Is there reason for the floods

Gundog · Guru

Is there reason for the floods

Mike Harding · Guru

Just lots and lots of rain I think.

All the dams were pretty high before the recent rains - sometimes nature simply decides to prove who is boss.

Whenarewethere · Guru

Things that don't help is a lot of these areas are basically floodplains and not much higher than sea level.

Shepparton is 116 metres above sea level & a few hundred kilometres inland.

Water can't run away quickly enough. About 600mm drop per km & many obstacles in the way.

Mike Harding · Guru

Whenarewethere wrote:
Things that don't help is a lot of these areas are basically floodplains and not much higher than sea level.

A good point.

Until early August I was camped about 25km west of Mildura directly on the bank of the Murray at an elevation of 40m above sea level. The water there is now 1.5m higher than when I left but it still has a pretty long way to go before it reaches the ocean.

Whenarewethere · Guru

Earlier this year Roseville Bridge flooded (Sydney, 1 of only 3 access roads to the Northern Beaches). Not from below as the catchment is too small to raise the water level even remotely high enough.

So much water ran down the road & pooled on the road's lowest point because the drains were not large enough.

It was basically a good lesson without catastrophic damage other than the odd car, of getting water away quickly enough & if you can't do that, don't build in catchment areas.

86GTS · Guru

We're paying the price for previous generations building towns in flood prone areas.
After this mess gets tidied up its inevitable that it will happen again in the same towns that are affected this time sometime in the future.

-- Edited by 86GTS on Monday 17th of October 2022 06:50:22 PM

Gundog · Guru

I'm sorry most do not have an understanding of the volume of water held behind Locks one to ten and the other weirs I have mentioned, I have a pretty good knowlege the area as Swan Hill is my home town.

If everyone of the locks and weirs we reduced by 50% that would allow the flood waters to enter the Murray River better, currently the Campaspe is backing up and spreading because the water volume cannot enter the Murray, this will be repeated in a couple of days when the flood waters from Goulburn river arrive at the Murray.

The Murray River swollen and outside it banks down stream from Echuca.

Its the commercial interest of water authorities who wont release water because they are not getting paid for it.

Mariner30 · Senior Member

Whenarewethere wrote

Shepparton is 116 metres above sea level & a few hundred kilometres inland..

Shepp is 200 k's or so inland.

The Goulburn Valley is a huge irrigation area, there are irrigation canal crisscrossing the whole area.

It is the food bowl of Victoria.

I think people from Melbourne either forget or don't know where most of their food comes from

We/ you don't really want much to change there or other places in the State

Once in a bluemoon there is huge floods after massive amounts of rain.

It happens.

( l used to spend a great deal of work/play life time in the GV/ north east )

This is the first major flood along since the '93 floods IIRC.

My daughter still lives and works in one of the towns that was cut off by flood waters last friday...we saw her on the ABC moving stock in the background.

Derek Barnes · Senior Member

86GTS wrote:
We're paying the price for previous generations building towns in flood prone areas.
After this mess gets tidied up its inevitable that it will happen again in the same towns that are affected this time sometime in the future.

-- Edited by 86GTS on Monday 17th of October 2022 06:50:22 PM

Australia is very flat and towns are always built next to water courses so they can have water for drinking and agriculture. So its inevitable that there will be floods when it rains heavily. Putting towns far from water sources would be idiotic as well.

watsea · Guru

If one does probability calculation, the probability of a 1 in 100 year flood occurring in a 30 year period is about 26%, in a 35 year period about 30%. These periods are time spans that people can remember and are easily carried in the lifetime of a town.

There are techniques for building homes etc that are flood resilient. Google search Arch Daily flood resilient homes. Or here is QLD govt link for info:
www.qra.qld.gov.au/resilient-homes/flood-resilient-building-guidance-queensland-homes
The flood resilient homes are places that do need attention before and after a flood event.
Preparation of the land and lower areas of the home before the flood arrives. Then some sort of clean up after. No structural damage but a bit of normality back to lives again in a relatively short time.

