"Flood proof" highway- what about flood proof rail line?

[#Metro]

http://www.brisbanetimes.com.au/national/pms-plans-to-render-highway-floodproof-20110108-19jiy.html

It has prompted Prime Minister Julia Gillard to commission a feasibility study to ensure the major supply route will never again be cut off because of flooding.
''The Bruce Highway was cut and that's why we have commissioned a feasibility study on flood-proofing the Bruce Highway,'' Ms Gillard said.

...

'That feasibility study will be available for the middle of this year and that points to having a road that is flood-proof.''

What about the train line?

[ozbob]

An impracticability as is flood proofing the rail line I would have thought.  Seems like a political response to the situation to me.  In the long term it will be pushed aside.  Floods have been happening as along as I can remember and will continue in the future.  What worries me is the damage being done to the roads by the trucks.  Time to move bulk freight back to rail ...

[Stillwater]

'Flood-proofing' the Bruce Highway is a utopian dream and would be, ultimately, a waste of taxpayer funds.  To build the highway above the level of the current catastrophic flood height would be prohibitively expensive and require funds to be diverted from other worthwhile government projects that would deliver a better return to the community.  In an engineering sense, to construct a super-elevated earth mound for the highway to sit atop would be to build a very long dam wall that brings its own problems in that it would not let the water drain away and would keep the flood level high for months.  Communities thus affected would complain more bitterly than they are at present.  The majority would seem to be accepting of the situation, hard as it is.  The alternative is to build lots and lots of culverts at enormous cost.

Generally, most new major highway works are built to a standard able to keep them open in all weather except a one-in-100 year flood event.  What we are experiencing is a greater than 100-year flood event.  The life of a new road, before major reconstruction is necessary, is about 40 years, so to build it to a one-in-120 year standard would be waste of money.

For 97-98 per cent of the time, drains, bridges, culverts, roads and railways are able to operate or stay open despite all that Mother Nature throws at them.  That's not bad.

For reasons explained, turning the Bruce Highway into what effectively would have to be a dam wall with a road on top could prolong the length of time that a flood event lasts, cause more houses to be inundated by the water held back from the highway and result in unintentional flood consequences in areas away from the road itself.

The Pareto Principal applies. http://en.wikipedia.org/wiki/Pareto_principle

Roughly, this states that pursuit of the final 20 per cent required to achieve perfection in any endeavour can consume as much effort as that required to achieve 80 per cent near perfection.  What price is the community prepared to pay to achieve that final three or four percent operational efficiency for the Bruce Highway in a major flood event?

The community would think twice if things were explained in terms of 'flood-proofing' the Bruce Highway versus the cost of 10 or 11 major public hospitals.  Or a CRR delayed 10 years in order to divert funds to the Bruce Highway to keep it above the level of a flood that is unlikely to come during the life of the roadworks, or in another 100 years (based on the law of averages)?

Indeed, to do so requires the assumption that society should invest in infrastructure that assumes we will be driving conventional vehicles in 100 years time.  Is that where we think it best to invest our collective monies?

[#Metro]

Sometimes I wonder if they could just clear a long strip of land- no trees or anything like that allowed on it.
When it floods, use a boat or a barge. These ideas ("flood proof" roads) would have to be weighed against alternatives
such as mounds and pads to allow large freight helicopters to land in emergencies like this.

Have to say, the Queenslander house on stilts is doing very well given the circumstances.
These 'once in one hundred year" events may turn out to be more frequent I fear. I can't remember a year
when the rail line hasn't been cut by flooding.

[colinw]

The only thing that makes sense is to perform flood mitigation works on road & rail at the worst points, to get more of the railway & road above the 1 in 100 year level.

It would also make sense to perform flood mitigation works at major airports like Rockhampton, to keep air links open in the case of major floods.

Trying to build either the Bruce Hwy or the NCL so that it is entirely flood resistant simply is not going to happen, for the reasons Stillwater has already very well explained.

[ozbob]

Tweet to the PM

Robert_Dow
 
@JuliaGillard Flood proofing the Bruce Highway or the North Coast Rail is not possible. Far more pressing priorities ..

[ozbob]

I think the PM needs to seek out some staffers who have their feet on dry land ...

[Golliwog]

To be honest, I don't think this is a serious proposal. Those in the know, realise how expensive and how possibly detrimental flood proofing something like the Bruce Highway can be (see Stillwater's post) but I don't think the general public will just accept someones word on it. I have noted a large number of letters in the CM from people saying how stupid it is that the Bruce Highway isn't flood proof and how it always goes under. I just see this feasibility study as the government doing this so they can then show how expensive its going to be and hence why they won't do it.

I do however think they could possibly look at making the highway and railway flood resistant (where/if possible) so that it may go under but it won't be too damaged or washed away.

[WTN]

I would question how much flood proofing they want. They might be able to get away with minor flooding, but flooding on an unprecedented scale?

Sometimes I wonder if they could just clear a long strip of land- no trees or anything like that allowed on it.
When it floods, use a boat or a barge. These ideas ("flood proof" roads) would have to be weighed against alternatives
such as mounds and pads to allow large freight helicopters to land in emergencies like this.

Why not use the existing road? Existing streets are already being navigated by boat.

[Gazza]

I reckon the most cost effective option would be to flood proof the airports. Instead of worrying about 100s of Km' s of road and rail, just do the airports, so in times of emergency you can quickly fly supplies in.
As has been said, its a one in 100 year type event...As long as there is some way of getting in and out then the job is done....Being completely cut off is tough, but at least having air access is bearable for the few weeks the flood even runs for.