The July 2009 edition of Scientific American included a neat little article that I just finished reading discussing the environmental impact resulting from the choice of material in railroad ties. This wasn’t the first time I’d thought about this subject, but it was the first time I’d seen it discussed from this perspective. Charles Q. Choi’s article, “Working on the Railroad”, compares the impact on the air itself – wood vs. concrete. The parametre was a simple kilometer of track. The production of concrete has been in the news a lot in the last decade for the impact it has on the air. While the concrete is charged with it’s increased volume of chemicals released into the air, the wooden ties are damned for the trees cut to produce the ties in the first place.
Returning to something I was aware of already, the concrete tie outlasts the wooden tie by a very wide margin and the article discusses some of the offset experienced in the much lower replacement rate of the concrete tie. This is of course further amplified by the other hazards associated with the wooden ties, namely the preservative options used on the tie itself. Long after the tie has ceased to be useful for the railroad it remains a toxic item that needs proper disposal.
I know I’ll be thinking more about this subject over the next little while and I may even come back to this post. Perhaps the happy medium is to plant trees alongside the railroad’s right of way laid with steel rails on concrete ties?