GIS-GPS Integration for Information & Surveillance of Urban Expressways in Indian Context Saurabh Gupta Transport Planner Halcrow Consulting India Ltd., India Email: GuptaS@halcrow.com Dr. Tom V. Mathew Asst. Professor Indian Institute of Technology Bombay Email: vmtom@iitb.ac.in Traffic congestion is the most visible manifestation of the failures in urban traffic operations. It is a well-documented fact that relief from developing more expressways in our metropolitan cities has only been temporary for traffic management. Besides, considerable amount of traffic congestion is caused not by the sheer volume of traffic, but by poor information about optimal routing. Some of this is due to ignorance of where and when congestion is occurring and hence the inability to provide information to others in the traffic stream. The more efficient use of the existing road network is the application of Intelligent Transportation System (ITS), an integration of GIS, GPS and dynamic information systems like Variable Message Signs (VMS’s). However, the fact that Indian traffic conditions are mixed in nature, these technologies supporting algorithms for computation of macro & microscopic traffic parameter need to be explored/ developed accordingly. Keeping this in view, this paper investigates the technique of estimating the link travel time by using the model given by Coifman (2003) from video-recorded field data. To illustrate this, a case study was undertaken considering a small stretch on the western expressway in Mumbai and comparative assessment of estimated travel time was carried out by using the GPS receiver. Shockwave (uc), a constant in the algorithm was calibrated by simulating the same stretch in VISSIM (microscopic traffic simulation package). On application front, a large network with VMS’s can be integrated with the Geographical Information System (GIS) to empower the commuters to act and decide which corridor to follow leading to less congestion.