The words “green” and “clean” are likely not the first that come to mind when thinking of ground transportation in the U.S. Trucks on the interstate and railroads are probably what come to mind first, but the greenest and cleanest form of ground transportation is one that often gets overlooked: waterway navigation. As the oldest form of transportation, navigation on U.S. waterways is not a new concept. At face value, navigation of the nation’s waterways and environmental sustainability may not seem to be related. Except they are, as navigation has very little negative impact to our environment.