(A) To provide for consistency during analysis, common peak hours were selected at all studied locations during the AM and PM periods. The peak hours chosen were from 7:40 to 8:40 a.m. and from 4:35 to 5:35 p.m.
(B) For the purposes of transportation facility analysis and design, the 30th highest annual hour (30 HV) of traffic volume is typically the time period of interest. The 30 HV is also used by ODOT as the basis for highway mobility standards. Therefore, all volume data collected was adjusted to better reflect this time period.
(C) (1) Because there are no local or comparative sources of traffic volume data that indicate how volumes fluctuate throughout the year, ODOT’s 2008 Seasonal Trend Table was used to determine how the collected counts should be factored to replicate the 30 HV.
(2) The Seasonal Trend Table was developed by ODOT by averaging seasonal trends at Automatic Traffic Recorder (ATR) stations throughout the state that continuously collect traffic volume data.
(3) For traffic characteristics through Joseph, the seasonal trends from ATRs on routes described as “recreational summer” were used.
(D) For “recreational summer” routes, the 30 HV typically occurs in mid-July. Because the traffic counts in the city were collected on 7-23-2008, the count data obtained was taken to be representative of the 30 HV and no seasonal factoring was applied. It should be noted that the Chief Joseph Days festival/rodeo had begun on the day the counts were collected and that as a result, the traffic volumes may actually be higher than the 30 HV. However, after comparing the volumes to historical counts and conducting a sensitivity test on the operational analysis, it was determined that while the counts may be conservatively high, they would not be high enough to affect the study findings (Confirmed with Dorothy Upton, ODOT Transportation Planning Analysis Unit (7-29-2008)).
(E) The resulting 30 HV traffic volumes at the three study intersections are displayed in the “Existing and Future AM/PM Peak Hour Traffic Volumes” map (showing both 2008 volumes as well as forecasted 2030 volumes). Volumes of bicycles by intersection approach and pedestrians by crosswalk for each of the three intersections during the 2008 AM and PM peak hours are displayed in the following figure. When examining the volumes of motor vehicle, bicycle and pedestrian traffic at each of the three intersections, the intersections along Oregon 82 are shown to experience far more traffic than the intersection on Imnaha Highway at College Street, where volumes are relatively low. Also, traffic volumes are higher in the afternoon than in the morning. Finally, as expected given the surrounding land uses, the pedestrian activity along Oregon 82 is fairly high.
(F) In addition to the motor vehicle turning movements and bicycle and pedestrian volumes, daily traffic volumes on area streets were obtained and displayed in the “Weekday 24-hour Two-Way Traffic Volumes (2008)” map. To provide a frame of reference when viewing the daily traffic volumes, roadways maintaining average daily traffic volumes of less than 3,000 vehicles are generally considered acceptable for shared use of travel lanes between motor vehicles and bicycles, while roadways with daily volumes of less than 1,500 vehicles are often considered desirable for residential neighborhood streets (assuming posted speeds are compatible with these uses). As shown in the “Weekday 24-hour Two-Way Traffic Volumes (2008)” map, all streets within the city, with the exception of Oregon 82, Imnaha Highway and Wallowa Avenue, are maintaining traffic volumes well below these thresholds, with shared bicycle-motor vehicle use of travel lanes possible on some segments of these roadways as well.
(G) At several of the locations where 24-hour volume data was collected, additional information showing hourly motor vehicle volumes by direction of travel was obtained as well. The hourly volume profiles for these locations are provided in the following figures, showing how traffic volumes change during each hour of the day.
(H) When examining the volume profiles, it is shown again that the traffic volumes on streets within the city, with the exception of Oregon 82, Imnaha Highway and Wallowa Avenue, are low. In fact, traffic volumes on most streets are so low that residents are comfortable walking on them without the presence of sidewalks.
(I) Also, in most cases, traffic is nearly non-existent between midnight and 5:00 a.m. It is also common to experience a more gradual rise and distribution of traffic throughout the day, rather than having dramatic morning and afternoon rush hour periods as are often experienced in larger urban areas.
(J) It should also be noted when viewing the hourly volumes from locations surrounding the rodeo grounds (e.g., Oregon 82 north of Maple Street, Alder Street west of Mill Street, Wallowa Avenue west of Oregon 82 and McCully Avenue west of Mill Street) that rodeo-related traffic caused the notable traffic peaks during the evening hours.
(Ord. passed 6- -2009)