Tsunami expert raises fears over Sethusamudram Canal
Interview with Professor Tad S. Murty

Interview with Prof G Victor Rajamanickam

Prof. Tad S. Murty is one of the most respected Tsunami Experts around the world; he advises the Government of Canada on Tsunamis and had played an important role in the development of the 'Baird' simulation model of the December 26th Tsunami. He was in the Editorial Board of the most prestigious Tsunami Journal "Science of Tsunami Hazards" for many years.

He along with Dr.Arun Bapat, had analysed the Tsunamis of the Indian Ocean in 1999.* He was in India this January to participate in the 'Brainstorming' Session on the Tsunami of 26th December organized jointly by Department of Science & Technology (DST), Department of Ocean Development (DOD), Council of Scientific and Industrial Research (CSIR) and Indian National Science Academy (INSA) on 21-22 January, 2005 at New Delhi. Subsequently, when National Institute of Oceanography, Goa organised a National Workshop on Formulation of Science Plan for "Coastal Hazard Preparedness" on 18 - 19 February 2005, he set the tone for the workshop with his paper titled "Perspectives on Coastal Hazard Preparedness".

The following is an e-mail interview conducted with him by the Editor of this web portal on 7- 11 July 2005. The interview assumes its importance following the July 24, 2005 Nicobar 7.3 R Earthquake that had caused much panic. It also assumes its importance as the Expert Level discussion between India and Sri Lanka on the possible impact of the Sethusamudram Shipping Channel Project on the marine and coastal environments of both the countries is scheduled on 1 August 2005 at New Delhi.

* [" TSUNAMIS ON THE COASTLINES OF INDIA" Science of Tsunami Hazards Volume 17(3), 1999]

Question: Would you please tell me what you personally think about the reply given to the Prime Minister by Tuticorin Port Trust with regard to your critical opinion about the present alignment of the Sethusamudram Shipping Channel published in the Indian Express dated 18 January 2005?

Prof. Tad S.Murty: I would first of all share with you a bit of background on my slight involvement with Sethusamudram Shipping Channel Project.

In January 2005, I was in India as the tsunami expert on the delegation of Prime minister Paul Martin (Canada) visit to various Asian countries following the tsunami. On 18th January I was with the prime minister at a press briefing in Delhi.

Later some Indian express and Telegraph reporters spoke to me about SSCP and I made these comments. Earlier I was working on a paper on SSCP and was interested in the scientific aspects of the project.

In May Tuticorin Port Trust (TPT) sent me a fax dated early February asking for my comments and said that the project is finalized by end of Feb and they wanted my comments within 24 hours. I replied to Mr. Raghunadh (IAS officer) ( read: Mr.Ragupathy - Editor ) that I received his fax only in May and possibly I cannot reply by mid-Feb. I sent a page explaining why the eastern entrance of the channel should be re-oriented.

After a few days I received a reply saying that his experts outright dismissed my idea as ridiculous and has absolutely no merit. I did not do anything after this, as I have no official involvement. If you include my student days in the Andhra University and later at the university of Chicago, I have more than 45 years of experience with tsunamis worldwide and I know what I am talking about.

I cannot understand why Tuticorin Port Trust could not find me when everyone else can find me. The Indian Express newspaper article clearly says that I was staying at the Taj Palace hotel in Delhi and will be there for another week or so. Question: How do you react to Tuticorin Port Trust's statement that the suggestion you had made with respect to the present alignment of the Channel and its possible chance of acting as a conduit to future tsunamis, thus paving way to causing damage to South Kerala coast as untenable? Prof. Tad S.Murty: Tuticorin Port Trust (TPT) of course can draw whatever conclusions they want to. I feel that the Bay of Bengal entrance of the present orientation of the channel will undoubtedly funnel tsunami energy into the channel and this will meet the tsunami traveling from south of Sri Lanka at the southern part of Kerala and through constructive interference will augment the tsunami wave amplitudes. The southern part of Kerala was not much impacted by the 26th December 2004 tsunami mainly because the tsunami that arrived from the Indian Ocean has to diffract around Sri Lanka, which necessarily has to take a very wide turn (because tsunamis are long gravity waves and cannot bend as easily as short waves, just like a big car versus a mini. A mini cut corners, but a big car has to take very wide turns.) and missed south Kerala.

It is very easy to show that the SSCP channel with a depth of 12m will indeed provide another route for the tsunami and the energy will be directed towards south Kerala. I have no official connection with the SSCP, only a scientific curiosity plus my concern that south Kerala will be put at risk in future. I do not worry that TPT does not think much of my ideas or me. I do not have to justify myself to TPT. I have to fight my battles, not with TPT but in the field of peer reviewed international scientific journals.

To summarize, a re-orientation of the eastern entrance of the channel towards northwest will fix the tsunami problem. Why this concerns me is a parallel example in the Alberni canal on Vancouver Island, British Columbia province of Canada. In the March 28th 1964 Alaska earthquake tsunami, outside of Alaska, the largest tsunami amplitude was at the head of the Alberni canal well inland and not at the open coast as everyone expected. Later when I joined the Canadian Oceanographic Service, I explained this as due to quarter wave resonance amplification.

The SSP canal has many characteristics similar to the Alberni canal, and this is the reason I am concerned. Question: The Detailed Project Report prepared by L&T; - Ramboll has finalized the location of the dumping sites for the dredged materials.

They are located in Bay of Bengal and Gulf of Mannar and have a depth ranging from 30 to 40 km. These sites happen to lie just north of and south of the entrance and exit of the channel. What are the chances for these sites to remain safe and stable during the time of a future tsunamis and cyclones? Also, what are the chances for them to be carried over into the channel in the event of future tsunamis and cyclones?

Prof. Tad S.Murty: I need to do some back of the envelope calculations to precisely answer your question, which I will do in a few days. However, my initial intuition is that the dumping sites will not be completely stable, especially if they happen to be in the path of the tsunami waves. They may be relatively stable from the cyclones and storm surges, since these do not cause much bottom scouring like tsunamis. The safety issue arises if they are contaminants, especially radioactive contaminants.

Again, I need to do a back of the envelope type computation for a definite answer, again my intuition is that the cyclone and storm surge effects will be less as compared to tsunamis. Certainly tsunamis have the potential to pull all this material back into the channel, if the orientation is right.

The basic question I will attempt to answer through an analytical analysis is simply this. Would storm surges and tsunamis have the energy to move the dredged material back into the channel? As I said earlier, my present feeling is, storm surges probably will not move much material, but tsunamis definitely would. I will try to quantify this in a couple of days.

As per the TPT's conclusion that no re-orientation of the eastern entrance of the channel is required, I absolutely disagree with it. I do not need to analyze that any more.

I have analyzed I now have more definite answers to your questions.

In spite of what the TPT says, there is a real threat to southern Kerala from future tsunamis from SSP.

At this time I do not have the resources to actually do a numerical model to determine the quantitative aspects of the movement aspects of the dredged material.

(However) I did some analytical analysis of whether cyclones (and storm surges) and tsunamis can move the dredged material from Palk Bay into the channel.

The impact from cyclones and storm surges will be minimal, but tsunamis can move a significant amount of the dredged material into the channel.