2011 stats here. https://www.fra.dot.gov/Page/P0362
EDIT: and TRAINS multiple track map was from the Jan. 2006 issue, and is available on TRAINS.COM to current subscribers. While not up to current year stats, this will provide a good starting point for your information.
Ricky W.
HO scale Proto-freelancer.
My Railroad rules:
1: It's my railroad, my rules.
2: It's for having fun and enjoyment.
3: Any objections, consult above rules.
FRA site is not easy to navigate. Try various combination of "mileage statistics" or "single Vs multiple track mileage" comes up with nothing.
Cheers
Roger T.
Home of the late Great Eastern Railway see: - http://www.greateasternrailway.com
For more photos of the late GER see: - http://s94.photobucket.com/albums/l99/rogertra/Great_Eastern/
If you are a current TRAINS subscriber, they have a map showing main-line routes with only 2 or more tracks, and the mileage for such.
IIRC the FRA site has stats for the entire mileage in USA, so it would be a simple matter to subtract the multiple-track mileage from total mileage to get the total for single track miles.
FWIW, in my area, only multi-track line is CSX. We have the CSX (ex NYC) Water-level route, (2 tracks), the NS (ex NKP) Chicago line (1 track), EEC (East Erie Commercial, AKA GE Test track, 1 track plus plant and interchanges), Buffalo & Pittsburgh (ex Alleghany RR) line (1 track), WNY&P Meadville Sub (ex Erie RR, 1 track) and the Meadville-Franklin Industrial Track (ex B&LE, PRR & NYC, 1 track), OC&T, (ex NYC & PRR, 1 track each), B&LE (1 track), and 7 abandoned lines (apperant on sight, another 5 only if you know where to look), 3 ex PRR, 1 track each, 2 segments of the old Erie High-line (which, if still used, would actually create 2 double track segments), an old (very old) oil line RR, an old trolly line, 2 old B&LE branches, an old NYC branch, an old B&O branch, and an old narrow-gauge line that served a brick maker and Tannery. (Of course, counting abandoned, you could include 2 of the 4 former NYC water-level route tracks, as CR removed 2 of the 4 tracks. So, skew it a little bit, but not much.) If my area is representative of others, far more single track miles exsist (and did) than multiple-track miles.
I am having a discussion on the RailSimulation.com regarding North American single Vs double track milleage. I claim there is far more single track milleage in North America than double track but unfortunately, inspite of looking, I cannot find a website with support data.Can someone point me in the right direction please?