As I say, I'm guessing because the details are not clear. But Logically the tunnel should enable them to keep the dam half full, then is there is a sudden farming demand for water they can supplement the dam water with the tunnel water.

The problems have been that the dam has been TOO full. There shouldn't be a need to bring water in from elsewhere.

The problem with this plan is that it would be quite expensive for occasional use.

Yes the dam has been too full because of pressure from the rice growers. They feared there would not be enough water for their needs.

I agree it would be quite expensive for occasional use, the real question then is are we seeing a climate change which will convert "occasional" into "regular" or "frequent".?Put another way, are you a believer or a skeptic on global warming?

And the rice growers feared that too much water release

would wash out their crops just as harvest was coming.

There is an obvious climate shift, and huge vested interests want that observable fact to be muddied into doubt and confusion.

"There is an obvious climate shift", this is the starting point, the unknown factors are how fast and how severe.

The other issue is Bangkok, if all this effort and cost is to preserve Bangkok, is it really worth it? Might it not be simpler to relocate the capitol and let the floodwaters flow unobstructed?

As I say, I'm guessing because the details are not clear. But Logically the tunnel should enable them to keep the dam half full, then is there is a sudden farming demand for water they can supplement the dam water with the tunnel water.

The problems have been that the dam has been TOO full. There shouldn't be a need to bring water in from elsewhere.

The problem with this plan is that it would be quite expensive for occasional use.

Yes the dam has been too full because of pressure from the rice growers. They feared there would not be enough water for their needs.

I agree it would be quite expensive for occasional use, the real question then is are we seeing a climate change which will convert "occasional" into "regular" or "frequent".?Put another way, are you a believer or a skeptic on global warming?

Correct. To be precise the dams were kept full at the wrong time and they used the "wrong" definition for "fully filled reservoir". They should have not allowed systematically any flood control dam in Thailand without 20% reserve margin before the middle of October every year. This figure is derived by assuming the total storage from all flood dams within Chao Pharaya catchment is 75billion cubic meters.

During run up to flood period last year there was no serious initiative to curb raising dams levels so that 20% reserve margin could have been preserved by 1st October. The way the the dams were operated appeared as if there was systematic attempt to completely fill up the dams as early as August.