How To Prevent The Next Flood

[jackr]

Dig a big ditch

+ a network of smaller ones from main catchment areas, like a river system. Listen to the King.

That and on 'How To Prevent The Next Flood'; simply do not hoard water when a heavy monsoon season is upon. It doesn't require Dutch, Swiss, Indian, Lunar, Martian, Zeta Reticulan 'experts' to tell us that.

[smiling mantis]

[What is it about this salt thing chaps ??? The quantity of salt you would need to alter the density of the water would be so huge you would probably need stockpiles as big as the flooded are itself. However lets come back to a guiding principle here and its momentum as the previous poster identified. Momentum = mass x velocity.

So lets say you are able to physically increase the mass of the water flowing by adding salt which as above you cant do due to physical constraints but lets say you do. Against a defined force i.e the water pressure exerted against the water flowing then an increased mass of water would only result in a lower velocity....

This strikes me as counterintuitive somehow, but intuition doesn't make for good argument, so I'll dispense with the water chemistry business.

Ok first what is the scenario we face as it pertains to next floods scenario

1) Bangkok is built on a natural river delta basin at sea level.

2) Thailand rivers are subject to seasonal flooding due to monsoonal variances

3) Allot of the natural canal and drainage pathways that were in existence have been plugged up

4) Water travelling through the north is also subject to collection points for rice irrigation purposes

5) Deforestation in natural catchment areas in the north has contributed to excessive water run off

6) Current drainage arrangement can probably handle unseasonal heavy rains in the Bangkok delta area but not when combined with huge monsoonal deliveries up north.

So solution would be to build a array of inland seas via viaducts that stem off the main flow lines of monsoonal rains... these inland seas are located well up north and are basically like big diversionary ponds interconnected with canals and control gates... The purpose of these ponds which would need to be numerous and large is to basically channel any huge monsoonal dumps. The water could be stored there and via series of sluice gates drained back into the main rivers and tributaries in such a manner that it doesn't casue appreciable flooding.

Some degree of aqua culture based industries could be established in some areas as well.

If the down stream geographical and political networks are never going to handle massive floods like this ( which i don't think they ever will do) then the idea is to alleviate serious monsoonal flooding up towards the source and perhaps do something useful with it.

Cost would be enormous of course but then so is cost of flooding.. potential to employ displaced farmers and villages in maintenance of ponds/ aqua cultural industries etc.

Gut call here is that if you let the wtaer approach Bangkok then there is nothing that can be done effectively.. better to trap or manage the water closer to source.

Rgds monty

Yes this is what theblether suggested above. I like especially the fact that we can find productive uses for the water while its being stored up in this manner, uses that for obvious reasons the addition of large quantities of salt would make impossible. This is like the monkey cheek project proposed by the King, as alluded to by another poster, is it not?

So we're left with known solutions but are supposed to sit silently as they go unimplemented? What am I missing here?

[Soutpeel]

I have got the solution chaps.... easy....have a thousand 400hp tug boats in the rivers and the propellers will push the water out to sea quicker...

[Payboy]

I have got the solution chaps.... easy....have a thousand 400hp tug boats in the rivers and the propellers will push the water out to sea quicker...

Nah, won't work - it will only push the sea further away.

[onionluke]

[What is it about this salt thing chaps ??? The quantity of salt you would need to alter the density of the water would be so huge you would probably need stockpiles as big as the flooded are itself. However lets come back to a guiding principle here and its momentum as the previous poster identified. Momentum = mass x velocity.

So lets say you are able to physically increase the mass of the water flowing by adding salt which as above you cant do due to physical constraints but lets say you do. Against a defined force i.e the water pressure exerted against the water flowing then an increased mass of water would only result in a lower velocity....

This strikes me as counterintuitive somehow, but intuition doesn't make for good argument, so I'll dispense with the water chemistry business.

Ok first what is the scenario we face as it pertains to next floods scenario

1) Bangkok is built on a natural river delta basin at sea level.

2) Thailand rivers are subject to seasonal flooding due to monsoonal variances

3) Allot of the natural canal and drainage pathways that were in existence have been plugged up

4) Water travelling through the north is also subject to collection points for rice irrigation purposes

5) Deforestation in natural catchment areas in the north has contributed to excessive water run off

6) Current drainage arrangement can probably handle unseasonal heavy rains in the Bangkok delta area but not when combined with huge monsoonal deliveries up north.

So solution would be to build a array of inland seas via viaducts that stem off the main flow lines of monsoonal rains... these inland seas are located well up north and are basically like big diversionary ponds interconnected with canals and control gates... The purpose of these ponds which would need to be numerous and large is to basically channel any huge monsoonal dumps. The water could be stored there and via series of sluice gates drained back into the main rivers and tributaries in such a manner that it doesn't casue appreciable flooding.

Some degree of aqua culture based industries could be established in some areas as well.

If the down stream geographical and political networks are never going to handle massive floods like this ( which i don't think they ever will do) then the idea is to alleviate serious monsoonal flooding up towards the source and perhaps do something useful with it.

Cost would be enormous of course but then so is cost of flooding.. potential to employ displaced farmers and villages in maintenance of ponds/ aqua cultural industries etc.

Gut call here is that if you let the wtaer approach Bangkok then there is nothing that can be done effectively.. better to trap or manage the water closer to source.

Rgds monty

Yes this is what theblether suggested above. I like especially the fact that we can find productive uses for the water while its being stored up in this manner, uses that for obvious reasons the addition of large quantities of salt would make impossible. This is like the monkey cheek project proposed by the King, as alluded to by another poster, is it not?

So we're left with known solutions but are supposed to sit silently as they go unimplemented? What am I missing here?

A stick .

edit - might as well make it a molotov cocktail

Edited November 11, 2011 by onionluke