Can a dam do something like this to kerala???...
The answer is YES ...
This are the after effects if the dam collapses........

If mullaperiyar dam breaks there would be heavy water flow to vandiperiyar situated 10km away along the periyar river bed. The immense power of water would destroy the vandiperiyar bridge causing huge disaster.

Water would then gush to karimkulam chappath and cause destruction to the chappath bridge which is located 26km from the dam.

Kattapana and the high range areas will get isolated and the immediate low range areas will be destroyed.

Water would then flow to upputhura causing massive destruction and then to idukki reservoir.

Idukki reservoir which is 51km from mullaperiyar dam. Idukki dam is 12km in length and consists of three dams idukki arch dam, cheruthoni dam and kulamaavu dam.

If cheruthoni there will be immense disaster in Idukki and water would flow down to boothathaankettu reservoir which is 105km from mullaperiyar.  If boothathaankettu reservoir crashes then immediate danger will be to kothamanagalam and neighbouring regions of muvatupuzha, kalady, kodanaadu e.t.c

If kulamaavu dam breaks immediate danger will be to moolamattam and water will flow down to crash the malankara dam which is 40km from kulamaavu. Areas of muttom and thodupuzha will then be affected along with the neighbouring regions of muvatupuzha, ramamangalam, piravam.

This is a small video clip showing what may happen if the mullaperiyar dam collapses .....