JODHPUR, Oct. 30 -- Rajasthan has begun a phased exercise to scientifically map the floodplains of Chambal and Banas rivers, identify areas vulnerable to flooding and regulate development along their banks, according to a report recently filed by the state government before the National Green Tribunal (NGT). The exercise is intended to help preserve the natural flow of rivers and reduce flood-related risks. The state's Water Resources Planning Department has set out a tentative schedule of milestones extending from August 15, 2026, to December 31, 2029, for floodplain zoning of the Chambal river. The project is being pursued in line with the Central Water Commission's technical guidelines issued in July 2025. The report forms part of proceedings before the NGT in a case concerning alleged illegal construction and encroachments along the floodplains and riverbanks of 13 major river systems, including the Ganga and Indus. Rajasthan's response outlines the measures being undertaken to protect the Chambal and Banas rivers, which form part of the Ganga river basin. According to report, a key part of the plan is to establish where river channels and flood-prone areas lie before marking their boundaries on the ground. Once scientific mapping is complete, the state says it will install boundary pillars and undertake plantation along identified stretches, with district-level committees overseeing the work. The department initially directed officials in April to map the Banas from its origin to its confluence with the Chambal. In June, the scope was extended to cover the Chambal from the point where it enters Rajasthan to where it leaves the state, as well as the Banas along its course. A dedicated committee was constituted on June 24 to approve the assignment's terms of reference and coordinate implementation across departments. In a communication to the National Mission for Clean Ganga on July 9, the department said the exercise for both rivers was under active implementation, with the terms of reference in the final stages of approval. It also said financial assistance had been sought from the Centre and that the project was expected to take 18 to 24 months from the award of the assignment.Alongside the river-mapping exercise, Rajasthan has district-level committees headed by district collectors to identify and remove encroachments from river channels and other water bodies. These committees include officials from the police, forest, public works, revenue, mining and water resources departments, among others. The state told the tribunal that 845 cases involving tenancy rights granted over river land in violation of Section 16 of the Rajasthan Tenancy Act, 1955, had been cancelled in Sawai Madhopur district. In Dausa, the district collector has directed tehsildars to submit monthly reports on cases registered under Section 91 of the Rajasthan Land Revenue Act and take action against identified encroachments....