ENTER THE TUNNELLING MACHINE City fix could work on bridge too
HERE’S a thought. The tunnelling machine proposed in Tony Peach’s opinion piece (Talking Point, September 9) as the means to solve Hobart’s traffic problems can be used as a cheaper answer to the Bridgewater crossing, either before or after resolving Hobart’s traffic difficulties. This would also be a practical means of providing a rail crossing to the Eastern Shore.
ICELAND EXAMPLE
ICELAND with a population of 360,000 has many tunnels. The Hvalfjorour tunnel runs underneath the fjord 6km and a depth of 165m below sea level. It has been toll free since 2018 being opened in 1998. Only 5600 vehicles use this each day. Significantly less than the traffic entering Hobart each day. The recent idea of a fifth lane is a Band-Aid and won’t have any impact on the flow of traffic.
With more subdivisions around Hobart, a long-term solution must be implemented, a tunnel will also control the high levels of noise. If we want good infrastructure, we must accept a toll is required like most other cities. If a small country like Iceland can build these exceptional tunnels and make them toll free after a relatively short period of time, surely this is the next step.
Debra Drew
Dynnyrne
BIG POTENTIAL
David Keyes Austins Ferry
TONY Peach’s ideas have real potential. It has been done before around the world, so the construction methodology is well known. Example, the top of busy Nathan Rd, Kowloon, was temporarily removed and excavated for a suburban rail. The details are online.
The issue is there are a zillion sets of traffic lights between the southern and northern ends of Davey and Macquarie
streets. These cater for traffic moving across the CBD and entry and exit to Davey and Macquarie streets. They slow north and south through traffic to a walk. The solution is to eliminate the crossings and lights, and separate the CBD traffic from north/south through traffic.
The tunnels would do this, but there is another approach that needs serious consideration that would be cheaper and less disruptive in construction. The alternative is to provide tunnels that cross under Davey and Macquarie streets. The topography would seem to lend itself to this at several locations, such as Harrington, Murray and Molle streets. Minimisation of loss of street frontage for vehicular access is something engineers would need to keep in mind.
The increased speed at which traffic would move across the city would place stress on northern and southern entry and exit points. At the same time it would create a degree of improvement. The net effect needs to be assessed.
The Brooker Highway is a dog’s breakfast of traffic lights. It is impossible
to reach an average speed of 80km/ h on this freeway. My trials indicate only an average speed of 27km/h is possible between the Railway Roundabout and Elwick. It is a bottleneck that will stymie improved city through traffic. This has to be addressed as part of the overall solution.
Traffic lights will need to be eliminated and replaced with on/off ramps at a lesser number of locations. In some places this will require property acquisitions. Eastern shore traffic congestion requires reconstruction of the Lower Domain Rd and the introduction of a ferry service with supportive infrastructure serving more locations. This all needs to be overlaid with traffic reduction measures such as light rail, bicycle lanes, park and ride, and decentralisation.
BUSINESS CASE MISSING
Frank Davies New Town
SOUTHERN Outlet fifth lane — $35.5m, seven homes demolished and two years’ traffic disruption — high price to pay to save two minutes’ travel from Kingston to Hobart CBD. Where is the business case? Cost/benefit analysis? Tony Blanks Dynnyrne
DIGGING DEEP
THE problem with tunnelling under roads is all the services located under them, but traversing the Hobart Rivulet and another rivulet under the Brooker Highway are also relevant considerations.
However, a tunnel commencing from the start of the Southern Outlet to join below Cleary’s Gate on the Brooker may be viable as this would bypass the CBD.
Tony Peach mentions it would be difficult to obtain the required heavy duty tunnel boring machines. This is not necessarily the case as there are tunnels being excavated in Sydney and Melbourne at the moment so there may be machines available after those interstate projects are completed.
The huge deterrent is the cost for our small population of greater Hobart which equates to about 5 per cent of each of the major metropolises of Sydney and Melbourne.
Anyone with an iota of common sense can see that demolishing homes adjoining the Southern Outlet will not ease traffic congestion emanating from the CBD, which makes one wonder why the government is pursuing this course of action.
Perhaps the government should start with the more pragmatic option of banning street parking on the most congested sections of Davey and Macquarie streets at peak hours in school terms, as the congestion disappear in school holidays. Also pertinent are the planned park and ride services coming on-board from Kingborough which should result in decreased vehicle traffic from the area.
Monica Antel Cambridge