Light rail advocates often compare a freeway to a rail track, claiming that a rail track can carry more traffic at less cost in less space than a freeway.  This is wrong in general, and true only if one compares the most heavily patronized heavy rail system (New York City) with a least utilized freeway.

            The best way to avoid such selectively biased statistics is to utilize the most broadly based available national averages.  For rail and roads these are the seminal annuals: Transit Profiles and Highway Statistics.  The comparison is best made in terms of AVERAGE DAILY TRAFFIC, the number of persons passing a given point on a track or freeway lane per average weekday.

Freeways 1.  National Average(US DOT "Highway Statistics", 1996, Table HM-72)

            US Avg. Daily Vehicle Traffic on Fwys            14,179  veh/lane/day

            US Avg Veh Occ.  (US Census, 1995NPTS)             1.59     persons/veh

Together these give

            US Avg. Avg Daily Traffic (ADT),            22,544   persons/day/lane

Freeways 2, Orange County (Ref: “1995 California State Highway Log, District 12)

            Orange County Freeway Lane Miles    1480.3         ln-mi

            Orange County Freeway DVMT            28,892,000  veh-mi/day

            Orange County Freeway ADT            19,518         veh/day/ln

            Orange County Freeway AVO            1.17             ps/veh    *(Source CALTRANS)

            Orange County Freeways ADT    22,836         persons/day/ln

Light Rail (US DOT "Transit Profiles", 1996 )

            Annual person-miles            858.4 mill. pers.-mi/yr

            Annual "unlinked" trips            249.2  mill. trips/yr

            Avg weekday unlinked trips        0.8     mill. trips/day

            Directional route-mi of track    562.7 track-miles

    Together, these give:

            US Avg Light Rail ADT,             4897 persons/day/track.

In other words,  the average freeway lane carries a traffic equivalent to 4.6 average rail tracks.  So a valid comparison of average person carrying capacity  based on these broadest possible averages is:

One-US avg directional rail track   »   1/5 of a one-directional freeway lane.

One 8 lane US Avg freeway          »   40 parallel  rail tracks.

A light rail track is the same width as a freeway lane, 12 ft.  The average rail system is not only far more expensive,  but also requires far more right-of-way than freeways for the same person moving capacity.