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Re: Mysterious Electrical Spike Continues To Jolt BART Riders
Author: OldPoleBurner
Date: 03-26-2016 - 17:55
If you are talking actual per hour passenger capacity per BART track, you've understated it substantially. The last BART schedule I saw had jam packed trains on BART's C-line (west of Concord) at five minute intervals (12 trains per hour) during rush hours. As the trackway is currently configured, they could run almost 14 per hour. And if they didn't need to share the Transbay Tube tracks with other services, they could run out of Concord with 24 to 26 trains per hour.
Now, with 70 seated passengers and 30 standees (a typical rush hour load) per car, that's 1000 passengers per 10 car train; 12,000 to 14,000 per hour; and a bit over 30,000 per rush period per track. And just imagine if the TB Tube had separate tracks for each service; Then that could be 65,000 each rush period.
Now compare that to those three lanes. It is said in traffic engineering circles, that passenger loading in each automobile averages 1.2 passengers per vehicle during rush hours. A figure that hasn't much in decades, despite car pool lanes and other incentives. Each lane can safely handle an average of about one vehicle every three seconds, or 1200 cars per hour. Even at that, you better be on your toes, as flow becomes unstable at any busy on ramp. 1500 per hour can briefly happen, but cannot be sustained for long before stop & go congestion results, not to mention the hazards involved in driving closer than braking distance apart.
So, at 1200 cars per hour with 1.2 persons average, that's 1440 passengers per hour per lane. Compared to the current actual performance of one BART lane (west of Concord) at about 12,000 passengers per hour; the capacity of one freeway lane at 1440 per hour, is a pittance. The BART lane's current actual performance is thus equivalent to 8.3 freeway lanes.
Now suppose that BART's C-line and TB Tubes were configured for the maximum that a single railroad track could produce. That's 26,000 passengers per hour per track, or the equivalent of 18 freeway lanes.
That's why they call it mass transit. Even at ridiculous government inflated prices, a single BART track costs about the same as one freeway lane; but with potentially 18 times the productivity per dollar invested. And that's why things like BART are such an obvious NO-BRAINER, even for medium size metropolises.
Now, with 70 seated passengers and 30 standees (a typical rush hour load) per car, that's 1000 passengers per 10 car train; 12,000 to 14,000 per hour; and a bit over 30,000 per rush period per track. And just imagine if the TB Tube had separate tracks for each service; Then that could be 65,000 each rush period.
Now compare that to those three lanes. It is said in traffic engineering circles, that passenger loading in each automobile averages 1.2 passengers per vehicle during rush hours. A figure that hasn't much in decades, despite car pool lanes and other incentives. Each lane can safely handle an average of about one vehicle every three seconds, or 1200 cars per hour. Even at that, you better be on your toes, as flow becomes unstable at any busy on ramp. 1500 per hour can briefly happen, but cannot be sustained for long before stop & go congestion results, not to mention the hazards involved in driving closer than braking distance apart.
So, at 1200 cars per hour with 1.2 persons average, that's 1440 passengers per hour per lane. Compared to the current actual performance of one BART lane (west of Concord) at about 12,000 passengers per hour; the capacity of one freeway lane at 1440 per hour, is a pittance. The BART lane's current actual performance is thus equivalent to 8.3 freeway lanes.
Now suppose that BART's C-line and TB Tubes were configured for the maximum that a single railroad track could produce. That's 26,000 passengers per hour per track, or the equivalent of 18 freeway lanes.
That's why they call it mass transit. Even at ridiculous government inflated prices, a single BART track costs about the same as one freeway lane; but with potentially 18 times the productivity per dollar invested. And that's why things like BART are such an obvious NO-BRAINER, even for medium size metropolises.
