ASPIRE is a quarterly magazine published by PCI in cooperation with the associations of the National Concrete Bridge Council. The editorial content focuses on the latest technology and key issues in the Concrete Bridge Industry.
Issue link: http://www.aspiremagazinebyengineers.com/i/306183
10 | ASPIRE , Spring 2011 P E R S P E C T I V E Yo u h a v e t o l o v e t h e i r o n y — transportation is at a crossroads! Why? Because aggregate demand for individual mobility has rendered the traditional funding mechanism for surface transportation, the federal gas tax, obsolete. Unsustainable best describes this funding mechanism, in its current form, to meet current and future mobility demands. Individual mobility is the freedom of where to go, when to go, and how to go; the challenge to the transportation industry is how best to meet the demand for individual mobility in a financially sustainable manner. "Free" Mobility General highway mobility and the congestion experienced in many areas represent a classic case of economics related to "free" resources. The perception to drivers that driving on highways is "free" causes traffic congestion, with highway capacity being the resource in short supply. It is not difficult to see why highway mobility demand is growing. The individual freedom offered by traditional highway mobility is unmatched in terms of unrestricted arrival/departure times and destinations, scalability to group size, all- weather operation, protection of users from the elements, and accommodation of personal belongings (e.g., groceries or recreational equipment). From this reality, demand management strategies that seek to equate supply and demand via pricing systems represent the best practice for accommodating individual mobility in a financially sustainable manner. Although an increase in the federal gas tax would generate more revenue, it does not permit the establishment of equilibrium between supply and demand that would naturally develop through the use of a pricing system. Cost Versus Benefit Sustainability in transportation has thus far focused almost exclusively on the cost side of the mobility equation. I n c re a s e d e ff o r t h a s b e e n s p e n t recently on discernment of incremental "impacts" to the environment. These are used in part as a means to justify everything from subsidizing transit with federal gas tax revenues, to growth boundaries, and to transit-oriented development (including high-density housing). Nevertheless, the only sane definition of sustainability related to the cost side of the mobility equation is adopting lowest life-cycle costing and asset management methodologies. What about the benefit side of the mobility equation? Is there a way to quantify the benefits of individual mobility? Quantification of the mobility benefit via pricing systems would enable appropriate decision making regarding future expenditures, such as how much capacity should be added and what mode or modes should be advanced. Many fine examples of financially sustainable transportation incorporating pricing systems support the hypothesis that users value their individual mobility highly. So what does financially sustainable individual mobility look like? Selmon Expressway Perhaps the best example of financially sustainable transportation that responds t o i n d i v i d u a l m o b i l i t y d e m a n d i s the Tampa Hillsborough Expressway Authority (THEA) Selmon Expressway in Tampa, Fla. The Selmon Expressway is an important east-west link near downtown Tampa funded entirely with by Kenneth C. Saindon, PBS&J, an Atkins company Selmon Expressway with Tampa, Fla., skyline. Photo: Tampa Hillsborough Expressway Authority. Financially Sustainable Individual Mobility Equating bEnEfits and costs via pricing systEms Book_Spr11.indb 10 3/30/11 5:09 PM