A reader reminds me of this Economist article, arguing that many of the planned high speed rail corridors risk endangering something that's already doing a hell of a lot to reduce our carbon emissions:  our top-notch freight rail system.

The freight railroads have learned to live with the limited Amtrak passenger services on their tracks. Occasionally they moan that Amtrak pays only about a fifth of the real cost of this access. Some railmen calculate that this is equivalent to a subsidy of about $240m a year, on top of what Amtrak gets from the government. Freight-rail people regard this glumly as just part of the cost of doing business, but their spirits will hardly lift if the burden grows.

Their main complaint, however, is that one Amtrak passenger train at 110mph will remove the capacity to run six freight trains in any corridor. Nor do they believe claims that PTC, due to be in use by 2015, will increase capacity by allowing trains to run closer together in safety. So it will cost billions to adapt and upgrade the lines to accommodate both a big rise in freight traffic and an unprecedented burgeoning of intercity passenger services. Indeed, some of the money that the White House has earmarked will go on sidings where freight trains can be parked while intercity expresses speed by.

Federal and state grants will flow to the freight railroads to help them upgrade their lines for more and faster passenger trains. But already rows are breaking out over the strict guidelines the FRA will lay down about operations on the upgraded lines, such as guarantees of on-time performance with draconian penalties if they are breached and the payment of indemnities for accidents involving passenger trains. The railroads are also concerned that the federal government will be the final arbiter of how new capacity created with the federal funds will be allocated between passenger and freight traffic. And they are annoyed that there was little consultation before these rules were published.

There have been some heated meetings between freight-railroad managers and FRA officials. Henry Posner III, chairman of Iowa Interstate Railroad, ruefully notes that freight railroads, in the form of passengers and regulation, "are getting back things that caused trouble".

Moving freight by rail rather than by truck is an enormous carbon saver; one locomotive can haul as much as hundreds of trucks.  It also reduces highway congestion.  Unfortunately, it's hard for passengers and freight to share tracks.  In part, it's difficult simply because it's expensive to upgrade track to handle passenger speeds, but also because freight moves much more slowly, and on an irregular schedule.

I might well argue that if we were simply trying to maximize environmental benefit, we'd ignore passenger rail, and focus on upgrading our freight systems, which sorely need it.  Moreover, these upgrades could largely be made without the massive procedural obstacles that block new high speed rail lines.

But freight rail is not sexy.  It does not excite donors, and it does not excite most of the voters who are motivated by high speed rail.  Politicians win votes by delivering (or at least promising) highly visible improvements; not by silently enhancing the movement of goods from port to Wal-Mart.

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