5,159 CRASHES IN
IOWA, IA
OCTOBER 2015

Motorists constituted the largest group of casualties, with 19 individuals killed and 1,679 injured. Among vulnerable road users, four pedestrians were killed and 61 were injured. No cyclists were killed, but 38 sustained injuries during this period.

Crash frequency peaked on Friday with 1,071 incidents, making it the most common day for collisions. The afternoon commute hour of 3 p.m. was the single busiest hour, with 402 crashes recorded. Overall, crashes were most prevalent during daytime hours, with 2,965 incidents occurring in daylight conditions.

The majority of crashes, 3,702 incidents or 71.8%, resulted in no injuries. However, 1,434 crashes involved at least one injury, categorized as possible, minor, or serious. There were 23 distinct fatal crashes during this period, which resulted in a total of 24 fatalities, as a single crash can involve more than one death.

Severity is per crash event (most severe injury). 23 fatal crash events resulted in 24 persons killed.

The most significant contributing factor identified in crash reports was the presence of an animal, which was cited in 1,029 incidents (19.9%). Following this, tailgating was a major issue, with 'Followed too close' listed as the cause in 528 crashes (10.2%). Failure to yield the right-of-way from a stop sign was the third-leading factor, contributing to 293 crashes.

The vast majority of collisions occurred in ideal driving conditions. Specifically, 3,094 crashes (59.9%) happened in clear weather and 3,681 (71.4%) on dry road surfaces. Crashes during daylight hours accounted for 2,965 incidents (57.5%), indicating that most collisions were not related to adverse environmental factors.

Among persons involved in crashes, the 26-34 age group was the most represented, with 1,703 individuals. Analysis of the 8,714 vehicles involved shows that Chevrolet (1,748 vehicles), Ford (1,397 vehicles), and Toyota (655 vehicles) were the most frequent makes recorded in crash reports. These figures represent the vehicles involved, not a reflection of market share.

The leading major cause of crashes was attributed to animals, accounting for 1,029 incidents. The second most common cause was 'Followed too close,' cited in 528 crashes. 'Failure to yield right-of-way from a stop sign' was the third-leading cause, contributing to 293 collisions.

The most common first harmful event was a collision with another vehicle in traffic, which occurred in 2,852 crashes. The second most frequent event was a collision with an animal, recorded in 1,007 incidents. Collisions with fixed objects, such as ditches (169) and utility poles (76), were also notable.

Crashes were most likely to occur on non-junction road segments, which accounted for 2,200 incidents. Intersections were the location for 1,750 crashes, with traditional four-way intersections being the most common type, hosting 1,284 of these collisions. Driveway-related incidents were also a factor, with 192 crashes occurring near a driveway access point.

Passenger cars were the most common vehicle type involved in crashes, with 4,281 units, followed by sport utility vehicles (1,744) and four-tire light trucks or pickups (1,364). Tractor-trailers were involved in 238 incidents, while motorcycles were involved in 78 crashes. These vehicle types represent a combined total of 8,714 vehicles involved in collisions.

A significant number of crashes occurred in areas with no traffic controls present, with 4,731 such instances noted in vehicle reports. Locations with traffic signals were the site of the next highest number of incidents, with 1,906 vehicle involvements recorded. Crashes at intersections controlled by stop signs were also common, with 935 vehicle involvements noted.

Frontal impacts were the most frequent type of vehicle damage, recorded on 2,270 vehicles. Rear impacts, often associated with rear-end collisions, were the second most common, affecting 1,141 vehicles. Damage to the front corners of vehicles was also prevalent, with 694 impacts to the passenger side and 624 to the driver side.

A total of 134 crashes, or 2.6% of all incidents, involved a driver suspected of being impaired. Alcohol was the most frequently cited substance, involved in 124 of these crashes. Drug impairment was suspected in 6 crashes, while a combination of alcohol and drugs was noted in 4 incidents.

Crash distribution was most concentrated in Iowa's most populous counties. Polk County recorded the highest number of incidents with 931 crashes, representing 18.0% of the statewide total. Scott County followed with 384 crashes, and Linn County had 310 crashes.

Among incorporated areas, Des Moines experienced the highest crash volume with 522 incidents. Davenport recorded the second-highest number of crashes at 296, followed by Cedar Rapids with 192. These figures do not include crashes that occurred in unincorporated areas of their respective counties.

The vast majority of crashes, 4,894 incidents, occurred on paved roadways. However, Iowa's extensive secondary road network was also a factor, with 253 crashes, or approximately 4.9% of the total, taking place on unpaved surfaces such as gravel or dirt.

Roadway-related factors were cited as a contributor in a minority of crashes. The most common issue was the road surface condition, such as being wet or icy, which was noted in 132 incidents. Work zones were a contributing factor in 53 crashes, while debris on the roadway contributed to 16 crashes.

Among drivers where a condition other than 'apparently normal' was recorded, impairment due to alcohol was the most common, noted for 155 drivers. Fatigue or falling asleep was the second-leading condition, affecting 83 drivers. An emotional state, such as anger or depression, was noted for 43 drivers involved in crashes.

The distribution of crashes across Iowa's six DOT districts shows the highest concentration in District 1, which includes the Des Moines metro area, with 1,505 crashes. District 6, covering eastern Iowa including Cedar Rapids and Davenport, had the second-highest volume with 1,399 crashes. Together, these two districts accounted for over half of all crashes in the state.

The most common estimated cost of property damage was in the $1,500 to $7,500 range, which applied to 3,759 crashes. A smaller but significant number of incidents resulted in severe damage, with 103 crashes estimated to have costs exceeding $25,000. Only 168 crashes were estimated to have damage under $1,500.

Single-vehicle crashes, categorized as non-collisions, were the most frequent type of incident, accounting for 1,863 crashes or 36.1% of the total. Among multi-vehicle incidents, rear-end collisions were the most common, with 1,231 crashes (23.9%). Broadside collisions were the third most frequent manner of collision, occurring in 824 incidents (16.0%).

For the 8,714 vehicles involved in crashes, the most common action immediately prior to the incident was moving straight ahead, which was the case for 4,989 vehicles. Turning left was the second most frequent pre-crash action, recorded for 835 vehicles. Slowing or stopping in traffic was the third most common action, noted for 485 vehicles.

For the 103 non-motorists involved in crashes, the most frequently recorded action was entering or crossing a roadway, which was documented in 79 cases. A smaller number of incidents involved non-motorists moving along the roadway with traffic (10 cases) or on a sidewalk (5 cases).

Of the 10,646 individuals involved in crashes, the vast majority were drivers, accounting for 10,130 people (95.2%). The remaining individuals included 406 passengers, 65 pedestrians, and 38 bicyclists. A small number of other non-motorists were also involved.

Among all 10,646 people involved in crashes, 24 sustained fatal injuries and 1,783 suffered some level of injury. The most frequently reported injury level was 'Possible,' with 1,064 individuals, followed by 'Minor' injuries for 571 people. A total of 148 individuals sustained serious injuries.

Based on available data for vehicle occupants, 1,153 individuals were recorded as using a shoulder and lap belt at the time of the crash. In contrast, 143 occupants were noted as not using any safety equipment. This information was not recorded for all participants.

Two-vehicle collisions were the most common scenario, accounting for 2,938 incidents, or 56.9% of all crashes. Single-vehicle crashes were the second most frequent type, with 1,936 incidents (37.5%). Crashes involving three or more vehicles were less common, with 245 three-vehicle pileups recorded.