Story on the state of commuting around Boston

[jbvb]

Today's Globe story noted that auto traffic has increased quite a bit. Fair use quote: "The number of miles driven in Massachusetts increased by 10 percent from the first quarter of 2013 to the first quarter of 2017, from 17.2 billion miles to 18.9 billion miles, according to Inrix, a Seattle-based firm that provides traffic data and analytics. "

https://www.bostonglobe.com/metro/2017/ ... story.html" onclick="window.open(this.href);return false;

The article makes no mention of the T, or any state-level planning to address increasing demand. Alas, 30 years of Governors and legislators who only go near T vehicles for photo ops have left us with a system little changed from 1987, except that the same train, subway, trolley and bus routes are entering downtown with crush loads throughout the rush hours. I don't see much hope of even starting to do anything about it this decade either. I wonder when the frogs (drivers, voters) will notice the boiling water...

[moderators, I posted this as info on overall demand and input to the long-term transit planning we aren't doing. If not rail-related enough, I won't mind your removing it]

jbvb

[ThinkNarrow]

By way of comparison, North Station and South Station total 1.9 million passengers per year (source Wikipedia). Ikebukuro Station in Tokyo has 2.7 million passengers per DAY (source Wikipedia). Yes, Tokyo is much bigger than Boston, but not more than 365 times bigger. The lesson is that Japan has a much more rail-oriented view of commuting and has panned and bluilt accordingly.

[Leo Sullivan]

I think it would be nice if "Thinknarrow" re-read the articles that he quotes and also notes that the
totals for Ikubukoro station include the attached metro station. I think he will find that over
120,000 commuter rail passengers a day is pretty good for a system in a city of Boston's size.
I think he will also find that Ikubukoro Metro total is far less than the all mode total.
How about comparing Boston's commuter rail with a similar size european system. That will surprise him.
Please compare metro to metro and Commuter rail to commuter rail and, check the figures.
LS

[ThinkNarrow]

I apologize to Mr. Sullivan, as my statistics were indeed a bit misleading. According to Wikipedia, the breakdown of the 2+ million daily passengers at Ikebukuro is roughly 500K each for the JR, Seibu, Tobu, and Metro lines. The commuter and subway totals for BON and BOS combined are 111k, close to the 120K that Mr. Sullivan cites. If he has some statistics for comparing European stations and Boston stations, they would be an interesting addition. I only mentioned Ikebukuro as it is a station with which both I and jbvb are familiar.

[Leo Sullivan]

All this stuff is on the internet. Look for MBTA ridership statistics, The MBTA Blue Book, and other sources.
The official annual ridership for MBTA commuter rail in 2013 was 35,323,276. this is probably within 2-3%
of the actual total (either way). This does not include the about 42000 weekday passengers boarding at the
North and South Station Red, Green, Orange and Silver Line stations, just commuter rail.
There are all kinds of sources and, you can find out most of this kind of thing at your own computer.
Philadelphia is called SEPTA, Berlin is BVG, Manchester is Manchester Metro etc.
People get too excited when they want to slam the "T" and, they miss some really interesting
information and a shot at real knowledge.
LS

[BandA]

128 is like an iron wall during "rush hour". Actually, on the Mass Pike the peak congestion has moved west, and is now in Natick or Framingham, with slightly less congestion at Weston. Commuter rail is the obvious solution to relieve congestion, but with BOS at "capacity" and BON congested and close-in fares higher than cost of driving CR isn't carrying it's weight.

It would be interesting to compare 93, 95 and 128 rush hour passengers per lane vs CR passenger max capacity per track.

[deathtopumpkins]

It would be interesting to compare 93, 95 and 128 rush hour passengers per lane vs CR passenger max capacity per track.

The theoretical maximum capacity of one freeway lane is 1900 vehicles per hour.

So from that, looking at a random point on the Pike for example (3 lanes inbound), 5700 vehicles can pass in 1 hour. Assuming a generous 1.5 people per vehicle, that's 8550 people.

On the CR, I'd say one bilevel can fit max 200 people (assuming a crush load of standees). An 8 car set would thus hold 1600 people (comparable to some rush hour PVD and WOR trains, IIRC). To get the same capacity as the Pike therefore you'd need to run at least 6 8-car bilevel trains per hour.

[ezcheez]

The theoretical maximum capacity of one freeway lane is 1900 vehicles per hour.

