The most recent five years (2003 to 2007) of crash data for all roadways within the city urban growth boundary (UGB) was obtained from the ODOT Crash Analysis and Reporting Unit and analyzed to identify high crash locations and crash patterns where countermeasures may be needed to improve safety, specially in regards to walking and biking. Crashes reported over that period of time have been illustrated in the “2003-2007 Reported Crashes” map, which has been organized to show all crash locations and types of crashes that occurred.
(A) Crash characteristics.
(1) From the “2003-2007 Reported Crashes” map, it is seen that crashes within the city have been spread out, with no noticeable concentration of crashes occurring at any one location. Also, nearly half of all of the crashes occurred along Oregon 82, which should be expected given the higher traffic volumes.
(2) Of the 19 total crashes that occurred over the five-year period, the types of crashes are varied. The figure below compares the number of crashes per crash type experienced . As shown, crashes involving backing maneuvers and sideswipes were the most common, but the numbers of those crash types were not significantly higher than most others.
(3) It should also be noted that there was one crash that involved a pedestrian crossing Oregon 82 south of Sixth Street. According to the crash record, the pedestrian was crossing the highway at a mid-block location at night. There were no reported crashes involving bicycles.
(4) In general, the severity of crashes experienced was low, with 13 of the 19 total crashes resulting in only property damage with no injuries. Five crashes resulted in possible or minor injuries (reported as “Type C Injuries”), while only one crash resulted in moderate injures (reported as “Type B Injuries”). There were no crashes resulting in incapacitating or fatal injuries reported and only two of the six total crashes resulting in injuries were found to have occurred on the highways.
(5) In searching for other potential crash trends, it was found that most crashes occurred under daylight conditions (79%), with dry pavement (74%), and were spread out relatively evenly among all days of the week. Crashes were also spread out relatively evenly among the months of the year, with slight peaks in the months of July and November. There was also a slight trend towards crashes occurring during the mid-day hours.
(B) Crash rates.
(1) To help assess whether the number of crashes experienced on the state highways through the city is significant, crash rates per million vehicles miles (MVM) on Oregon 82 and Imnaha Highway were compared to those experienced on similar facilities throughout the state. The use of crash rates as a means of comparison between facilities is common practice because it accounts for the differences in traffic volumes served, which is typically proportional to the number of crashes.
(2) Crash rates for study area highways were taken from an annual publication by the ODOT Crash Analysis Reporting Unit called the State Highway Crash Rate Tables (2006 State Highway Crash Rate Tables, ODOT Transportation Data Section, Crash Analysis & Reporting Unit, July 2007). In this document, crash rates for given segments of all state highways are calculated and listed for each of the last five years. In addition, this document provides average crash rates over each of the last five years for various types of facilities, separating urban and rural environments and freeways from non-freeways, to allow for comparison between similar facilities. When comparing highway segments from the study area to the statewide averages for similar facilities, the use of segments less than one mile in length was avoided, as crash rates for such short segments can be heavily influenced by a single problem location.
(3) When examining the crash data over the last five-year period (note that due to the publishing date of the Crash Rate Tables, the five-year span from 2002 to 2006 was the most recent available), it was noticed that there had not been any reported crashes on the V4-mile segment of Imnaha Highway within the city limits from 2003 through 2006. However, in 2002, there were three reported crashes, which is a significantly high amount for such a short segment of roadway. Because no crashes have been found to occur since then (even in 2007, as evidenced by the new crash data obtained), a comparison of the crash rates for this segment of highway to the statewide average rates would not be of value as there is clearly no trend of frequent crashes occurring on a consistent basis.
(4) In the Crash Rate Tables, Oregon 82 is comprised of two separate state highways: Highway 10, which approaches from the north and ends at the Imnaha Highway intersection, and Highway 351, which begins at the Imnaha Highway intersection and runs past the end of Wallowa Lake. For the purpose of this analysis, the segments of each separate highway along Oregon 82 within the city limits were combined into one 1.24-mile long segment. The resulting crash rates during each of the five years examined are shown in the following table, with the statewide average crash rate for principal arterials in rural cities also provided for comparison. As shown, the crash rate for this segment was significantly lower than the statewide average rate during most years, with the exception of the year 2002. Further examination of crash data revealed that three crashes occurred within the segment of Oregon 82 from the north city limits to the Imnaha Highway intersection during the year 2002, which is relatively high for such a short distance. However, since crash rates have substantially dropped every year since then, the rate of crashes occurring on Oregon 82 within the city limits is not of concern.
Table 1-OR82 5-year Crash Rate Comparison for Statewide Rural Cities (2002-2006) | ||||||||
Section Limits (mile points) | Section Description | Annual Crashes per Million Vehicles | ||||||
Statewide average rate | 1.16 | 1.28 | 0.99 | 0.90 | 0.94 | |||
Hwy 10 MP 70.98 - Hwy 351 MP 0.80 | OR 82 from north city limits to south city limits | 2.19 | 1.10 | 0.57 | 0.00 | 0.60 | ||
NOTES TO TABLE: Bold type indicates the crash rate is greater than the statewide average. | ||||||||
(Ord. passed 6- -2009)