A cautionary tale may be unfolding in Brisbane, Australia, where a recently opened toll tunnel (Clem7) is finding traffic well below forecast. The original tunnel was forecast to have average daily vehicle traffic of about 60,000 vehicles. In reality, traffic is about 21-25,000 vehicles, two-thirds below forecast, even though tolls are discounted.
According to the Brisbane Times (May 4, 2010):
"In figures released to the Australian Stock Exchange this afternoon, the tunnel's operator RiverCity Motorway revealed an average of just 21,178 vehicles used the toll road daily.
"The highest number of trips on a single workday during the month was 25,688.
"By the company's own admission, that was "well below the start-up forecast of approximately 60,000 trips per day".
Last month it was revealed traffic decreased 65.15 per cent in the week after the toll was introduced, even with the temporary 30 per cent toll discount."
It's probably too early to know precisely why traffic is so much lower than forecast but the local economy and the size of the city may be factors. Brisbane, while Australia's third largest city, has a population of just 2 million people. That puts it on par with U.S. metropolitan areas such as Cleveland, Cincinnati, Las Vegas, Orlando, San Antonio, or Kansas City.
Smaller and medium-sized cities will need very high traffic densities for relatively expensive capital projects like toll tunnels to fully pay for themselves as independent facilities.