Substantial surface waves generated by powerboats are essential for recreational watersports. A recent study from the University of Minnesota Twin Cities indicates that underlying factors, including propeller thrust and various wave types, might affect fragile lakebed ecosystems.

Researchers at the University of Minnesota’s St. Anthony Falls Laboratory expanded on earlier studies to investigate powerboat impacts on lake ecosystems during the 2022 and 2023 field seasons. The lake bottom and the water column are two different places and depths where the researchers used acoustic sensors to measure pressure and velocities. They also collected data on other water quality measures and sediment samples.

The two most prevalent situations of the seven recreational powerboats that are frequently used in Minnesota’s lakes and rivers were the primary focus of the researchers’ evaluation. Displacement mode is recommended for leisure cruising on non-wakeboats, while planing mode is recommended for cruising. For wakeboats, the semi-displacement mode is designed for cruising and surfing.. The vessels were manoeuvred directly over the measuring sensors five times for each operational state.

Powerboats Disturb Lakebeds and Ecosystems

• The research, published in the University Digital Conservancy, revealed that all powerboats generate water currents and turbulence capable of disturbing the lakebed.
• Increased turbulence from wakeboats can directly resuspend sediments in the water. This may indirectly result in the release of nutrients such as phosphorus from sediment, perhaps stimulating excessive algal growth, which negatively affects lakes.
• All powerboats, whether cruising slowly or planing, should navigate in waters of at least 10 feet in depth to mitigate the effects of hull-generated vibrations.
• Wakeboats should operate in depths of 20 feet or more while surfing to reduce adverse effects on the lake ecosystem.

“For all motorized boats, simply being careful about where you steer your boat and avoiding shallow spots can make a huge difference,” stated Jeff Marr, co-author of the study and associate director of engineering and facilities at the St. Anthony Falls Laboratory within the University of Minnesota College of Science and Engineering. “Staying in deep water when you’re out on the water —  especially when wakeboarding or surfing — is an easy and effective way to enjoy and protect our waterways. Also, give space between your boat and other boaters and the shoreline.”

The fieldwork for the concluding portion of the project will be completed in autumn 2025. This project phase will analyse the distinctions between wind-generated waves and wake waves created by recreational vessels, along with their effects on the lake ecosystem.

Andrew Riesgraf, William Herb, Matthew Lueker, and Jessica Kozarek are the research collaborators from the St. Anthony Falls Lab.

The research was supported by a crowdsourcing initiative at the University of Minnesota, which included more than 200 contributors. The Environmental Natural Resources Trust Fund (ENRTF) allocated supplementary funding in accordance with the recommendations of the Legislative-Citizen Commission on Minnesota Resources (LCCMR).

Original Publication
Authors: Andrew Riesgraf, Jeffrey Marr, William Herb, Matthew Lueker and Jessica Kozarek.
DOI: 10.13020/r7w9-dp20
Article Title: A Field Study of Recreational Powerboat Hydrodynamics and their Impacts on the Water Column and Lakebed
Article Publication Date: 30-Jun-2025

Original Source: https://conservancy.umn.edu/items/6a47c506-6be5-4c8a-9a96-dfea38f23b2f