Monday, February 16, 2015

Following the tracks of the Empire Builder

Here is a map I put together late last year showing the route of Amtrak's Empire Builder in a way I hadn't seen before. I followed aerial imagery from Chicago to the Pacific Northwest, using different colors to mark out which parts of the route are single-track (red) and which parts have sidings or two or more tracks (yellow). I made it to help shed light on why the train has been plagued by long delays over the past few years, becoming especially bad in 2014. The train usually ranks as the busiest long-distance route in the Amtrak system, but saw ridership tumble nearly 16% to 450,000 in the most recent fiscal year—knocking it out of the top spot for routes of its type and placing it behind the Los Angeles–Seattle Coast Starlight. As work progressed to try and resolve congestion for both freight and passenger service on the line, Amtrak spent several months running the train on a more lax schedule than usual and operating with a partial reroute. Since January 12th, the service is back on its normal route, and on-time performance has improved greatly.

(Note that the map isn't a perfect snapshot—the aerial photography was done at different times for each area, but for the most part it looks like it ranges from being a few years old to only a few months old.)

A combination of several factors led to this trouble over the last few years. The train takes an epic journey of more than 2,200 miles each trip, wending across vast glacial plains and up into a series of mountain ranges before reaching its western endpoints in Portland and Seattle. Between Chicago and Saint Paul, the train runs on tracks owned by Canadian Pacific Railway, while BNSF Railway is the owner of tracks used from Saint Paul on to the west. Both of these are major transcontinental lines for their respective railroads. The route it follows has been hit by extreme weather multiple years in a row, ranging from the "Polar Vortex" to flooding along the Missouri and Souris River valleys, and also a permanent flood that has been slowly raising the level of Devils Lake in North Dakota. Combine that with rebounding levels of freight traffic following the Great Recession, and it became a recipe for trouble. These problems all hit at a time when the railroad began working on significant capacity expansion projects stretching the length of the corridor. Delays from each issue compounded the others and, just like with road construction, the effort to upgrade the line exacerbated delays for all types of rail traffic.

Time for an upgrade

Rail upgrades along the corridor have mostly progressed in a west-to-east pattern over the past few construction seasons, though they haven't all been concentrated in a single spot. One particularly worrying issue for Empire Builder passengers was the deterioration of the line near Devils Lake. BNSF's main line runs diagonally through North Dakota on the Surrey Cutoff (more properly knows as the KO Subdivision) between Fargo and the town of Surrey just east of Minot, but Amtrak has used the line through Devils Lake because it allows access to Grand Forks and its metro-area population of 100,000.

BNSF stopped running their own trains through the Devils Lake area in 2009 and only minimally maintained the track afterward. Amtrak stuck it out a couple years longer despite having to run at restricted speeds. They finally started detouring onto BNSF's main route in 2011 as water lapped at the edge of a bridge by the town of Churchs Ferry. However, the railroad's growing traffic congestion to the west led them to a new agreement with Amtrak and the state of North Dakota where each party would pay 1/3 of the cost to repair and upgrade the Devils Lake and raise the bridge to a level that the lake waters could never reach.

That happens to be on the longest piece of single-track along the Empire Builder route—27 miles—and it's notable how the spacing of sidings widens out on other parts of the Devils Lake line versus BNSF's main line to the south. You can click on the side menu of the map to see an extra layer showing the KO Subdivision (along with a related segment, the Prosper Subdivision).

West of the Devils Lake area, there has also been a major project to add double-track between Minot and eastern Montana, which has been carried out in phases. Initially, some long sidings have been added to the line over the course of a couple of construction seasons, and the final stage will be to connect those sidings together to create a long stretch of double-track. A similar strategy has been at work out in Washington State. You can even see a blurring between old and new imagery of single- versus double-tracking it this spot near Hatton, Washington.

Right-sizing the rail network

It probably seems a bit strange that a major rail route is mostly single-tracked, but as long as trains are scheduled well and the sidings are the right sizes and in the right locations, a single-track line can handle dozens of trains per day. A trade-off is that locomotive engineers have to operate their trains much more strictly than the free-for-all we're accustomed to from driving on streets and highways—a higher level of planning and coordination needs to take place. Trains need need to operate with strict adherence to pre-planned schedules in order to make full use of the line.

