459 CRASHES IN
IOWA, IA
2015

An analysis of killed and injured individuals shows that vehicle occupants were the most affected group, with 2 motorists killed and 202 injured. There were no pedestrian or cyclist fatalities recorded in 2015. However, 2 pedestrians and 3 cyclists sustained injuries in traffic crashes.

Crash analysis by time reveals distinct patterns, with incidents peaking on Thursdays, which saw 91 crashes. The most common time for a crash was the 3 p.m. hour, which recorded 39 incidents. The data also shows that a majority of crashes, 277 in total, occurred during daylight hours.

The majority of crashes in Sioux County in 2015 did not result in injury, with 312 property-damage-only incidents accounting for 68% of the total. The remaining 32% of crashes involved some level of injury. There were 3 fatal crashes recorded, which resulted in a total of 3 fatalities.

An analysis of contributing factors indicates that collisions involving an animal were the most common cause, cited in 65 crashes (14.2%). This was closely followed by 'Followed too close,' which was a factor in 63 incidents (13.7%). Other significant factors included 'Driving too fast for conditions' and 'Lost Control,' each contributing to 31 crashes (6.8%).

The data indicates that most crashes occurred in ideal driving conditions. A total of 277 crashes (60.3%) happened in daylight, 227 (49.5%) in clear weather, and 265 (57.7%) on dry road surfaces. Crashes in adverse conditions were less frequent, with 102 incidents occurring in cloudy weather and 44 on snowy roads.

Among the 956 people involved in crashes, the 16-20 age group was the most represented, with 178 individuals, followed by the 26-34 age group with 121 individuals. An analysis of the 743 vehicles involved shows that Chevrolet (190 vehicles), Ford (145 vehicles), and Dodge (42 vehicles) were the most frequently recorded makes.

According to the major cause data, collisions with an animal were the leading factor in crashes, accounting for 65 incidents. 'Followed too close' was the second most frequent cause, cited in 63 crashes. Other primary causes included 'Driving too fast for conditions' and 'Lost Control,' each attributed to 31 crashes, and 'Failure to yield right of way from a stop sign,' noted in 30 crashes.

The most common first harmful event was a 'Collision with a vehicle in traffic,' which occurred in 244 crashes, representing 53.2% of all incidents. Collisions with animals were the second most frequent event, with 65 cases. Single-vehicle run-off-road events were also significant, including 42 overturns or rollovers and 31 collisions with a ditch.

The data shows that more crashes occurred at non-junction locations than at intersections. A total of 252 crashes (54.9%) happened on road segments away from junctions, including 27 related to driveway access. In contrast, 154 crashes (33.5%) occurred within or related to an intersection, with four-way intersections being the most common type, accounting for 119 incidents.

Passenger cars were the most common vehicle type involved in crashes, with 288 units recorded, followed by four-tire light trucks (180) and sport utility vehicles (143). Commercial vehicles, such as tractor-trailers, were involved in 34 crashes, while motorcycles were involved in 7.

The data shows that 496 vehicles involved in crashes were in areas with 'No controls present'. Among vehicles at controlled locations, stop signs were the most frequent type, associated with 84 vehicles, followed by traffic signals, which were present for 72 vehicles.

Frontal impacts were the most common type of vehicle damage, with the front area being the most damaged point on 170 vehicles. Including corner impacts, frontal damage was noted on 290 vehicles in total. Rear-end collisions were indicated by 78 vehicles with primary damage to the rear, while side impacts were the main damage area for 72 vehicles.

The data indicates that 16 crashes, or 3.5% of the total, involved a driver under the influence. Among the 23 total instances of impairment recorded for individuals involved in crashes, alcohol was cited in 20 cases, drugs in 2 cases, and a combination of alcohol and drugs in 1 case.

Within Sioux County, crash incidents were most concentrated in Sioux Center, which recorded 95 crashes in 2015. Orange City had the second-highest number with 54 crashes, followed by Rock Valley with 24 crashes. Other municipalities with notable crash counts include Hull (18) and Hawarden (14).

The vast majority of crashes, 422 in total, occurred on paved roadways. A smaller number of incidents, 35 crashes, took place on unpaved surfaces such as gravel or dirt roads, accounting for approximately 7.7% of crashes where road surface type was specified.

In cases where a roadway factor was identified as a contributor, 'Surface condition,' such as wet or icy roads, was the most common, cited in 70 crashes. Other roadway factors were noted infrequently, with 'Shoulders' being a factor in 2 crashes and 'Work Zone' and 'Debris' each contributing to a single crash.

Among drivers for whom a condition other than 'apparently normal' was recorded, being 'Under the influence of alcohol' was the most frequent, noted for 15 drivers. Driver fatigue was also a factor, with 5 drivers recorded as 'Asleep/fatigued'. Medical conditions were cited for 3 drivers.

Officer-estimated property damage costs show that the most common range was '$1,500 - $7,500,' which applied to 288 crashes. A significant number of crashes, 144, resulted in damages between '$7,500 - $25,000'. High-damage crashes, with costs exceeding $25,000, accounted for 18 incidents, or 3.9% of the total.

The most frequent type of crash was a non-collision event involving a single vehicle, such as running off the road or an overturn, which accounted for 176 incidents (38.3%). Among multi-vehicle crashes, rear-end collisions were the most common, with 96 occurrences (20.9%), followed by broadside collisions, which happened in 86 crashes (18.7%).

An analysis of pre-crash actions for the 743 vehicles involved shows that the majority, 450 vehicles (60.6%), were moving straight ahead. The next most common action was turning left, which was the maneuver for 62 vehicles. Slowing or stopping was the recorded action for 38 vehicles prior to impact.

Of the 956 individuals involved in crashes, the vast majority were drivers, accounting for 902 people or 94.3% of the total. Passengers made up the next largest group with 48 individuals. A small number of non-motorists were also involved, including 3 bicyclists and 2 pedestrians.

Out of the 956 people involved in crashes, 3 sustained fatal injuries and 207 sustained some level of injury. This indicates that approximately 22% of all individuals involved in crashes were either killed or injured. The specific breakdown of injuries includes 19 serious, 97 minor, and 91 possible injuries.

Among the 168 vehicle occupants for whom safety equipment use was documented, 145 were recorded as using a shoulder and lap belt. A total of 19 individuals, or 11.3% of this subset, were noted as using no safety equipment at the time of the crash.

The data shows that two-vehicle collisions were the most common scenario, accounting for 251 crashes. Single-vehicle crashes were also frequent, with 192 incidents, representing 41.8% of the total. Crashes involving three or more vehicles were rare, with only 15 three-vehicle crashes and one four-vehicle crash recorded.