Tuesday, September 18, 2007

Texas Transportation Institute Report Shows Traffic Congestion In Anchorage, Alaska Less Than National And Group Averages


The Texas Transportation Institute, an adjunct of the Texas A&M University System, has released a report showing that traffic congestion, measured by a series of parameters, is up nationwide. The idea for this post originated from a story posted in the Rocky Mountain News about the findings for the Denver metro area.

Here are some excerpts from their press release introducing the report:

Traffic congestion continues to worsen in American cities of all sizes, creating a $78 billion annual drain on the U.S. economy in the form of 4.2 billion lost hours and 2.9 billion gallons of wasted fuel—that's 105 million weeks of vacation and 58 fully-loaded supertankers.

These are among the key findings of the Texas Transportation Institute's 2007 Urban Mobility Report. Improvements to the methodology used to measure congestion nationwide have produced the most detailed picture yet of a problem that is growing worse in all 437 of the nation's urban areas. The current report is based on 2005 figures, the most recent year for which complete data was available.

{snip}

The 2007 mobility report notes that congestion causes the average peak period traveler to spend an extra 38 hours of travel time and consume an additional 26 gallons of fuel, amounting to a cost of $710 per traveler. Along with expanding the estimates of the effect of congestion to all 437 U.S. urban areas, the study provides detailed information for 85 specific urban areas. The report also focuses on the problems presented by "irregular events" — crashes, stalled vehicles, work zones, weather problems and special events — that cause unreliable travel times and contribute significantly to the overall congestion problem. Worsening congestion, the study notes, is reflected in several ways:

- Trips take longer
- Congestion affects more of the day
- Congestion affects weekend travel and rural areas
- Congestion affects more personal trips and freight shipments
- Trip travel times increasingly are unreliable

Researchers spent two years revising the methodology using additional sources of traffic information, providing more — and higher quality — data on which to base the current study.

The report identifies multiple solutions to the congestion problem that, researchers say, must be used together to be effective. These include:

- Get as much service as possible from existing infrastructure
- Add road and transit system capacity in critical corridors
- Relieve chokepoints
- Change usage patterns
- Provide choices
- Diversify the development patterns
- Keep expectations realistic



The 57-page PDF report, entitled "The 2007 Urban Mobility Report", not only discusses a host of findings and proposed reccomendations, but, beginning on page 36, shows statistical breakdowns for all significant cities in the United States. Cities are not only rated in absolute terms, but can be relatively compared within four different size groups. This additional grouping is helpful to better define the problem, since the largest metro areas, simply due to sheer size, tend to have the greatest congestion problems.

And, probably to no one's surprise, the report shows that the Los Angeles metro area has the greatest amount of traffic congestion in the nation.

While the average person should find this report readable, it is rather detailed and uses a number of terms which may be unfamiliar to the general public. So before discussing Anchorage's numbers, I'll present those most frequently-used terms and definitions.

Three Major Parameters:

(1). Delay Per Traveler: Defined as the extra travel time for an area divided by an estimate of the number of people traveling by a motorized mode during the peak periods (6 to 9 A.M. and 4 to 7 P.M.).

(2). Travel Time Index: Defined as the ratio of the travel time during the peak period to the time required to make the same trip at free-flow speeds (free-flow speeds are defined in this report as 60 mph for freeways and 35 mph for arterial streets). A value of 1.3, for example, indicates a 20-minute free-flow trip requires 26 minutes during the peak period.

(3). Wasted Fuel Per Traveler: Defined as the extra fuel consumed due to inefficient operation in slower stop-and-go traffic.


Four Population Groups:

(1). Very Large Urban Areas: Population 3 million or more.

(2). Large Urban Areas: Population 1 million to less than 3 million.

(3). Medium Urban Areas: Population 500,000 to leaa than 1 million.

(4). Small Urban Areas: Population less than 500,000.


The Numbers for Anchorage:

(1). Delay Per Traveler: National Average 38, Average for Small Urban Areas 17, Anchorage 10. Anchorage ranks 80th in the nation, and the number is significantly less than most other cities in this class.

(2). Travel Time Index: National Average 1.26, Average for Small Urban Areas 1.09, Anchorage 1.07. This number means that the time required for any trip during non-peak hours will require 7% more time during peak hours. Anchorage ranks 76th in the nation, and again significantly less than most other cities in this class.

(3). Wasted Fuel Per Traveler: National Average 26, Average for Small Urban Areas 10, Anchorage 5. With gas at $3.00 per gallon, this has become a higher-interest item. Anchorage ranks 83rd in the nation, and again significantly less than most other cities in this class.

Additional statistics and appendices are available in a larger version of this report, 138 pages in PDF format. Here are a couple of interesting statistics to note. Percentage of Travel Congested In Peak Period: Anchorage only 19%, comparing quite favorably with Atlanta (76%) and San Diego (85%). Traffic Speed Estimates: Anchorage 59.7 mph on freeways, 31.5 mph on arterial streets, comparing favorably with Los Angeles (34.7 mph on freeways, 25.6 mph on arterial streets).

One of the reasons that traffic congestion in Anchorage has not increased as fast as that of other cities is because the Municipality of Anchorage's Traffic Department maintains an aggressive Congestion Mangement program, focusing on congested locations, travel time data, and periodic vehicle occupancy surveys. Mayor Mark Begich has exhibited a strong interest in this area, although execution of some options, such as the roundabouts on Dowling and Elmore Streets, as well as the mishandling of the Arctic Blvd. rehabbing project, have been stumbling blocks.

Anchorage uses the Anchorage Metropolitan Area Transportation Solutions (AMATS) as its vehicle to examine, debate, and propose new solutions. The AMATS Policy Committee is the group that casts a preliminary vote on new projects. An affirmative vote sends the project to the Municipal Assembly for further action. Here's a description of the AMATS Policy Committees's mission:


The Policy Committee has the authority to act on all matters relating to the continuing, comprehensive and cooperative transportation and air quality planning process for the area.

The AMATS Policy Committee consists of five equal voting members: the Commissioner of the Alaska Department of Transportation and Public Facilities, the Commissioner of the Alaska Department of Environmental Conservation or their designees, the Municipal Mayor, and two Municipal Assembly Members. The Chair of the Policy Committee is the ADOT&PF member.

The Policy Committee's responsibilities are:

- Establish the needs and priorities of transportation.
- Direct the preparation and implementation of transportation plans, programs and studies.
- Manage and secure funding to implement the Transportation Program.
- Provide overall direction to the AMATS Technical Advisory Committee and staff.
- Ensure public involvement throughout the AMATS Process.


An affirmative vote on a project by this committee is a necessary first step towards getting a project included in the Long Range Transportation Plan, in itself a necessary prerequisite to obtain any needed Federal funding. The proposed Knik Arm Bridge is one of those projects. Click HERE to view all previous posts on the Knik Arm Bridge project.

However, the fact that Anchorage's traffic congestion problems appear significantly less than the national average should not be used as justification to scuttle the proposed Knik Arm Bridge. The bridge not only represents current growing needs, but is in anticipation of even greater needs in the future. Even if the proposed southern terminus directly into downtown Anchorage is a bad idea, the bridge itself is still necessary.

No comments:

Post a Comment