If You Build It, They Will Come...

The planned expansion of Interstate-5 in San Diego County would finally complete the Southern California metropolis. Los Angeles and Orange Counties became wall-to-wall sprawl development decades ago, erasing all traces of their rural heritage and the scenic outdoors. Northern San Diego County, with its quaint beach towns, is tenuously holding on to the last vestiges of agricultural land and breathable open space. But these areas too are rapidly developing. It is no surprise then that I-5, the only north-south route along the coast, is increasingly traffic clogged. The county’s solution? Invest $1.4 billion to expand the freeway from 8 lanes to 12 or 14 lanes along a 26-mile stretch of the north county coast.

2 minute read

March 3, 2007, 4:25 PM PST

By Diana DeRubertis


The planned expansion of Interstate-5 in San Diego County would finally complete the Southern California metropolis. Los Angeles and Orange Counties became wall-to-wall sprawl development decades ago, erasing all traces of their rural heritage and the scenic outdoors. Northern San Diego County, with its quaint beach towns, is tenuously holding on to the last vestiges of agricultural land and breathable open space. But these areas too are rapidly developing. It is no surprise then that I-5, the only north-south route along the coast, is increasingly traffic clogged. The county's solution? Invest $1.4 billion to expand the freeway from 8 lanes to 12 or 14 lanes along a 26-mile stretch of the north county coast.


The county has good reasons for wanting to improve traffic flow in this region. With 10,000 daily truck trips, this is an important corridor for the transport of goods. It is also the main route for recreational travel between Los Angeles, San Diego and Mexico. However, the rush-hour congestion suggests that commuters contribute much of the additional traffic - one wonders just how many of those are driving 30 or 40 miles to work in San Diego.


Should taxpayers bear the burden of those who choose to live far from work and commute long distances by car? This $1.4 billion subsidy for the automobile, likely at the expense of rail and transit, will enhance the region's dependence on car travel. According to the California Air Resources Board, San Diego County is second only to Los Angeles County in many toxic vehicle-related air pollutants like benzene, formaldehyde and particulate matter. The widening of I-5 is not only a subsidy for polluters (commuters) but also a green light for further sprawl development. History shows that the benefits of the proposed highway enhancements won't last long – additional California road supply typically results in an increase in vehicle miles traveled and, ultimately, further increases in traffic.

 

Resources:

SANDAG – San Diego's Regional Planning Agency

I-5 North Coast Corridor

California Air Resources Board - California Almanac of Emissions and Air Quality 2006

California Air Resources Board - Toxic Contaminant Emissions, Air Quality and Health Risk

"Road Supply and Traffic in California Urban Areas" (pdf)


Diana DeRubertis

Diana DeRubertis is an environmental writer with a strong interest in urban planning, a field that is intertwined with so many of today's environmental challenges. Diana received an M.A. and Ph.D. degree in Geography from the University of California at Berkeley, where she specialized in climate change science and policy. She also holds a B.S. degree in interdisciplinary environmental sciences from the University of Pittsburgh.

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