ORIGIN AND DESTINATION SURVEYS IN URBAN AREAS

ORIGIN AND DESTINATION SURVEYS HAVE BEEN MADE FOR MANY YEARS IN CONNECTION WITH STUDIES FOR RIVER CROSSINGS AND CITY BYPASSES AND THE TECHNIQUES FOR SUCH SURVEYS OF COMPARATIVELY LIMITED SCOPE ARE WELL DEVELOPED. GENERALLY, AUTOMOBILE DRIVERS ARE INTERVIEWD AT ROADSIDE STATIONS AND THE RESULTS CORRELATED WITH TRAFFIC COUNTS. THE FINDING THAT ALL BUT A SMALL PERCENTAGE OF THE TRAFFIC APPROACHING ANY OF THE LARGER CITIES IS DESTINED FOR THE CITY ITSELF SHOWS THAT THE GREATEST NEED IS FOR ADEQUATE HIGHWAYS LEADING INTO THE CITY RATHER THAN FOR BYPASSES. BECAUSE OF THE COMPLEXITY OF URBAN TRAFFIC, BROUGHT ABOUT BY THE INFLUENCE OF THE LARGE TRAFFIC VOLUMES, ORIGIN AND DESTINATION SURVEYS ARE ESPECIALLY NEEDED, YET DIFFICULT TO MAKE BY METHODS PREVIOUSLY USED. THE NEED FOR NEW TECHNIQUES HAS BECOME APPARENT, AND IN RECENT YEARS A NUMBER OF METHODS HAVE BEEN TRIED IN DIFFERENT CITIES. STUDY OF THIS EXPERIENCE LEADS TO THE CONCLUSION THAT THE METHOD PROMISING TO GIVE THE MOST VALUABLE INFORMATION AT THE LEAST COST IS ONE BASED ON INTERVIEWS MADE ON A REPRESENTATIVE SAMPLE OF THE DWELLING UNITS IN THE AREA, IN WHICH INFORMATION IS OBTAINED CONCERNING ALL OF THE TRAVEL FOR A DAY BY ALL RESIDENTS OF THE DWELLING UNITS, SUPPLEMENTED BY INFORMATION CONCERNING TRIPS BY NON-RESIDENTS OBTAINED AT A CORDON OF STATIONS AT THE OUTER LIMITS OF THE AREA. THE HOME-INTERVIEW METHOD IS ESPECIALLY ADAPTED TO STUDIES UNDER ABNORMAL TRAFFIC CONDITIONS, BECAUSE IT PROVIDES THE MEANS FOR ADJUSTING FOR THE ABNORMALITIES. STUDIES OF THIS TYPE ARE NOW UNDER WAY IN 24 CITIES, AND IN A NUMBER OF THESE, THE WORK HAS PROGRESSED TO THE ANALYSIS STAGE. FIRST RESULTS ARE CONFIRMING THE VALUE AND THE PRACTICABILITY OF THE METHOD. /AUTHOR/