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Canberra Today 5°/6° | Friday, July 1, 2022 | Digital Edition | Crossword & Sudoku

Tram’s bad vibrations over the concrete bridge

Letter writer TIM WALSHAW explains why getting light rail over Lake Burley Griffin is problematic for Commonwealth Bridge.

ALTHOUGH I am not an engineer, I have discussed the issue of getting the tram over the Commonwealth Bridge with a number of structural engineers. 

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In a nutshell, you cannot build a tram bridge out of prestressed concrete, much less connect it to the existing road bridges. 

Why not? Vibration. The concrete will come apart. And if the tram bridge is attached to the road bridges, the vibration will also wreck the road bridges.

The only way to build a rail or tram bridge is to build it all of steel, and not attach it to the road bridges (there is also a separate issue that the gap between the road bridges may not be wide enough for two rail lines). 

A steel suspension bridge is possibly the best solution, though it may sway. 

A Sydney Harbour type is an alternative, as the superstructure would absorb the vibrations. It is not advisable to use a catenary arch for a rail bridge, as it would ring like a bell from the vibrations, and the foundations at either end would not be strong enough to hold it. Alternatively there is the old-fashioned way. Heavy masonry semicircular arches, though that might upset the boaties! 

I am sure the ACT government is discussing the issue of how to build the tram bridge with consultants. However, beware. Consultants have a tendency to give the answers you want, and be a long way away if the advice is wrong. My advice is to obtain well-written indemnities from each of the individual consultants, not the company, for payment of full cost of repair or rebuilding of the bridges. This could be up to $100 million or more. 

In summary, no concrete tram bridges because of vibration. Steel only. After that, select the best option.

Tim Walshaw, Watson

The ‘immorality’ of the tram to Woden

IT seems no member of our elected Assembly is aware of the immorality of the light rail extension to Woden. 

Immoral because the several billion dollars this project will cost (the transport minister has been unable to work out the amount so far) will only be of benefit to some 10 per cent of Canberra’s population, namely those who can afford to live near a rail stop. For the rest of Canberrans it will be a curse. 

For those living in the Woden or Tuggeranong area because the express bus to Civic will disappear – as in the north – and they will be forced to take the tram taking almost twice as long, or buy a car. 

For all Canberrans, regardless of where they live, it will mean a heavy financial debt not just now but for generations to come. Increasingly there will be even less money for essential public services which are in a desperate state already. Some people, like those living in Oaks Estate, don’t even have public transport.

Mr Albanese, could you please teach Mr Barr and friends the long-held principles of the Labor Party? Isn’t one of the most important the care for the have-nots who suffer most when public services are run down as they are here in Canberra?

Robin Underwood, via

Plan puts more basketball courts north 

WOW, $750,000 for another feasibility study, this time to determine whether a $60m development for the Capitals at UC is justified. 

Added to the cost of the four previous studies on indoor sporting facilities over the last 10 years, the ACT government could have funded an indoor community centre for less than the five reports cost!

The last (“Otium Report”) focused only on north Canberra’s basketball needs and suggested that government funding of community courts would impact private operators – presumably Canberra Southern Cross Club and schools, all of which operate commercially. The report did acknowledge a lack of facilities in Gungahlin but nothing came of it. South Canberra did not exist (so far as the report’s scope was concerned).

The UC plan is for a 3500 capacity main court and six other courts. No doubt part of the cost/benefit analysis will be its rental returns based on commercial hire rates and car parking fees, primarily to community groups, despite public monies being used to develop the centre. Pretty good for a campus of 15,000 and one basketball team; and why an additional six courts?

As the Basketball ACT general manager who set up the foundations of the “Team of the Decade”, I have deep affection for the Capitals, but I doubt if any home game sold out in the 1700 seat Convention Centre in the last four years.  

Yes, the Capitals are capable of drawing a capacity house, but only for finals games maybe twice a year. Meanwhile, Basketball ACT struggles to find courts and is turning junior teams away (40 last year). 

The advice from the ACT government is that no funding will be provided for community courts as it expects school gyms to meet such needs (at up to $100 an hour and unavailable at the whim of the school).  

The UC courts proposal will mean that more than 25 courts would be located in Belconnen (including an existing four at the AIS, a two-court complex at UC and two at Radford, which is adding two additional courts, plus two venues seating 4500 and 3500 within two kilometres of each other.  

The rest of Canberra sees three courts demolished in Woden for high-rise apartments and one at the Woden TAFE for hospital expansion and there’s an expectation that the five courts in Tuggeranong will go the same way.

If we are going to have a community indoor sports centre let’s ensure it is located southside and partially funded from the betterment tax should the Canberra Southern Cross Club wish to redevelop its Tuggeranong site for high rise. 

If $60m is available, it can be put to more productive and better located community facilities.

