The Valley MetroRail light rail transit system in the greater Phoenix, Arizona metropolitan area has been in operation now for five years. When it opened for business for all intents and purposes in Jan. 2009, for the 20-mile, 28 station, $1.4 billion so-called “starter” system, average weekday boardings were projected to be 26,000. In 2012, that figure was 43,268. Average daily in 2013 was 43,619.
Looking at the numbers a little more closely, 20 miles of light rail line translates to 40 miles (2 railway tracks x 20 miles/track = 40 miles). At $1.4 billion that works out to a per-mile cost of $35 million (and includes in that the cost of the procurement of rail rolling stock, overhead electrical catenary infrastructure, and a maintenance facility and rail yard to maintain and store the trains).
This compares to the typical per-lane-mile highway construction cost of $25 million. Remember, this is absent vehicle traffic. When factoring that traffic in, the capacity of 1-lane-mile of highway using a travel speed of 60 miles per hour is 2,400 vehicles per hour. A constant traffic flow at that capacity over a 24-hour stretch would equal 57,600 vehicles.
Assuming 75 percent of vehicles contain just a single occupant, over that 24-hour time frame, 43,200 people could be accommodated and rather handily I would add. And, if the remaining 25 percent of vehicles averaged 2 passengers per vehicle, that would add another 28,800 more people to the mix and therefore produces a total of 72,000 highway users. But, it doesn’t matter whether that is over a freeway distance of one mile or 20 miles – the capacity would still be the same. Remember, we’re talking only one direction of travel. Now add another travel lane for vehicles traveling in the opposite direction and another potential 72,000 highway users could be added for 144,000 highway users total.
So, at $25 million per highway lane-mile for construction, at 20 miles this works out to $500 million. With a minimum of two lanes needed over that same distance, the total construction cost is $1 billion. More than likely, less than that optimal 144,000 highway users would realistically travel the typical two-lane highway (with 60 mile-per-hour speed limit) on a daily basis. That’s my take.
In the highway example, what is missing are the costs associated with vehicle purchases. Assuming an average cost of $20,000 per motor vehicle, at 115,200 vehicles (57,600 vehicles over a 24-hour period per direction of travel) this comes out to a total motor vehicle investment of $2.304 billion – and that is on top of the highway construction costs, the cost of which is split among taxpayers or highway users or both. It should be noted, however, that if any of the highway users are commuters, this is going to affect the way in which numbers are counted.
Say, for example, 70 percent of metro highway drivers are commuters. Their vehicles should not be counted twice, but once. So, in reality, instead of there being 115,200 different vehicles in all using the highway over the 24 hours, instead there would only be 74,880 (57,600 vehicles x .3 = 17,280 vehicles + 57,600 = 74,880 vehicles) traversing the highway (2 directions) in question over the course of a single day. At 74,880 vehicles, this would put total vehicle purchase investment at $1.497 billion.
Either way, I would classify such vehicle purchase investment as a highway operational cost and doesn’t include in that the purchase of gasoline and/or electricity. But still.
Using the railway, to accommodate the same number of users, would require 1,800 train-car loads of passengers in a 24-hour period and that’s based on a capacity of 80 passengers per train car. If each trainset consisted of four train cars, which is typical, accommodated are 320 riders. Using 10-minute headways or six trains per hour, at full capacity, moved in that time space are 1,920 riders and that’s per direction of travel. Spread that out over 24 hours (assuming an around-the-clock operation), the travel needs of as many as 92,160 light-rail riders could be adequately met. Realistically, though, since on the Valley MetroRail light rail transit system ridership is roughly forty-three-and-a-half thousand daily, obviously not as many light rail trains would need to be procured. However, if more equipment is ever needed more train-cars/sets could be secured.
Realistically, as well, highway capacity like that mentioned above would typically be handled by four and not two lanes of roadway which doubles construction costs. So, for 20 miles, we’re looking at a construction cost of $2 billion instead of $1 billion.
So, weighing all factors, dollar for dollar, railways go so much farther in terms of handling capacity than do highways, all things being equal.
But the real beauty of this whole conversation is that with the railway versus the highway, the difference in regard to energy/emissions-savings is like night and day. Historically, in this regard, railways have come out on top.
Keeping this in mind, there is very strong interest in building a high-speed (205 mph) rail line connecting Dallas-Ft. Worth and Houston (a distance of 250 miles) and a magnetically levitated train between Baltimore and Washington, D.C. (a roughly 50-mile distance).
Again, roadways versus railways, which is the better value?
– Alan Kandel