Complaints from other boaters, lake users impetus for change in state law

Before 1994, Kansas boating laws required motorboats with above-water exhausts to have a muffled system and motors with exhaust stacks to have water-induction systems to reduce noise. The law was difficult to enforce, and when the boating laws were rewritten, the regulation on noise was left out.

However, legislation was passed two years ago that readdresses the issue of motorboat noise levels. K.S.A. 32-1120, which went into effect on state waters January 1, 2007, states that “the exhaust of every internal combustion engine used on any motorboat on the waters of the state shall be effectively muffled by equipment so constructed and used as to muffle the noise of the exhaust.” Muffler is defined as “a sound suppression device or system designed and installed to abate the sound of the exhaust gases emitted from an internal combustion engine and which prevents excessive or unusual noise.”

The law specifically states that motorboats shall not be operated on the waters of this state under any condition or in any manner whereby the motorboat emits a sound level in excess of 86 decibels on the “A” weighted scale, when measured from a distance of 50 feet or more from the source of the sound. The standard for measuring sound levels was adopted from those prescribed by the Society of Automotive Engineers.

Kansas’ standard is consistent with boat noise level laws in other states, including Missouri, Colorado, Oklahoma, and Iowa and was put in place to protect the recreation interests of all boaters and lake users. Exhaust noise is the number one cause of complaints against noisy boats and was the impetus for the new law.

So what does this mean to boaters? Most pleasure boats expel exhaust gases through the propeller hub and won’t be affected. By expelling the exhaust below the water’s surface, the problem of noise is eliminated as the water acts as a natural muffler.

However, boats with above-water exhausts are up to four times louder than those with sub-surface exhaust systems. Consequently, these boats must have some form of exhaust muffling. The law prohibits operating a motorboat on state waters if it is equipped with an altered muffler, muffler cutout, muffler bypass, or any other device that continuously or intermittently bypasses the muffler system or that reduces or eliminates the effectiveness of the muffler system. The law does not apply to motorboats officially registered and competing in or while on trial runs 48 hours preceding a regatta, race, marine parade, tournament, or exhibition that has been authorized or permitted by the Kansas Department of Wildlife and Parks (KDWP).

There are several different types of add-on muffling systems available that would still allow high motor performance while keeping noise within the state’s legal standards. All boaters are responsible for ensuring their boats are in compliance. KDWP law enforcement officers, using special sound measuring equipment, may request boats to submit to an onsite test to measure noise level.


Frequently asked questions regarding mufflering