The effect of traffic law enforcement personnel on the motoring public was studied on U.S. Route 50 near Placerville, california by the california highway patrol. Traffic was observed during the five-year period, 1963-1967, showing a range between lowest and highest points of about 900 vehicles a day. The traffic was compared with the other main route to nevada, interstate 80, and they were quite similar in growth. This study was designed primarily to evaluate the reliability of the conclusions reported in a prior study, operation 101, oceanside. One theory retested in the study was that accidents could be reduced at specified locations by intensive enforcement actions. Another objective was to further develop the criterion for determining the amount of uniformed manpower to provide efficient service on roadways throughout california. The violation/accident relationship was also studied. Accidents were reduced 14 per cent during the study period, compared to the averaged two preceding years for operation 500, Placerville. In operation 101, oceanside, they reduced ten percent from the averaged two preceding years. There was a significant reduction in severity of accidents, those which involved some degree of injury, 17.7 per cent on the rural portion of the roadway and 11.1 on the urbanised portion. The 7 1/2 mile portion of the study route through south Lake-Tahoe accounted for approximately 50 per cent of the accidents on the entire roadway, for 11 our of 24 hours daily, during 1964-65 and for four out of every 24 hours during the study period. Single vehicle accidents during daylight hours increased from 102 to 103. However, during the hours of darkness, they decreased from 122 to 96. Exceeding safe speed was the cause of the greatest number of accidents. For Placerville, the second highest cause of accidents was from drivers unused to mountain driving. The third most voluminous cause was speed which resulted in rear end collisions. Drunk drivers who caused accidents were relatively the same proportion in both studies. As in operation 101, the 20-24 year old male drivers were larger proportions of male drivers in accidents than would be expected by the percentage that they are of licensed drivers. The majority of victims killed or injured, were passengers. The complaint of pain injury category remained stable probably because more seasoned traffic officers handled the accident investigation.
Samenvatting