Aquatic Herbicide Permit Rules in Wisconsin
As of September 2026: NR 107 is under active DNR revision. This page summarizes current code and published guidance; confirm anything site-specific with your regional APM coordinator before applying for a permit.
Herbicide is the one removal method in Wisconsin with no small-scale exemption at all. Hand removal has the 30-foot corridor. Mechanical work has the small-waterbody exemption. Putting any herbicide or algaecide into a water of the state always requires a permit under NR 107, no matter how small the treated area is.
What NR 107 covers
Herbicide treatment
Roughly $700 to $900 per acre, sometimes more
Covers coves and larger frontages fast; always needs an NR 107 permit, every season.
Pros
- Fast, covers large areas
- Selective products exist
Cons
- Annual cost, seasonal permit
- Doesn't remove the dead plant material
Best fit: Coves, large frontages, invasive knockdown
NR 107 governs chemical and biological control of aquatic plants and algae, meaning herbicides, algaecides, and biological controls like grass carp. It applies the same way to a homeowner treating a small area at their dock as it does to a lake district treating an entire bay.
Who can apply it
Applying an aquatic herbicide requires either doing it under your own DNR permit or hiring a Wisconsin-licensed aquatic pesticide applicator to do the work. A licensed applicator carries their own state certification for handling and applying chemicals in water, separate from the DNR permit that authorizes the specific project. For most homeowners and lake associations, the practical path is hiring a licensed applicator who also handles the permit application as part of the job; see what to ask a removal company.
Lake-wide vs. shoreline treatment
A single shoreline owner can apply for a spot treatment permit covering a specific nuisance patch, but larger or lake-wide chemical programs almost always run through a lake district or association instead, for a few practical reasons. Larger projects typically need a plant survey first to map what's actually growing before the DNR will approve a treatment plan, and treating an entire bay or lake means coordinating timing with every shoreline owner affected, not just one dock. See how a lake-wide management plan gets approved.
Permits are seasonal
NR 107 permits are issued for a season and expire, so a chemical program isn't a one-time purchase. A lake with an ongoing herbicide plan reapplies and pays the permit fee annually, which is part of why chemical treatment often costs more over several years than a method with a one-time install, even when the per-treatment price looks lower. Full cost ranges are on the cost comparison page.
Applying for a permit
Applications go through the DNR's ePermitting system and require a MyWisconsin ID login, a description of the treatment area and plant species, and the product to be used. Per DNR's published guidance, decisions are typically issued within 10 to 15 business days of a complete application, though survey requirements and a spring rush of applications ahead of boating season can push turnaround toward the longer end. Full decision-tree logic, including how NR 107 interacts with NR 109 for mixed chemical-and-mechanical projects, is on the DNR permit rules page.