2,380 CRASHES IN
IOWA, IA
2015

Of the 5 fatalities and 730 injuries recorded, motorists comprised the largest group, with 4 individuals killed and 647 injured. One pedestrian was killed and 32 were injured. While no cyclists were killed, 48 sustained injuries. These figures highlight the risks faced by all road users.

Crash patterns in Johnson County show a clear weekly and daily rhythm. Fridays were the most frequent day for crashes with 412 incidents, while the evening commute hour from 5:00 PM to 5:59 PM was the single busiest hour with 265 crashes. The majority of collisions, 1,659 out of 2,380, occurred during daylight hours.

Of the 2,380 total crashes, 1,773 (74.5%) resulted in no injuries, involving only property damage. The remaining incidents involved some level of injury, including 5 fatal crashes, 45 with serious injuries, 203 with minor injuries, and 354 with possible injuries. These 5 fatal crashes resulted in a total of 5 fatalities.

The leading contributing factor cited in crashes was 'Followed too close,' which was identified in 494 incidents (20.8%). Other significant factors included 'Driving too fast for conditions' with 196 crashes (8.2%) and collisions involving an 'Animal' with 145 crashes (6.1%). Failure to yield the right-of-way from a stop sign was also a notable factor, contributing to 125 crashes.

The majority of crashes occurred in favorable conditions. Specifically, 1,659 crashes (69.7%) happened in daylight, 1,341 (56.3%) in clear weather, and 1,614 (67.8%) on dry road surfaces. Adverse conditions were less frequent, with 225 crashes occurring during rain and 116 during snow.

Analysis of the 5,145 people involved in crashes shows that individuals in the 26-34 age group were most represented (930 people), followed by those aged 21-25 (818 people). Among the 4,375 vehicles involved, the most frequent makes were Chevrolet (651 vehicles), Ford (593 vehicles), and Toyota (533 vehicles).

The most frequently cited major cause for crashes in this dataset was 'Followed too close,' accounting for 494 incidents. 'Driving too fast for conditions' was the second leading cause with 196 crashes, followed by collisions with an 'Animal' at 145 crashes. 'Failure to yield right-of-way from a stop sign' was also a significant contributor, listed as the cause for 125 crashes.

The most common first harmful event was a 'Collision with a vehicle in traffic,' which occurred in 1,615 of the 2,380 crashes. Single-vehicle events were also common, including 135 collisions with an animal and 55 overturns or rollovers. Collisions with fixed objects like cable barriers (71), ditches (59), and curbs (29) were also frequently recorded.

Crashes were most likely to occur on non-intersection road segments, which accounted for 1,187 incidents. Four-way intersections were the most common junction type for crashes, with 575 incidents, followed by T-intersections with 207 incidents. Crashes related to driveway access were also notable, with 116 occurring near driveways.

Passenger cars were the most common vehicle type involved in crashes, accounting for 2,330 of the 4,375 vehicles. Sport utility vehicles (SUVs) were the second most common with 928 vehicles, followed by light trucks and pickups with 456. Commercial tractor-trailers were involved in 108 crashes, and motorcycles were involved in 45.

Data on traffic controls present at crash locations indicates that 2,480 of the 4,375 vehicles involved were in areas with no traffic controls present. For crashes where controls were present, traffic signals were the most common, associated with 1,291 vehicles. Stop signs were the next most frequent control device, noted for 353 vehicles.

Analysis of vehicle damage indicates that frontal impacts were the most common, with the 'Front' listed as the most damaged area for 1,200 vehicles. Rear impacts were also very frequent, with 'Rear' damage reported for 859 vehicles, which is consistent with the high number of rear-end collisions. Impacts to the driver and passenger sides were also common, indicating a significant number of angle or sideswipe collisions.

A total of 79 crashes were recorded as involving an impaired driver, representing 3.3% of all crashes. Alcohol was the most frequently cited substance, involved in 69 of these incidents. Drugs were a factor in 8 crashes, and a combination of alcohol and drugs was noted in 2 crashes.

The highest concentration of crashes within Johnson County occurred in Iowa City, which recorded 1,281 incidents. The city of Coralville saw the second-highest number with 514 crashes. Other municipalities with notable crash volumes include North Liberty with 96 crashes and Tiffin with 43 crashes.

The vast majority of crashes occurred on paved roadways, with 2,323 incidents reported on such surfaces. In contrast, 52 crashes, or approximately 2.2% of the total where surface type was recorded, took place on unpaved roads like gravel or dirt.

In a minority of crashes, specific roadway factors were identified as contributors. The most common was 'Surface condition,' such as wet or icy roads, cited in 299 incidents. 'Work Zone' conditions and 'Traffic backup from a prior crash' were each noted as a factor in 26 crashes.

While most drivers were recorded as 'apparently normal,' a number of other conditions were noted. 'Under the influence of alcohol' was the most cited non-normal condition, recorded for 79 drivers. Other reported conditions included being 'Emotional' (23 drivers) and 'Asleep/fatigued' (22 drivers).

The estimated property damage for the majority of crashes fell into the '$1,500 - $7,500' range, which applied to 1,701 incidents (71.5%). A smaller number of crashes resulted in more severe damage, with 506 estimated between $7,500 and $25,000, and 47 crashes causing damage estimated at over $25,000.

The most common type of collision was a rear-end crash, which accounted for 901 incidents, or 37.9% of the total. Single-vehicle, non-collision events like running off the road or overturning were the second most frequent type, with 585 incidents (24.6%). Broadside collisions were the third most common, occurring in 307 crashes (12.9%).

Among the 4,375 vehicles involved in crashes, the most common pre-crash action was 'Movement essentially straight,' reported for 2,238 vehicles (51.2%). Other frequent actions included 'Slowing/stopping' (475 vehicles) and being 'Stopped in traffic' (387 vehicles). Turning left was the action for 418 vehicles prior to impact.

For the 85 incidents involving non-motorists where an action was recorded, the most common circumstance was 'Entering or crossing roadway,' cited in 59 cases. A smaller number of incidents occurred while the non-motorist was moving along the roadway, either with traffic (11 cases) or on a sidewalk (3 cases).

Of the 5,145 individuals involved in crashes, the vast majority were drivers, accounting for 4,923 people (95.7%). Passengers made up the next largest group with 137 individuals. The data also includes 49 bicyclists and 33 pedestrians.

Among all 5,145 people involved in crashes, 5 sustained fatal injuries and 730 suffered non-fatal injuries. The injuries were categorized as serious for 54 people, minor for 257 people, and possible for 419 people. A small subset of 35 individuals were explicitly recorded as having no injuries.

Among the subset of 526 crash participants for whom safety equipment use was recorded, 434 were noted as using a shoulder and lap belt. However, 67 individuals in this group were recorded as using no safety equipment at all. Another 14 participants were noted as wearing a DOT-compliant helmet.

Two-vehicle collisions were the most common scenario, accounting for 1,597 of the 2,380 crashes (67.1%). Single-vehicle crashes were the next most frequent, with 599 incidents (25.2%). Crashes involving three or more vehicles were less common, with 184 such incidents recorded.