Friday, December 22, 2006
LA's Orange Line is crumbling
Los Angeles CA - Two news stories, one in the Los Angeles Times and the other in the LA Daily News report that the pavement on the recently opened Orange Line busway in Los Angeles is deteriorating.
The problem is stated to be related to the specifications used in the asphalt mix that paves the 14-mile long busway. Currently there is a lot of finger pointing between the Los Angeles Metropolitan Transit Authority and the contractors.
Between cracks in the pavement and rutting of the surface, the busway surface is in poor shape. Nobody can seem to figure out why the pavement is deteriorating.
I really question the use of asphalt in projects like busways. I am very curious as to why they didn't use cement. Three busways in Pittsburgh were built with cement and there has been little problem with the roadway surface and the busways are holding up well.
The noise factor from tire noise between asphalt and cement in the low to medium speed Orange Line would be minimal. The MTA tried to limit the noise further by paving some sections with a rubberized asphalt coating and found that it only lowered the noise by 2 decibels, a minimal amount that is barely noticeable. The same would be true for cement versus asphalt, a minimal reduction in noise. The busways in Pittsburgh are no more noisy using a cement roadway than they would be with an asphalt roadway.
Asphalt is not really good for applications like busways in my opinion. Sure, it's cheaper in the short term but in the long term, it ends up costing more due to more frequent maintenance and repaving.