Another derecho, unusually warm weather in December, increased precipitation and other extreme weather events have brought home the impacts of climate change in Iowa, and by extension, the need to reduce the state’s contributions to the destruction of the planet.
There is much room for improvement; while ranked 26th in overall carbon emissions among the states and territories, in terms of per capita emissions Iowa ranks 12th, just behind Nebraska and ahead of Oklahoma.
The state Department of Natural Resources, in its assessment of greenhouse gas emissions by sector, notes agriculture as the single largest source in Iowa, followed by residential/commercial/industrial fossil fuel use, power plants and transportation. However, while emissions from agriculture and power plants are on a downward trend, transportation emissions are noted to be increasing, largely propelled by diesel highway vehicles — in other words, commercial trucks. I have written previously about reducing carbon emissions through transportation alternatives to automobiles, mostly in regards to trains, but what if there was another alternative sitting right at the margins of the state?
Iowa is the only state bounded by two navigable rivers — the Missouri and Mississippi – both part of the federal Department of Transportation’s Marine Highway program, an initiative intended to reduce carbon emissions and wear to infrastructure mainly brought upon by commercial trucks on highways. While far past its halcyon days of the 1800s, when steamboats ruled the Mississippi, inland waterways and associated industries are still an important contributor to Iowa’s economy, supporting more than 100,000 jobs and $18.7 billion in total output.
Still, there is reason to suggest that Iowa’s river transportation system is not being used to its full potential. The locks and dams that allow ships and barges to move up and down the rivers have been chronically underfunded for decades by margins of up to 65%, resulting in increasing rates of delays and unavailability in recent years. The average age of these locks and dams is also nearly 80 years — around 30 years past their intended design life, further limiting their ability to accommodate the longer barge tows often seen today.
Although they have been overlooked for several decades, barges are considerably more efficient than both trucks and trains in their ability to carry cargo. The equivalent amount of cargo carried by a modern 15-barge tow and tow boat would necessitate six locomotives and 216 railcars, or a whopping 1,050 semi-trailer trucks.
These differences in scale translate to real impacts on fuel consumption, and by extension, carbon footprint. A 2017 report from Texas A&M University found that inland towing via barges on rivers is capable of moving one ton of cargo 647 miles on a single gallon of fuel, compared to 477 miles by rail, and only 145 miles by truck. Per each ton of cargo transported for one mile, the amount of greenhouse gases emitted by truck was found to be nearly 10 times higher than the amount produced by inland towing (trains were found to be much more comparable to barges, only generating about 1.36 times as much greenhouse gases as inland towing).
Barges have proven to be safer than trucks as well. The same report from Texas A&M found that, while the annual average number of fatalities via trucking was more than 4,400 from 2001-2014, the same figure was only six for inland towing.
An immediate concession is that it is also worth taking into account the environmental impact that barges carry with them — including the impacts on water flow and wildlife brought upon by locks and dams, water pollution from marine traffic, as well as the cargo carried by barges, which often include fossil fuels and agricultural commodities produced with their own environmental impacts. Furthermore, it is undeniable that trucks can go most anywhere in the state, while barges are confined to our eastern and western borders.
However, transportation modes are not a zero-sum game — with proper investment in intermodal facilities and port terminal infrastructure such as cranes, it is not difficult to envision scenarios where freight can be carried to Iowa via barge, transported within the state via train, and finally delivered in the “last mile” by truck — or using the same process in reverse for the export of goods out of Iowa — maximizing the use of more energy efficient modes of transportation. Additional investment in intermodal infrastructure for moving cargo of all kinds via barge and rail would allow the state to make more effective use of its natural geographic advantages in river towns such as Dubuque, Davenport and Burlington.
So far, the story of modern transportation in Iowa has largely been the displacement of river traffic with trains, and eventually, by automobiles. However, the current paradigm of automobile dominance is not sustainable, both in terms of financial cost and environmental impact.
The state DOT notes that even though Iowa ranks 38th in population nationally, the state ranks 13th in miles of roadway and fifth in the number of bridges, suggesting an outsized construction and maintenance burden for roads and highways. Even as the deleterious impacts of highways have been well-documented — including traffic fatalities, air pollution, noise pollution, and the destruction of poor and minority neighborhoods — the state continues to pour hundreds of millions of dollars into highway expansions even as there is no evidence to suggest that adding lanes reduces traffic.
Making full use of Iowa’s inland waterways, rather than taking them for granted, could be a useful component in reducing transportation emissions while still contributing to economic growth.
Austin Wu grew up in Cedar Rapids and is a recent graduate from the University of Iowa College of Public Health. In his spare time he has taken interest in local history and urban design, and through this column seeks to imagine a better tangible future in eastern Iowa by taking inspiration from principles of the past. It will appear in the Press-Citizen twice monthly. Follow him on Twitter, @theaustinwu.