Theo_Fidel wrote:Vina,
Its not that simple.
Dam is best option.
Well, it is past the stage of "rational" / "best options" kind of thing anymore. I saw on TV yesterday the kind of drama that is going on in Kerala, it is thoroughly politicized now (there was a dog with a photo of Jayalalitha hanging from it's neck, there was some "effigy" burning, people marching kind of thing). It is beyond that now and it has become a football and "wedge issue" to milk dry for politicos in Kerala.
So, even if you agree with Kerala ("We will give all the water and we will build the dam". note, they carefully avoid talking about the 999 year lease) and bring down the existing dam (which is TN property) , you are just kicking the can down the road some 20 years or so, when the Kerala assembly just passes a resolution dissolving the 999 year agreement and you can do didly squat coz, you dont control the river any more. The key "strategic" thing is control and that is the ONLY way you can enforce the 999 year agreement, in the lack of the rule of the law in this country and shabby adherence to signed treaties and settled law.
How else can you give assurances like "1 crore liability for every person and every acre for all time to come" as demanded by Dileep (funny.. did he demand the same thing from the Idukki dam which is a far larger dam with far bigger reservoir?) .
The way out is NOT to build and store the water in Kerala anymore. The water is yours, so just take the water! All problems solved. One clean neat solution that leaves no scope for any more BS. Kerala of course can build a dam below the existing one if it wants. But once you take the water , the wisdom/rationale of building a new dam is disappears, the existing dam can stand where it is... Just put this thought out on the table and you can see the immediate change in tune from the Kerala politicos and all the "safety" concerns will vanish and sanity will immediately dawn.
But all the same, for a long term (999 year)
physical solution rather than based on "rule of law /treaty" (as existing and what the ideal case should be), I think this could be the way out and will simply deflate the issue.
Vaigai dam on TN side is never filled. Even overflow from Vaigai dam is used to fill the numerous tanks in Ramnathapuram. These dozens of tanks between them have about 6 TMC of capacity. Not a drop ever reaches the ocean.
I am aware of it. In fact, I have seen the giant tank at RS Mangalam and as far as folks there can recall, it hasn't been filled in ages. That is part of the reason why I think storing water in TN is far better. You might need at best a small dam.. The Vaigai, further down Viraganoor, all the interconnected tanks to Vaigai in Madurai & Ramnad if spruced up and put back to use like in the old days (they are mostly empty beds now), it could be a good way to rejuvenate the old tank and lake based localized irrigation systems and solve this problem once and for all.
The point where the two rivers meet is roughly 180 feet below Kumili saddle. Present reservoir freely elevates this water up to a point where it can flow to TN side. Also 80% + of water comes during SW monsoon. Even then in great downpours. Inflows of 10,000 cusecs- 15,000 cusecs are not unknown.
When the dam was built some 1985/1900 that was the way to do it. With modern tunneling methods such as NATM building evacuation tunnels that go 250 feet below the Kumuli saddle through the mountain should be a piece of cake/laddu/sushi . Many dams these days (the Japanese pioneered them ?), have such tunnels just to remove silt from the dam. No need to raise the water above the saddle doing away with pumping/siphon etc.
Also there is limits to the amount of water the valley can handle. Anything above 1500 cusecs causes severe erosion on Gudalur side. Entire roads and bridges have been swept away as the geology and rivers are narrow and not used to such flows. A 7000 cusec flood could easily flood the entire valley.
Yeah. But that is an engineering challenge that can be handled. Maybe get the penstock pipes as close to Vaigai dam as needed., you really dont need to use the existing rivers and water channels on the Theni side, like in the present scheme of things.
Sure, it probably will cost a bit more than just replacing the dam (which will mean a disruption of 5 to 8 years given IST of existing water and irrigation arrangements, got to consider the cost of that as well) , or maybe not .But all the same, it will fix this problem for good.
If it takes some $1b over to 10 years to fix this for good, (assuming some $50 m per KM of tunnel like in Metro rail), some $500m + another $500m should nail this. For a state with TN's size and GDP, this really is nothing much at all.
Point is, you need a different plan from the existing scheme of things. Not that a negotiated settlement with Kerala should be ruled out if sanity returns there, but making plans based on that is unrealistic,it should not even be a plan B, but rather plan D or E. Plan A should be around taking the water out and enforcing the 999 year lease /treaty.
JMT.
