Visionary Thinking: Traffic Management's New Screen Star

A new type of signage for situations where traffic must be halted on an emergency basis is discussed in this article. It uses "water screen technology," and it is being deployed in the Sydney Harbor Tunnel. Opened to traffic in 1992, it now averages about 86,000 vehicles a day. It is 2.3 km long and alleviates congestion on the Sydney Harbor Bridge. The tunnel is a key access route for the city's business district and eastern suburbs. It has experienced some 10,500 incidents ranging in severity since it opened. Delays have also been caused by drivers of over-height trucks entering the tube. The water screen is unlike any other signage because it appears directly in front of the driver's vision, making it impossible to miss or ignore. Once vehicles have stopped, a physical barrier is deployed. It has been tested on over-height trucks using a multi-step warning system to avoid sudden stops. The screen becomes fully operational in less than three seconds. Those who are not over-height can pass through in an emergency. It has been successfully used in 23 situations in daylight and night-time. There has been no damage to cars or the tunnel as a result.


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Filing Info

  • Accession Number: 01114111
  • Record Type: Publication
  • Source Agency: UC Berkeley Transportation Library
  • Files: BTRIS, TRIS
  • Created Date: May 22 2008 3:27PM