One of the strongest arguments in favor of investment in public transit is the role it plays in mitigating traffic congestion. The logic is simple: more train and bus commuters mean fewer car commuters and fewer cars on the road. A recently released working paper from University of California scholar Michael Anderson provides some real data to back this up. In 2003, employees of the Los Angeles County Metropolitan Transportation Authority went on strike, shutting down the cities bus and train services.
The strike, lasting 35 days, provided an ideal natural experiment demonstrating what one of the countries busiest metro areas would look like without transit services. Anderson found that during peak periods, delays caused by traffic on L.A’s major freeways increased by 47 percent or 0.19 minutes per mile. The delays were more pronounced on freeways that parallel major transit lines reinforcing the idea that transit provides a real alternative to car travel for millions of commuters. The working paper estimates that the benefit of transit in terms of traffic reduction for Los Angeles ranges from $1.2 billion to $4.1 billion per year.
