Cass Lake water levels are affected by the operation of two dams on the Mississippi River. Otter Tail Power Company operates a dam upstream, just below Stump Lake. At the Cass Lake outlet is Knutson Dam, owned and operated by the U.S. Forest Service. The U.S. Forest Service modified the dam during winter 2015-2016 to a fixed-crest rock-arch structure with a gated bypass channel that will increase outlet capacity during high water events.
The Leech Lake Band of Chippewa Indians operates a commercial fishery for Lake Whitefish and Cisco on the Cass Lake chain. A limited subsistence fishery for game species is also allowed for Band members.
A U.S. Environmental Protection Agency (EPA) Superfund cleanup site exists on Pike Bay near the south side of Cass Lake. The EPA has placed a consumption advisory on Lake Whitefish from Cass Lake and Pike Bay due to elevated body burdens of dioxins in this species.
There are currently no special fishing regulations in effect on Cass Lake. All species are managed under statewide regulations.
Present Fish Population Status
The Walleye population of Cass Lake is healthy and is comprised of good numbers of fish distributed among numerous size and age classes. The 2016 gill net catch rate was 16.6 fish per net, slightly greater than the long-term median catch rate (13.1 fish/net). Approximately half of the catch was between 12 and 15 inches. There are a number of strong year classes in the population ranging from age 3 to age 8 and these fish should provide good numbers of eater-sized fish for this year as well as the next several seasons. The catch rate for age-0 Walleye (approximately 6 inches) during fall electrofishing was below average, but given the strength of adjacent year classes and good numbers of fish approaching optimal harvest size, the future of the Cass Lake Walleye fishery remains bright.
The gill net catch rate for Yellow Perch (31 per net) was below the long-term median (47 per net). The number of fish over 8 inches in the sample was much improved over 2015 (2016 = 22%; 2015 = 11%) and the largest fish exceeded 12 inches in length. Anglers continue to find pockets of keeper-sized perch and, albeit with a little bit of sorting, catches of nice-sized fish are still possible.
The 2016 Northern Pike catch rate of 3.7 fish per net was greater than the long-term median of 3.1 fish per gill net. Better than usual reproduction the past several years has resulted in an abundance of small fish (< 24 inches). However, Cass Lake remains a place to catch good numbers of medium-sized fish (22 to 30 inches) in the population and these fish represented 33% of the sample during spring trap netting efforts.
- Zebra Mussel
- Starry Stonewort
Recreational activities such as recreational boating, angling, waterfowl hunting, and diving may spread aquatic invasive species. Some aquatic invasive species can attach to boats, while others can become tangled on propellers, anchor lines, or boat trailers. Many species can survive in bilge water, ballast tanks, and motors or may hide in dirt or sand that clings to nets, buckets, anchors, and waders. Fortunately, completing simple steps can prevent the transport of aquatic invasive species.