Udayamurthy, 85, is survived by two sons and a daughter.
Author of several books on self-improvement, Udayamurthy's prominent works include "Ennangal" (thoughts) "Unnal Mudiyum Thambi" (You can brother), "nee than thambi mudhal amaichar" (you are the chief minister).
An environmental activist, Udayamurthy, founder of "Makkal Sakthi Iyakkam" (People's Power Movement), actively pursued projects like linking of rivers.