The Basis of the 12 additional lanes.

Highway planners calculate that about 2000 automobiles per hour per lane can pass through any stretch of highway. Ironically, just when commuters are feeling bogged down in traffic at 35 MPH, that is when the most automobiles are able to traverse that section of highway. Since there is an average of 1.2 people per automobile, roughly the same number of cars as people must move along the highway. Assume that 55% of the daily ridership is peak hours. With rush hour lasting 2 hours, the equation becomes this:

200,000 people * 55% rides in peak hours / 1.2 people per car / 2000 cars per hour per lane / 2 hours = 22.9 lanes

Now we have to half that number to account for the AM and the PM peaks and round it up to the nearest whole number of lanes.

22.9 / 2 = 11.45

11.45 ===>> 12 lanes in each direction.

Next we would need to consider METRO NORTH... NJ Transit... SEPTA... PATH... Amtrak... and these are merely the commuter railroads not all the subway lines.

...and this is only New York. There are Boston, Washington DC, Atlanta, Chicago, Los Angeles, San Francisco to name a few.

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