How is this calculated? What speed of vehicles is being assumed? At what capacity does a freeway become saturated?

[rmccown]

A bit of digging comes up with this page

https://www.fhwa.dot.gov/ohim/hpmsmanl/appn1.cfm" onclick="window.open(this.href);return false;

I was told there would be no math test today.

[Disney Guy]

There are certain sections of 128/I95 that I used to breeze along as late as 3:30 PM ten years ago that now often grind to a halt around 2:30 PM

I did some studying of transportation engineering in an earlier lifetime and the number they usually threw out for preliminary highway planning was 1800 vehicles per hour per lane. There is an ancient formula for traffic flow at signalizaed intersections called Greenshield's formula that has a few versions centering on 2 seconds per vehicle per lane after the frst few get going after the light turns green. Two seconds per vehicle equals 1800 per hour. That was back in the days when most vehicles were "full sized" according to rental car agencies. The number could be increased somewhat given a larger number of smaller cars today thus yielding the 1900 vehicles per hour.

I don't like the idea that General Electric chose to build a headquarters in the seaport district. Horrible commute unless you want to live in an apartment or condo. unit, or if you are lucky, have a postage stamp back yard for your family. No faster alternative other than perhaps helicopter.

[RenegadeMonster]

What cracks me up is you often hear people complaining about sitting in traffic for two hours who live right along the commuter rail lines. When asking them about why they don't take the train it is because they could "never live by a schedule" and like the freedom to jump in their car and go when ever they want.

Why is that so ingrained in our society. I'd rather take the train than sit / drive in traffic any day.

[BandA]

According to Wikipedia, interstate highway lane width is 12' minimum. According to the state of Michigan, tracks are 14' between centers minimum. So, tracks are either about the same width or perhaps you can have two tracks for every 3 highway lanes. This is apropos since in the case of the Ma$$ Turnpike Extension and Southeast Expressway, it was decided that highway lanes should replace railroad tracks.

Actual rush hour highway counts around here are higher than the theoretical capacity as the roads are operating above capacity, and cars are driving closer together than is safe. On the railroad side, rules & signal systems prevent exceeding capacity.

GE made a pro-streetcar movie in the 1950s illustrating an arterial road city block with bumper-to-bumper cars. The equivalent capacity was a couple of trolleys with plenty of open road. Of course at higher speeds rail vehicles have worse braking than buses, so longer headways are required.

[KevinSun242]

What cracks me up is you often hear people complaining about sitting in traffic for two hours who live right along the commuter rail lines. When asking them about why they don't take the train it is because they could "never live by a schedule" and like the freedom to jump in their car and go when ever they want.

Why is that so ingrained in our society. I'd rather take the train than sit / drive in traffic any day.

For some reason we also have it ingrained in our society that public transit is for poor people. I personally don't mind living by that schedule. Sure beats the hell (and stress of having to deal with other idiots driving) out of rush hour traffic, and I get to do other things while on the train.

[leviramsey]

The theoretical maximum capacity of one freeway lane is 1900 vehicles per hour.

How is this calculated? What speed of vehicles is being assumed? At what capacity does a freeway become saturated?

Speed (at least the sort of speeds seen on freeways) is basically irrelevant for a road capacity calculation. The main variables are

* distance between cars in seconds (think of the driver ed 2 second rule)
* length of cars

Consider a 15 foot car (marginally shorter than a Camry).

At a speed of 20 mph (29 feet/sec), that means that each car effectively occupies a block of 73 feet, so 72 blocks/mile times 20 mph gives 1,440 cars/hour
At 40 mph (59 feet/sec), the blocks become 133 feet, so 40 blocks/mile times 40 mph yields 1,600 cars/hour
At 60 mph (88 feet/sec), the blocks become 191 feet, so 28 blocks/mile times 60 mph yields 1,680 cars/hour
At 120 mph (176 feet/sec), the blocks become 367 feet, so 14 blocks/mile times 120 mph yields 1,680 cars/hour

Basically, doubling the speed nearly doubles the block length, ceteris paribus, which cancels out the speed increase (the same phenomenon basically holds for train capacity, too). There are also empirically observed capacity reductions for additional lanes (because people tend to slow down in order to change lanes) that kick in, especially when you get beyond 2 lanes in a direction.

With the improvement in braking power in cars* over the past several decades, however, the following distances have decreased somewhat (thus effectively making the blocks smaller and increasing capacity).