New Delhi, May 3 -- The Delhi Urban Shelter Improvement Board (Dusib) has started work on upgrading basic civic infrastructure in "katras" located in Chandni Chowk, beginning with a pilot covering five "katras" in the Ballimaran area, officials said. A "katra" is a gated cluster of residential and commercial units, designed as small, self-contained courtyards. The move comes as part of a broader effort to address longstanding issues related to sanitation, drainage, structural safety and access in the densely built neighbourhoods of Shahjahanabad, where residential clusters are organised into "kuchas" (lanes) and "katras" (enclosed housing blocks). Officials said the project will focus on improving essential services such as sewer lines, water supply networks, paving of internal pathways, street lighting and waste management systems. "The idea is to take up a cluster-based redevelopment of katras, starting with five in Ballimaran, and then scale up across the Chandni Chowk area," a senior DUSIB official said....