Delhi Spatial Data Infrastructure portal that provides detailed information on the capital’s overground and underground utilities has been launched on 27 November 2009.The underground utilities comprising water, sewer, telephones, power lines etc have been mapped for the first time using state-of –the- art technology. The availability of underground utilities in digital form would enable the concerned line departments to undertake preventive maintenance programmes as well as locate the fault in the underground utility with precisionaccording to Delhi Chief Minister Ms. Dikshit said.The common data base will be made available to various government departments for design, planning, execution and monitoring of all infrastructure projects. This would help improve efficiency and productivity of all city services by reducing conflict of interest and cost of duplication of work.For the first time in India an entire city had been mapped on a large scale (1:2000) using aerial photography to produce an accurate base map, capture and overlay all overground and underground utilities, create a 3-D city model and undertake property survey of all dwelling units.

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