Brian Franklin, former director and GM, BACT (1962-2022).

Tree hollows take a long time

Dr Gina Newton (Letters, CN June 9) is quite right about the value of hollows in old eucalyptus trees.

However, she notes that it takes about 100 years for small hollows to form in eucalyptus trees and 200 years for larger hollows to form. The trees that were the subject of my May 19 letter are probably less than 70-years-old and likely less than 50-years-old, therefore unlikely to have hollows in them of any value.

The tree that features in the photograph that accompanied my letter was a very young tree, perhaps only 30-years-old, and it certainly contains no hollows. I saw no hollows in any of the other dead gum trees in the area.

The fact remains that these dead trees are unsightly and possibly dangerous. In the last few years during strong winds several large branches have fallen. These could injure passers-by. 

Dr Douglas Mackenzie, Deakin

What a great idea!

I RECENTLY heard someone suggest the people with disabilities should become known as people with a different perspective. What a great idea!

Judy Hamilton, Latham

The renewables elephant in the room

I SEE the letter by Robert Brown, Victoria (Letters, CN May17) continues the climate changer party line in displacing coal and gas by renewables. Don’t these people ever think about the elephant in the room with renewables, namely that all renewable infrastructure – the thousands of hectares of solar panels and thousands of wind generators – will have to be replaced every 20-25 years, with expensive maintenance in between to maintain generation efficiency and levels? 

Most of this generation equipment is imported with a great deal from China. God only knows what the world will look like in 20 years’ time but it is not looking good at present with Russia already at war and threatening nuclear war, and China continually threatening to invade Taiwan and who knows where else. 

If climate changers are so keen on getting rid of coal and gas, they had better start thinking about nuclear energy. 

Renewable energy in Australia, despite the hype, will ultimately prove to be unsustainable. That said, there is no real problem with roof-top solar as long as owners are prepared to pay unsubsidised costs and prepared to face full panel replacement costs in 20-25 years, if components are still available. 

Note however, that the value contribution of roof-top solar to the resale value of the home would be minimal or even negative, depending on age. 

There is no getting away from the fact that, irrespective of what sacrifices Australia makes to climate changers, at about one per cent of world greenhouse gas emissions, it can have virtually zero effect on global warming, let alone permanent climate change. 

Max Flint, principal, Australian Logistics Study Centre

Stand up for ‘forgotten people’

I WELCOME “CityNews’” continued attack on the silent ALP/Greens government’s forced public housing evictions and the ironic timely advertisement for World Elder Abuse Awareness Day (both CN June 2), while other articles about the parlous state of my local Liberal Party were justified. 

The topics should be co-ordinated however and my Assembly Liberal team publicly support these 2022 “forgotten people”: the elderly Housing ACT tenants.

 Greg Cornwell, Yarralumla

Good luck with online gambling taxes

IT comes as no surprise that the ACT government wants to introduce a Bill in relation to “online” gambling (, May 31). 

The continued reduction of gaming machines in venues over the years and the restrictions proposed on playing them (, April 29), are ongoing steps of what I believe is the government’s aim to completely remove all such machines from the ACT. 

In addition, wanting to “buy up” machine licences and even paying more for venues to become “pokie free” (, March 18) is further evidence of this.

While gaming-machine control measures may have some limited impact in reducing problem gambling at on-site venues, the result now acknowledged by the government is that “online” gambling simply increases. 

Clearly the government’s now noticed how much tax revenue is being forfeited by the reduction of gaming machines in local venues and more so, how much revenue is now simply going “offshore”.

I for one will be very interested in seeing how the government proposes any Bill on how they will address “online” gambling for taxation purposes. 

With “online” gambling, people can set up third-party linked payment accounts, have anonymity and circumvent blocked websites via the use of VPNs, gamble at any time of day/night and utilise gambling services anywhere across the globe, which are well beyond the reach of the ACT government to send a tax bill – good luck with that.

Bjorn Moore, via email

Robodebt commission a ‘waste of money’

OBVIOUSLY, the new Government Services Minister Bill Shorten has nothing better to do than waste taxpayers’ money on setting up a royal commission into Robodebt. 

What good will it do now that victims have been recompensed to the tune of $1.8 billion after a Commonwealth agreement to a settlement, and the Coalition is no longer the governing body? 

What he should be doing instead is setting up a commission to investigate how the ABC is spending $1.1 billion of taxpayers’ money a year. 

As the ALP and the Greens recently conspired to derail a Senate inquiry into the ABC’s complaints process, primarily on alleged ABC anti-Coalition bias, why are they, together with the ABC, so afraid of an independent inquiry being held if they have nothing to hide? 

Regrettably, it is highly unlikely to happen as it is not in the ALP’s or the Greens’ interest to do so.

Mario Stivala, Belconnen

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