Each mile of track comes with an annual maintenance cost of tens of thousands of dollars, so it makes sense to have as little of it as necessary to get the job done—something that all rail companies have learned the hard way. The rail network grew dramatically in the first century of railroading in the U.S., and there were many cases of overbuilding. Some lines were never profitable and ended up being abandoned early on, but the addition of new track outpaced abandonments until the network peaked in 1915. Since then the network has been shrinking due to competition from the automobile and other transportation modes, but we appear to be moving through another inflection point—"Trough Rail", if you will.

Even though railroads have lost a great deal of mileage since the system's peak, the actual volume of traffic has had a decades-long trend of growth. North Dakota has had a spike in traffic due to oil production in the Bakken shale region, but the overall trend has been up for all types of freight including agricultural products and goods shipped in intermodal containers. Remaining rail lines have seen traffic become more concentrated as railroad companies have found ways to make their systems more efficient. However, there's a certain point where there is no more room for efficiency and the rising volume of traffic means that additional track is needed—either replacing old segments that were once torn out or building entirely new tracks.

Many of the major railroads have been making big expenditures to boost capacity, though BNSF has been setting the biggest spending records—$4 billion in 2013, $5.5 billion in 2014, and a planned $6 billion this year. They're expected to slow down after this year, but they're not quite done along the Empire Builder's route yet. There are only a few short stretches of single-track remaining on BNSF's main route through Minnesota, and they'll be spending spending $326 million in the state this year to close some of those gaps, which should be practically eliminated by the end of 2016. The double-tracking project west of Minot will also still be in high gear this year. Amtrak riders may still find some extra time on their hands as they deal with construction-caused slowdowns, but it lays the groundwork for better service for the future. Freight users will be the primary beneficiaries, though at least this fixes one notable gap between Big Lake and Becker that would benefit any extension of the Northstar Line to St. Cloud, or potential added Amtrak service up to Fargo or beyond. BNSF has previously said that they'd need to add some extra track between Minneapolis and Coon Rapids for that to happen, though.

I haven't said anything about the Canadian Pacific track that the Empire Builder uses between Chicago and Saint Paul, but that's mostly just because they haven't been as self-promotional about maintenance and upgrade activities as BNSF. One leg of their transcontinental route west of the Twin Cities also passes through North Dakota, crossing the Empire Builder route in Minot, so they've also dealt with the booming rail traffic in that state. One of their major projects is adding Centralized Traffic Control (CTC) signaling on that route west of the Twin Cities and up to Moose Jaw in Saskatchewan, a process that will take several years.

More on the map

I found it interesting to compare the spacing and length of sidings on the Canadian Pacific tracks to those along BNSF's corridor—they tend to be a bit longer, generally in the range of 2.5 to 3 miles rather than BNSF's sidings which seem to be more like 1.8 to 2.5 miles in length. It's hard to say if that makes a huge difference, though it can allow trains to pass each other at higher speeds, or potentially allow more than one train to fit onto a siding at a time at times of high traffic congestion (freight trains currently max out around 7,000 feet long, so two could fit fairly comfortably on a 15,000-foot siding). That likely gives CP's route a bit more flexibility and capacity than BNSF's typical single-tracked areas, but it's hard to say how much more.

It was a surprise to see that the longest stretch of double-track for the Empire Builder is in Minnesota, stretching 115 miles from the town of Philbrook (southeast of Staples) to Moorhead (just before the line crosses into Fargo). The next-longest segment is about 103 miles from Chicago to the Milwaukee suburb of Pewaukee (I show a segment in Brookfield in red, but that's just because the two tracks split to be half a mile apart for a little bit). The exact length and placement of planned double-tracking in western North Dakota isn't entirely clear, but could end up being even greater than either of those—Minot is 121 miles from Williston, for instance, and that's pretty close to the center of the Bakken action.

There are a couple of major features of BNSF's line that can significantly constrain route capacity going forward—tunnels. The line runs through the 7-mile Flathead Tunnel in western Montana and the northern leg that carries the Empire Builder to Seattle also passes through the 7.8-mile Cascade Tunnel—the longest railroad tunnel in the United States. Each time a train passes through these tunnels, powerful turbines have to fire up to clear them of exhaust generated by the locomotives, and that process can take 20 or 30 minutes. If traffic on the corridor continues to grow, there may be new tunnels in the future, which will be pretty amazing to see.

Final notes

It will be interesting to come back and look at this route again in a few years, to see how things have changed and what the effect has been. The recent decline in oil prices has led to a tapering off of shipments to and from the Bakken region, so the remaining traffic should have a smoother and faster ride than what would otherwise be expected. This should be good news for Amtrak passengers either way.