This article concerns the use in The Netherlands of hard shoulder running to ease motorway or trunk road congestion, which is to be tested in the UK. Hard shoulder running helps to relieve motorway congestion when a conventional lane has become blocked by an accident or breakdown. Initial safety concerns were dispelled by the discovery that fewer accidents took place as drivers were not running in congested traffic and making risky or careless manoeuvres. The first trials went well and the scheme was expanded. Safety havens are built in to the hard shoulder with sensors connected to the central control room. If it is necessary to move emergency vehicles to an accident, hard shoulder use can be switched off. Hard shoulder running is activated automatically by embedded in-road sensors and access controlled by variable message signs. In addition, the Dutch are testing the use of an extra, narrow-width outer lane for congested times: this will be used as an alternative to hard shoulder running.
Abstract