Friday, July 7, 2017

Ground Transportation Infrastructure Deficiencies in America - A Growing Problem

A study by the U.S. Department of Transportation clearly shows the sad state of America's ground transportation infrastructure.  In its latest update, the DOT's Conditions and Performance report to Congress provides some interesting statistics that shows where Washington needs to spend money to ensure the safety of the travelling public.  In this posting, we will look at the condition of America's inventory of roads, bridges and transit systems including rail and bus.

Let's start by looking at the condition of America's roads and bridges, key complements of infrastructure that many Americans use on a daily basis.  In the case of roads and bridges, any driver that's ever hit a pothole can tell you that the deterioration of pavement and bridge surfaces can result in increased wear and tear on vehicles.  As well, poorly maintained pavement surfaces can slow traffic, resulting in increased travel time and fuel consumption and increased congestion on alternate routes.  At the time of the study, the national road network included 4,109,418 miles of puce roads and 607,380 bridges.  This network saw over 2.987 trillion vehicle miles travelled including 4.275 million person miles travelled over the year.  Here is a graphic breaking down ownership of the U.S. road and bridge system and the percentage of miles travelled on each:


As you can see, while Federal-aid highways make up only 24 percent of the total length of America's highways and 53 percent of its bridges, it accounts for a whopping 85 percent of total vehicle miles travelled or VMT.

Here is a table that shows the decline of pavement ride quality on Federal-aid highways in the United States between 2002 and 2012:


As you can see, the percentage of Federal-aid highway miles with an acceptable pavement ride quality rating decreased from 87.4 percent in 2002 to 80.3 percent in 2012.  When using vehicle-miles travelled, the percentage of highways with an acceptable pavement ride quality rating decreased from 85.3 percent in 2002 to 85.3 percent in 2012.  The difference between the two measurements suggests that the ride quality on less-travelled Federal-aid highways has declined over the decade as more drivers spend more time on less-travelled alternate routes.

Here is a table that shows the change in the number of structurally sound bridges over the decade between 2002 and 2012:

  
While the number and share of bridges that are deemed to be structurally deficient declined over the decade, there are still 66,749 or more than one in ten bridges that are showing deterioration of primary bridge components and potentially reduced load-carrying capacity.

Let's now look at the condition of America's transit infrastructure.  In this report, the DOT looks at five major transit assets as follows:


The condition of the transit assets are rated on a five category  basis as follows:


Here is a table showing the percentage of each of the five asset categories that received a rating below 2.0 (or poor):


On average, the aggregate condition rating of all nationwide transit assets was 3.5 or "adequate".  The DOT notes that the current investment of $9.8 billion per year on transit infrastructure is completely insufficient to maintain the aggregate rating of 3.5 and projects that by 2032, the condition would decrease to an aggregate average of 3.1.  Additionally, the DOT estimates that it would cost at least $140 billion alone to replace the guideway elements of the rail transit system that are considered in poor condition.


Obviously, the deterioration of America's surface transportation network has suffered significant deterioration over the past decades.  With the federal debt just below the $20 trillion mark, it will be interesting to see how much money the Trump Administration is willing to spend to prevent further infrastructure deterioration, deterioration that is already costing American taxpayers in lost time and damaged vehicles. 

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