Dr. Tyagi provided technical and policy support for large scale implementation of land rehabilitation programmes. The potential of technology was demonstrated through large-scale pilot projects in different parts of the country. Though technology dissemination programmes were set in a network mode spread across the states, the major programmes were implemented in Ghaggar-Yamuna Basin in Haryana and Rajasthan, Upper Ganga Basin in Uttar Pradesh and North-West Gujarat. As member of the Bureau of Indian Standards, he has been responsible for developing code of practice for water application methods, sub surface drainage. As Member of  the apex technical advisory committee on Sodic Land Reclamation Project executed in Uttar Pradesh  with World Bank assistance, he provided much needed guidance to the project resulting in rehabilitation of 190,000  ha sodic land. He was one of the few individuals who advocated government support for advanced water management technology in place of consumables like electricity and water.

Sustained efforts led to development of master plans for rehabilitation of land and identification of institutions for undertaking such works in governmental and nongovernmental organizations.