Here is an article from rediff.com, that explains the safty plans in MAPS design that helped it withstand Tsunami.
In these difficult hours in South Asia after the deadly tsunami, there is something to be proud of for India.
It's time to acknowledge the achievement of Indian scientists who designed and built the Kalpakkam nuclear power reactors without foreign assistance. The nuclear station withstood the devastation of the Big Wave because it is not even imaginable what would have happened had the tsunami damaged the two nuclear power units situated on the shore.
L V Krishnan, former director, safety research and health physics at the Indira Gandhi Centre for Atomic Research at Kalpakkam, explains how the great disaster was forestalled because of scientific planning.