"If the central government headed by Modi wants to take my service and Sulabh's indigenous technologies to clean river Ganga and to set up toilets for all, I am ready to help," Pathak told reporters here.
Sulabh, an NGO, is known for its cost-effective sanitation and liberation of scavengers.
He said the focus of the central government should be sanitation for all.
"It should be the first target work of Modi's government because it is a basic need of the people and through this the problem of open defecation would end," Pathak said, adding that he would write to Modi in this connection.
He said Sulabh has 200 effluent water treatment plants across the country. "We have successfully proved that even toilet water can be treated and used for agriculture."