Why Airport Lines Don't Make Sense

Responding To "It Doesn't Even Go To The Airport" Whining

One common refrain you hear from anti-transit critics about the pared down Project Connect rail project in Austin is this complaint: that it “doesn’t go to the airport.” Ignoring the fact that many of the perpetrators of this line of attack are engaging in straight up bad faith, this is a flawed statement for a number of reasons — for one, the network is designed to go to the airport (and would have prior to COVID inflation scope cuts), but due budget considerations that leg just isn’t prioritized in the initial buildout. But critically, the focus that many critics and “normies” have on airport connections in transit networks is a bit misled.

Project Connect map with airport priority extension highlighted in magenta

Let me first say that I am a big fan of rail transit airport connections. When I travel to a city in most developed (and even some less developed) countries, I expect there to be robust and easy-to-use connections between the airport and city center. Heck, when I visit Yogyakarta in Indonesia, I take the rail to the city¹. In America, it’s hit-or-miss, but usually workable if you’re willing to ride a bus instead of a train (many Americans aren’t). When I lived in Seattle and during my frequent visits, I looked forward to riding the LINK lightrail to downtown (and everywhere else it goes).

However, one big issue with airport lines is that most airports are located well outside the center of the city. This means you need to build a lot of rail through more sparsely populated areas. Look at the boardings around the downtown core of Seattle for 2024²:

• Westlake 3,187,111

• Capitol Hill 2,382,761

• Symphony 1,325,796

• Pioneer Square 798,113

• International District 1,612,733

Now compare them to the stations around the airport:

• Airport 2,470,264

• Angle Lake 1,440,715

• Tukwila 943,314

• Rainier Beach 480,549

• Othello 708,251

The airport station receives a fair number of boardings, and so does Angle Lake, however Angle Lake likely benefits disproportionately from being the southern terminus of Line 1, which I would argue should discount its ridership a bit because any such terminus would benefit regardless of airport proximity.

Additionally, logic dictates that most of the people using a transit system daily are not going to the airport, simply because the vast majority of us don’t fly daily or even weekly, and a transit system needs to thrive on daily ridership. Without connecting to the actual dense population and commercial centers, the airport leg itself is useless. So it makes sense to prioritize the areas where most people live and work — which in Austin’s case, is the part being prioritized. I also found at least one MIT thesis that found that benefits of airport rail projects are “systematically overestimated³.”

Now, for the other side of the argument, I can absolutely recognize some of the pros of airport connections:

• It’s a disproportionately valuable, if less frequent, trip for most people

• It’s important for tourism and “first impressions”

• It’s just a plain ol’ vibe

However, I do not believe these merit prioritization over core “trunk corridors” that will serve more daily riders, and I do not believe the success of Project Connect hinges on connection to the airport upon launch (although I wouldn’t be against it).

Notes

1. Indonesia in general has surprisingly good passenger rail, in Java at least, which I believe is somewhat of a colonial inheritance

2. Sound Transit Ridership Data https://www.soundtransit.org/ride-with-us/system-performance-tracker/ridership

3. https://seari.mit.edu/documents/theses/SM_NICKEL_PS.pdf