) across 14 surveys. The most recent is a Targeted Survey dated August 13, 2025. Length samples in the latest survey that recorded them ran 7–8 inches. In Cook County, Minnesota, Flour Lake carries an overall water-quality grade of A. Water clarity averages 18.2 feet of visibility, and the lake has public access. The survey figures on this page are Minnesota DNR's own; the water-quality grade comes from EPA Water Quality Portal samples. Neither is a forecast of today's bite.
Species recorded at Flour Lake
9 species on the Minnesota DNR list for this lake. A species on the list has been recorded here; it does not mean it is catchable today or in every part of the lake.
Stocking at Flour Lake
Minnesota DNR publishes a stocking history for this lake — which species went in, how many, and in which years. Read the years: a lake stocked in one year is not necessarily stocked in the next.
Getting on the water
Minnesota DNR lists the public access sites, including ramp type and parking, in the documents below.
Survey results in full
Minnesota DNR surveys at Flour Lake average 1.70 lake trout per unit of sampling effort (CPUE) across 14 surveys. The most recent is a Targeted Survey dated August 13, 2025. Length samples in the latest survey that recorded them ran 7–8 inches.
A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Flour Lake A from EPA Water Quality Portal chemistry, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
14 surveys on file from MN DNR Fisheries. Most recent: 2025-08-13 (Targeted Survey).
Top Species by Catch Rate
| Species | Avg catch rate (CPUE) | Avg Weight |
|---|---|---|
| Tullibee (Cisco) | 13.53 | 1.09 lb |
| Yellow Perch | 2.11 | 0.14 lb |
| Lake Trout | 1.70 | 1.14 lb |
| Walleye | 1.52 | 2.2 lb |
| Green Sunfish | 1.42 | 0.07 lb |
CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE means more abundant in standardized sampling. This is not a weekly bite report.
Length Distributions
Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.
Tullibee (Cisco)
Yellow Perch
Lake Trout
Walleye
From the 2025-08-13 survey
Temperature and dissolved oxygen measurements were collected from the deepest basin in Flour Lake on August 13th, 2025. This was done to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Lake Trout, the most sensitive coldwater species present in this lake (Cisco, also…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Flour Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — FlourFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Flour (1608)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — FlourFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — FlourPublic Water Access Sites · MN DNR LakeFinder
Common questions
What fish are in Flour Lake?
Minnesota DNR surveys at Flour Lake average 1.70 lake trout per unit of sampling effort (CPUE) across 14 surveys. The most recent is a Targeted Survey dated August 13, 2025. Length samples in the latest survey that recorded them ran 7–8 inches. Minnesota DNR lists 9 species for the lake in total. Those are survey results, not a catch report: a net set on one date measures what was in that net.
When was Flour Lake last surveyed?
The most recent fisheries survey on file for Flour Lake is dated August 13, 2025. Survey intervals vary by lake and by species; a gap of several years between surveys is normal and does not mean the record is missing.
Is Flour Lake stocked?
Minnesota DNR publishes a stocking history for Flour Lake. It records which species were released, in what numbers and in which years — the source documents are linked further down this page. A lake can be stocked in some years and not others, so read the years rather than assuming an annual release.
Does the water-quality grade tell me how Flour Lake fishes?
A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality grades Flour Lake A from EPA Water Quality Portal chemistry, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Before you eat what you catch
A water-quality grade is not a consumption advisory. Mercury and PCB advice for Minnesota waters comes from MDH, and it is issued per species and per size class — a lake can grade well and still carry a meal limit on larger predator fish.
Where to stay near Flour Lake
Top-rated places to stay near Flour Lake
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