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Planning and operations require good information, but the information need not be continuous.  Continuous, real time information is needed only where operation of ramp meters or signs are being changed based on traffic conditions rather than on time of day.  Real-time information is also useful for travelers if there are locations where congestion varies from day to day.

To develop a better information system, first identify congested locations.  Then make an inventory of existing traffic surveillance facilities and confirm that they are providing accurate and reliable information.  If they are not, repair all that would be useful for operations or planning.  Set up a system for monitoring their accuracy and reliability.

Consider installing permanent surveillance devices with communication links to the traffic management center at congested locations where:

• congestion could be reduced by varying the signal timing in response to within-day or and day-to-day variations in traffic
• traffic conditions are rapidly changing due to new jobs, housing, or other activity
• incidents are likely
  
  

At other congested locations use portable traffic surveillance devices to periodically measure volumes and occupancy over the congested periods in each location.  Use floating cars to measure travel time over the congested period to determine delay.

Archive the information in manner that makes it easy to manipulate and retrieve.