Nirbhai Singh, an undertrial, wrote a letter from Ludhiana’s Central Jail five years ago and stirred industry and government into action. Addressed to the High Court of Punjab and Haryana, the letter expressed concern over pollution in the city. The court then began to look into the state of environment, in particular the Buddha Nallah. The government took up the matter in earnest and as a result, Ludhiana now has a Rs 650 crore remedial action plan. It aims to treat all its wastewater by March 2012.