Travel Demand Forecasting Class

Posted on by Adam Bejan Parast

This post originally appeared on Orphan Road.

This quarter I’m taking a travel demand forecasting class. It has been very theory heavy but luckily our final project is hands on. The goal of the project is to reduce emissions, total delays and VMT with a hypothetical city. The catch is that we have to do this with as little money as possible and oh by the way population and employment will increase by 50%.

Well today I slaved away in the dungeon, ie the CEE computer lab for a few hours and I got a good way through the project already. We have the authority to control where growth is located. My strategy was to increase the percent of intra-zonal (ie local trips, which are not loaded onto the regional transportation network) by focusing all growth in three TAZ’s one of which was the CBD. I also tried to balance housing and employment so all of the TAZ’s have a good balance. This included the smaller TAZs as well. These strategies are essentially what smart growth is all about. Put people closer together and close to everything they want.

I haven not made changes to the roadway or transit network yet but as you can see below smart growth principles have cut delay in half (even below current levels) and substantially reduced VMT. Emissions did not go down much because cold starts are the major cause of emissions and I didn’t cut down much on this yet.

Base / New / Change / Change%
Benefit:
VMT= 355242 / 249295/ -105948 / -29.82
Delay= 19010 / 778 / -18232 / -95.91
Emission= 0.85 / 0.81 / -0.04 / -4.58

Also look at the difference of intra-zonal trips and average travel times. This approach reduced the average trip travel time from 12 minutes to 5 minutes. Not to shabby! We’ll see what happens when I get the transit network working. I’ll post again when I complete this project.

Base
Total / Intra / Avg Time
HBW = 122673 / 39.81% / 13.08
HBO = 136416 / 64.48% / 8.04
NHB = 170281 / 66.29% / 14.69
TOT = 429370 / 58.15% / 12.12

New
Total / Intra / Avg Time
HBW = 122673 / 56.73% / 6.96
HBO = 136416 / 70.26% / 4.45
NHB = 170281 / 75.62% / 3.77
TOT = 429370 / 68.52% / 4.90

I show this just as an example. This is a hypothetical example and there were a lot of simplifications that went into the model.

In Fact, King County Subsidizes Seattle Buses

Posted on by John Jensen

ECB over at the Slog gave front page treatment to a post from Matt on Orphan Road that claims that Seattle subsidizes King County’s bus operations. In fact, the opposite is true: The rest of King County subsidizes Seattle’s bus service. Seattle has more service hours per the revenue it brings in compared to the other Metro subareas (the subareas are Seattle, East King, and South King).

Matt’s “revenue” figures are fare-box revenue figures — in other words, the money you give the bus driver when you enter the bus. However, the bus system is primarily funded though sales tax receipts. While Seattle gets the most bus service of any subarea, it does not provide a proportionate amount of sales tax receipts. This basic fact, that King County subsidizes Seattle bus service, is the rationale why the 40-40-20 rule exists: That is, 40% of new service hours go to South King, another 40% go to East King, and the final 20% go to Seattle.

Matt’s post correctly illustrates that Seattle bus service is most cost-effective, but the raw numbers also neglect that there are hundreds of thousands of people throughout the county who don’t live in Seattle and who pay for bus service. And frankly, I think when we’re talking about cost-effectiveness or thinking of the word “profit” we’re not in transit-friendly territory. In truth, public transit systems are not always about the most cost-effective routes — otherwise we’d only have buses at peak times and minimal service throughout the rest of the day. And when the entire county pays for transit service, I think it’s fair to expect that much of its population should have some access to it.

Continue reading “In Fact, King County Subsidizes Seattle Buses”

Metro Sub-area Disequity

Posted on by Matt Gangemi

This post originally appeared on Orphan Road.

In a recent STB post, John asked why we don’t just raise fares in Seattle, since that’s where the money is. I’d argue that Seattle is already subsidizing the rest of King County’s bus service to a large extent.

A few notes from 2007 ridership data:

West area revenue: $55.6M
East area revenue: $10M
South area revenue: $19.8M

West area fare/expense: 25.7%
East area fare/expense: 14.4%
South area fare/expense: 19.6%

Ordering routes by fare recovery looks almost like the original bus route list back when streetcars were removed, with four Seattle routes actually making over 50% farebox recovery. The average farebox recovery for the West side off peak is 24% – that’s almost as high as the system-wide peak recovery (25%).