The 200 Foot Fallacy and other myths told by wake boat proponents

The Water Sports Industry Association promotes the idea that 200 feet from shore is safe. Everyone else studying the impact of enhanced wakes on shorelines and lake bottoms disagrees. Here’s why.

Enhanced wakes will cause damage at 200 feet from shore.

The University of Minnesota has quantified the impact of wake enhanced boats in their 2022 study. This study is considered by regulatory agencies to be the gold standard for measuring wave power.  The study showed that wake enhanced boats create a wake three to 12 times greater than a ski boat depending on distance and slope of the lake bottom.

The “Minnesota Study” indicates that wake boats need to operate at least 600 feet offshore to allow for wave energy to attenuate to levels similar to that of a typical ski boat operating 200 feet from shore.

The water sports industry distracts and deceives with shoddy research and specious claims

The Water Sports Industry Association claims that 200 feet from shore mitigates the impact of wake enhanced boats and no other restrictions are necessary. They cite a 2022 marine industry-sponsored study that asserts wake boat operation can be done with minimal environmental impact only 200 feet from shore. However, this study is deeply flawed.

  • The Industry claims their study is peer reviewed, however not by standard scientific methods. They will not release the names of their reviewers, nor the water condition assumptions. Without this information the study is not repeatable, not peer reviewable, and therefore scientifically invalid.The 2022 industry study was published in the Journal of Water Resource and Protection, a subsidiary of Scientific Research Publishing, considered to be a “pay to publish” organization. The company is headquartered in Wuhan, China.

  • The Industry conclusion that 200 feet is a safe distance was not a direct result of the computer research in the study, but rather referred the reader back to an earlier 2015 study, which concluded that wake boat wave energy was absorbed by the lake bottom, which is our concern.

The 2022 study lacks scientific rigor

  • The 2022 industry study was done via computer modeling. No actual boats were used in the test. The University of Minnesota study referenced above used real boats on a real lake (Lake Independence in Minnesota). 

  • The industry’s 2022 study assumed the wake boats were operating using only 125 and 143 horsepower. Yet wake boats have engine powers ranging from 350hp to 675hp. They obviously chose smaller horsepower boats in this model to minimize the impact.

  • In the industry’s 2022 study, the researchers did not reveal, nor would they make available when requested, their computer assumptions of the makeup of the water. We do not know the water density, salinity, turbidity, etc.

The WSIA makes poor comparisons and flawed arguments

Wisconsin isn’t Georgia: Our lakes don’t compare

The WSIA cites its recommended 200ft restriction in the Georgia statute. However, Wisconsin isn’t Georgia. Wisconsin has over 15,000 lakes, Georgia has 23. Our lakes are predominantly glacial lakes from very small to very large, many are spring fed and most have a natural shoreline. Georgia lakes are mostly large reservoirs with rocky shorelines that can absorb the pounding of these waves. Wisconsin lakes are more similar to Vermont where they are enacting stringent wake sport regulations that will limit wake sports to only 31 select lakes, based on size and depth. (See: Vermont Regulation)

Wisconsin tourists come for our lakes, not big wakes

The industry also claims that more stringent restrictions will impact Tourism and they are correct, but for the very opposite reason. A small percentage of tourists travel to Wisconsin to wake boat, and these expensive toys (averaging $150,00 and can exceed $300,000) are enjoyed by only four percent of boat owners. By contrast, 1.2 million fishing licenses were sold in Wisconsin in 2022, and fishing generates $2.3 billion in economic activity for the state. So everyone who comes to Wisconsin to fish, swim, kayak, and sail are negatively impacted by wake enhanced boating. By restricting the activity to large lakes, we will be the only Midwestern state that has small and medium sized lakes for everyone to enjoy without the dangers and disruption of wake enhanced boating; making our state even more attractive to the vast majority of people who don’t want to experience ocean-sized waves while they recreate.

Industry studies fail to measure the destructive impact of downward propeller wash on lake bottoms

The shallow water is home to many fish and their nests. The photo on the right shows the hundreds of fish nests approximately 400ft from shore on 85 acre Ashippun lake in southeast Wisconsin.

Downward prop wash scours lake bottoms

When a wake enhanced boat operates in a “surf mode” the boat rides in a Bow up manner, plowing the water at 8-12mph in order to create maximum wake. As this occurs, there is significant and strong downward prop wash that drives into the water column. Evidence indicates that this prop wash disrupts bottom sediment and uproots vegetation as deep as 20 feet below the surface.The diagram below shows this “mode”, courtesy of Vermont Lakes for Responsible Wakes

Note that other water activities such as jet-skiing or tubing do not create this downward prop wash, as the boat is level when on a plane for these activities. Additionally, those type of watercraft do not have near the mass nor power of a wake boat filled with ballast and/or fins. The University of Minnesota is coming out in Spring with its Phase II study that will examine the impacts and strength of this downward prop wash.

You don’t need to be a scientist to see the wake of destruction caused when these watercraft make enhanced waves

Notice the powerful downward propwash that is visible as a cone shooting well underneath the water surface.

However, distance from shore isn’t the end of the story.  Wave energy does not dissipate in deep water. Instead, that energy is preserved until the wave comes into contact with either the shoreline and/or lake bottom, where they decimate fish habitats and disrupt sediment.

Even the boat industry studies admit that lake bottom friction, or bottom scrubbing, is what absorbs the energy from these large wakes and that lakes with steep sloping bottoms or drop-offs will absorb more energy (and thus cause more damage) than gradual sloping lakes.

Prop wash from a wake enhanced boat scouring the lake bottom

When a wakeboat passes over shallow water, the impact on the bottom can be devasting. Fish nests and healthy vegetation won’t survive a single pass like the one depicted in this photo.