THREE SCHEMES FOR IMPROVED LINE-HAUL BUS RAPID TRANSIT

THE SINGLE MOST IMPORTANT ELEMENT IN ATTRACTING TRANSIT RIDERSHIP IS PROVISION OF A DEPENDABLE AND COMPETITIVE PORTAL-TO-PORTAL TRAVEL TIME. THIS CAN BE ASSURED ONLY IF, IN THIS CASE, BUS OPERATION CAN ACHIEVE A HIGHER AVERAGE LINEHAUL SPEED THAN THAT OF AUTOS MOVING IN THE SAME CORRIDOR. AS A COROLLARY, BUS TRAFFIC SHOULD HAVE A REASONABLE IMMUNITY TO GENERAL CONGESTION AND INCIDENT-INDUCED STOPPAGE. THE TECHNOLOGY AND OPERATIONAL CHARACTERISTICS OF THREE SYSTEMS DESIGNED TO ACHIEVE COMPETITIVE STATUS ARE REVIEWED. THE BUS--FREEWAY SYSTEM EMPLOYS FREEWAY SURVEILLANCE AND RAMP METERING TOGETHER WITH PREFERENTIAL ACCESS. THE RESERVED LANE CONCEPT HAS BEEN MADE MORE PALATABLE TO MANY BY THE SUGGESTION THAT THE LONG HEADWAYS BETWEEN BUSES BE FILLED WITH CAR POOLS. WHEREAS THE BUS--FREEWAY SYSTEM DEPENDS MAINLY ON THE MOTORIST'S EXPERIENCE IN THE PRIORITY- MERGE SITUATION AS AN INDUCEMENT TO MODAL SHIFT, THE RESERVED LANE CONCEPT DEPENDS ON A SPEED DIFFERENTIAL BETWEEN LANES ON THE FREEWAY ITSELF. THE THIRD SYSTEM IS A PROPOSAL FOR CONSTRUCTION OF SEPARATE ROADWAYS THAT WOULD BE FOR THE EXCLUSIVE USE OF BUSES, AT LEAST DURING PEAK PERIODS. THE THREE SYSTEMS ARE COMPARED WITH RESPECT TO MOVEMENT CAPABILITIES, MOVEMENT COSTS, COST EFFECTIVENESS, ACCIDENT POTENTIAL, AND IMPLEMENTATION PROBLEMS. IT IS CONCLUDED THAT THE EXCLUSIVE BUSWAY IS THE MOST COST EFFECTIVE SYSTEM AND ALSO THE SAFEST.