Possum3 · Guru

watsea wrote:
There are techniques for building homes etc that are flood resilient. Google search Arch Daily flood resilient homes.
The flood resilient homes are places that do need attention before and after a flood event.
Preparation of the land and lower areas of the home before the flood arrives. Then some sort of clean up after. No structural damage but a bit of normality back to lives again in a relatively short time.

So true; I had an architect designed home on the lake at Chipping Norton, an area noted for regular 10 year flooding.

Concrete footings, cement slab, on raised (1m) block, double brick downstairs all power 1.5m above floor level, no plaster on walls downstairs (exposed brick), polished concrete floors covered in Chinese slate tiles (impervious to water) including garages - If the house ever went under, it could be washed down with a fire hose. The house never was flooded whilst we lived there, or I believe ever since.

The downside to the house was the massive expence in having it built - over double the normal cost of building a regular house. Also much too big for an empty nest - (6-bedroom, 5-bathroom).

Rob Driver · Guru

Everyone wants to live by the river but no one wants to be flooded.

Now let us see.

Would it be

Everyone wants to live by the river.

In more recent times town planning has been influenced by greed and profit rather than common sense.

Building streets and streets of new homes where the eaves are all but touching each other and these huge roofs are forming a massive catchment which then has to discharge into what was once a natural waterway, maybe a local creek which a brilliant just out of school civil engineer has turned into a drain.

Floods are caused by rain and this rain is mismanaged whether it is at the dam or at the home level, it all has to be assessed and corrected if possible.

Unfortunately no one wants to pay.

KevinJ · Senior Member

Maybe we need to build these in flood prone areas:

https://www.floatinghomes.ltd.uk/netherlands.html

dogbox · Guru

Rob Driver wrote:

Everyone wants to live by the river but no one wants to be flooded.

Now let us see.

Would it be
Everyone wants to live by the river.

In more recent times town planning has been influenced by greed and profit rather than common sense.
Building streets and streets of new homes where the eaves are all but touching each other and these huge roofs are forming a massive catchment which then has to discharge into what was once a natural waterway, maybe a local creek which a brilliant just out of school civil engineer has turned into a drain.
Floods are caused by rain and this rain is mismanaged whether it is at the dam or at the home level, it all has to be assessed and corrected if possible.
Unfortunately no one wants to pay.

i wonder who will end up paying for damage done ,due to the work done to protect the race course that has diverted water into nearby suburbs

Gundog · Guru

Everyone wants to live by the river.

No that got nothing to do with the current floods.

I would like to point the finger at the Murray Darling Basin Authority, water cannot flow into the River if the river is running outside its banks when flood water arrives from the tributary into the main river.

Its a bit late now but the dills should have released water from all the downstream barriers, to provide system relief which could have lessened the damage to towns like Rochester.

Total miss management of the system.

Mariner30 · Senior Member

Gundog wrote:

Its a bit late now but the dills should have released water from all the downstream barriers, to provide system relief which could have lessened the damage to towns like Rochester.

Thats exactly what direct family and friends in 3 Goulburn River towns were dreading was about to to happenlast week

Yea ( s-i-l )

Seymour ( friends...a lot of )

Nagambie ( Daughter...who'd already been through belly deep floodwaters chasing horses...more friends )

Fortunately the " dills " did not release huge amounts of water from Eildon...as that WOULD HAVE flooded my daughters house as well

Rob Driver · Guru

Pardon the pun but.

They are damned if they do and damned if they dont.

I would assume that the land that is in a flood plain was financially attractive to be suitably large enough to have horses.

Is this not similar to buying near an airport or a quarry.

dorian · Guru

A shift in the wind direction across Sydney is behind the city's record wet year:

www.abc.net.au/news/2022-10-22/sydney-record-wet-weather-2022-due-to-shift-in-wind-direction/101562826