Judged to Scale

With all the facts and opinions swirling around the TIA, Politifact Georgia has done a great job of fact checking many of the statements offered by supporters and opponents of the referendum.  A full listing of their “Transportation Tax: Truth, Lies and Gridlock” series is here

They recently reviewed the statement that the TIA would add 16 miles of road for every mile of rail and found the statement “mostly true.” (They calculate the ratio as 17.5 : 1).  But what does that ratio mean?  A mile of rail is obviously different than a mile of road; they have different costs, accommodate different numbers of travelers, and serve different needs.  So is a 17 : 1 ratio good or  bad? Beyond the fact checking, the ratio also requires a frame of reference.

According to the Georgia DOT, the ten county Atlanta region currently has 39,900 lane miles of road.  The latest entry in the National Transit Database reports that MARTA has 96 track miles of rail.  Including the under-construction Downtown Streetcar will add another 2.7 miles of rail, for a total of 98.7 track miles in the ten county region.  

Politifact reports that the TIA would fund 21 miles of new rail, a 21.3% increase from the baseline.  Adding 365 miles of road (also Politifact’s number) would increase metro Atlanta’s road mileage by 0.9%. 

Comparing the TIA ratio to the status quo is also an interesting exercise.  Politifact calculates the road to rail ratio for the TIA as 17 to 1.  Using the GDOT and National Transit Database numbers, the ratio for the existing system is 404 to 1. 

So back to the original question – what does 17 to 1 mean? 

It means that the TIA would build rail at a dramatically higher rate than metro Atlanta has historically.  It means that the TIA would fund a significant increase in Atlanta’s total rail mileage and a negligible increase in its total road mileage.  Atlanta’s historical focus on road construction certainly skews the baseline for any road/rail comparison heavily in favor of roads.  But how we have spent money in the past is a necessary reference point in deciding whether the TIA is a step in the right director or simply more of the same.