Employment is low density

Why Does CMT Make Sense?  Consider The Austin Market:
•    Average Home-to-Work Distance, by car, is 12 Miles.
•    Most home to work trips are from one low density area to another low density area.
•    70% of jobs are in low density areas, not in the city center.

In the zip code map below the red numbers are employment, by zip code, in thousands.
There are 50,000 in Central Business District (CBD),
between 300,000 and 450,000 in the rest of the service area and 
880,000 in the Metro Area. 
Major roads are 183 (orange), IH35 (blue) & MOPAC (green)
The central business district (78701 in light green) has 50,000 jobs.
The yellow zip codes in north Austin (78753,58,59) have 54,000 jobs.


Data from : http://www.capcog.org/information-clearinghouse/tabular-data/
Commute and Labor Sheds by Zip Code, 2007



Circulator Vehicle Size By  Zip Code

OFF-PEAK 82 HOUR MAP

Yellow - van every 10-12 minutes.
Orange - van every 5-9 minutes.
Green- Bus with 44 seats every 10 min



152 Circulator routes ranked from highest to lowest ridership.
Graphs below are result of computer modeling.
Inputs are employment, area, population and income for each zip code.
Green curve is the estimated riders per square mile, divided by 100, for each route.
Route 1 has a value of 60 which means 6000 riders per square mile.
Route numbers are along the bottom edge of the graph.
Route 71, is more typical with a value of 8, or 800 riders per square mile.
Purple curve is vehicle capacity.
This shows that taxi vans , with a capacity of 14, will work for
more than 90 % of the routes in the off peak 82 hours of a service week.

Green: Riders per square mile / 100      Purple: Vehicle capacity is 14 or 70
Off Peak 82 Hours/Week


Route 71 has a red curve value of  7 for 7 vehicle trips per hour.
Riders per vhicle trip, the blue line, is 14.
That means almost every taxi van leaving the transit center will have 14 riders on board.
How can it be predicted that every van trip will be full ?
The idea is to wait until the van is full and then go.
If it takes longer than 12 minutes to fill the van then send it , only partly filled , after 12 minutes.
For the routes between 5 and 81 there will be enough riders that it will rarely take longer than 12 minutes to fill a van.
By contrast Route 126 will have only 4 riders per van trip with vans leaving every 12 minutes.

Red : Vehicle trips per hour , range is 5 to12      
Blue : Riders per Vehicle Trip, range is 1 to 60


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