What’s That I Hear?

   As the controversy over air traffic and the resulting noise pollution flies on, our industry may want to step back and look within as well. There are sections of the Canyon where the solitude for the boater, hiker and even the rim visitor is routinely broken by over-flights. This solitude is also routinely broken along the river corridor by motor boats.

   Now don’t get your dander up — this is not an anti-motor campaign. I’m a motor boat driver myself and have been for 14 years. Motor rigs account for a hefty percentage of the total user days and provide trip schedules that fill a need. But they do make noise, and maybe more than they need to.

   Since motor rigs aren’t likely to go away anytime soon– and if we are offended by aircraft noise– it seems we should examine our own impact on tranquility as well. But noise reduction is not as simple as it may seem.

   Three main factors work together to determine noise levels. First is the engine itself; a two-cycle engine is inherently noisy because of the reed valve system. Some brands seem to be a little quieter than others, but that has little effect on the other two factors. Second is the boat design; different boat designs have different noise damping or amplification qualities which vary depending on the frequencies generated by the engine. An engine that is quiet on one boat design may not be on another. Third is the operator; generally speaking the operator can make the greatest difference: the more throttle the more noise.

   So the solution is simple: Take the reed valve out of the engine, dispose of the metal frames and break the driver’s arm so he can only turn the throttle half way. But since that probably won’t fly — what will?

   An easy first step is for us drivers to BACK OFF. Think about throttle control when passing another trip or camp. A small reduction in throttle on some boats has a dramatic effect on noise reduction. We owe those we pass that courtesy and a few minutes at a little lower speed shouldn’t effect our schedule.

   The steps beyond that are not as simple although not impossible. As a group we have a tremendous resource base to draw on to attack this problem. Some of you have been working on this issue individually for years. There are engine covers, sound dampening foams, baffles, props, etc. But what items, or combinations of items, really work and are cost effective is not generally known.

   This is where you can come into the picture. If you have worked on this problem, with or without success, let me know what you have done. If we put our collective resources together, hopefully we can reduce our impact on the Canyon and save what hearing we have left. Write with your experience and ideas c/o GCRG or give me a call at (602) 585-6943.

Tom Vail