Toll roads could be the solution to traffic congestion in Hobart, according to urban geographer and transport economist Bob Cotgrove.

Mr Cotgrove, from the University of Tasmania, has suggested a western bypass could be used to take traffic around Hobart.

The city is approaching a breaking point, with many of the state’s services crammed into one corner and a number of large CBD developments under way, the future only holds more traffic and more congestion unless something can be done.

The traffic researcher would like to see Southern Outlet traffic diverted around the north of the city.

“It would provide a quick and convenient way of getting around the CBD without being choked,” Mr Cotgrove said.

There have been a number of suggestions to fix the worsening state of Hobart traffic chaos; ideas including mass transit, public transport, more parking and bypasses are all in various stage of consideration.

Tasmanian Infrastructure Minister David O'Byrne says the bypass idea would probably cost too much.

“The existing infrastructure at times is under pressure, but when you look at the cost of the options for a bypass, it's not worth the expense,” he said.

The Opposition's Matthew Groom says something should be done, but toll roads are not the thing.

“We're not about tolls, but what we are about is ensuring that we have an independent plan.,. a long term plan to solve transport problems in Hobart.”

The dolerite bedrock under Hobart means a tunnel would probably not be possible.