The National Waterways Foundation (NWF) recently released an updated national study comparing selected societal, environmental and safety impacts of utilizing inland river barge transportation to highway and rail transportation. Titled “A Modal Comparison of Domestic Freight Transportation Effects on the General Public: 2001-2014 (January 2017),” the study was conducted by the Texas Transportation Institute’s Center for Port & Waterways at Texas A&M University.
The study was originally conducted and peer reviewed in 2009 and then was updated in 2014 and again in 2017, when five-year data sets were available. The 2017 update addresses cargo capacity, congestion, emissions, energy efficiency, safety impacts and infrastructure impacts.
In comparing the cargo capacity of trucks, trains and inland river barges, the study found that one common 15-barge river tow has the same capacity as 1,050 trucks and 216 railcars pulled by six locomotives. The study noted that a loaded, covered hopper barge transporting wheat carries enough product to make almost 2.5 million loaves of bread, or the equivalent of one loaf of bread for almost every person in the state of Kansas. A loaded tank barge transporting gasoline carries enough product to satisfy the current annual gasoline demand of approximately 2,500 people.
The study also addressed the amount of cargo currently transported on major rivers and found it equivalent to more than 49 million truck trips annually that would have to travel on the nation’s roadways in lieu of water transportation. In fact, the study showed that the hypothetical diversion of current waterway freight traffic to the nation’s highways would add 1,046 combination trucks to the current 875 trucks per day per lane on a typical rural interstate. The percentage of combination trucks in average daily traffic on rural interstates would rise 14% annually, from the current 17% to 31%.
“While we live in a truly intermodal society, this study’s comparison of rail, truck and inland waterways transportation modes underscores the many benefits of moving cargo by water,” NWF chairman Daniel Mecklenborg said.
Barges are superior in terms of fuel efficiency, according to the study results, which showed that barges are able to move a ton of cargo 647 miles with a single gallon of fuel, up from 616 miles in the last study. Trains move a ton of cargo 477 miles per gallon, while trucks move a ton of cargo 145 miles per gallon.
In terms of safety, the study determined that, after adjusting for differences in cargo quantity moved by each mode, for every one member of the public injured in a barge accident, 80.44 are injured in rail accidents and 824 are injured in truck accidents. For fatalities, there are 79 trucking-related deaths and 21.9 rail-related deaths for every one barge-related death.
The researchers noted that the data for the most recent study on trucking injuries and fatalities varied greatly from previous iterations of the study because the government has changed the way it calculates ton-miles, now examining accidents or fatalities over more ton-miles than previously calculated.
In regard to environmental impacts, the study noted that spills of more than 1,000 gal. are at a very low rate for barges, at 2.12 gal. per million ton-miles, while rail came in at a rate of 5.95 and trucks at 6.04.
The data also showed that the inland towing mode is significantly improving and that inland waterway transport generates far fewer emissions of hydrocarbons, carbon monoxide and nitrous oxide than rail or truck per million ton-miles. On this basis, barges emit 15.6 tons of carbon dioxide, while railroads emit 21.2 tons of carbon dioxide (30% more than barge transportation). Trucks generate 154.2 tons, or 10 times (1,000%) more emissions than barges per ton-mile of cargo moved.
The study results highlight the significant infrastructure impacts that could occur if waterborne freight were diverted to highways.
“Approximately 2 in. of asphalt would have to be added to the pavement of 118,688 lane-miles of rural interstate given the higher levels of expected 20-year truck loadings, assuming an even truck traffic distribution over the national highway system,” the study noted.
Additionally, it said other infrastructure improvements would be required, such as bridges, ramps, highway geometric features like horizontal and vertical curves and shoulders, truck stops, service stations, rest areas, weigh stations and traffic control. Routine maintenance costs associated with the new as well as the existing infrastructure, which would be used more heavily, would likely be significantly higher, the researchers suggested.