Injuries from Crashes

How many people are injured on Bay Area roads?

Injuries from Crashes

Definition: 
Injuries from crashes refers to serious but not fatal injuries sustained in a collision. The California Highway Patrol classifies a serious injury as any combination of the following: broken bones; dislocated or distorted limbs; severe lacerations; skull, spinal, chest or abdominal injuries that go beyond visible injuries; unconsciousness at or when taken from the scene; or severe burns. Injuries are measured as an aggregate number (total injuries) and as a rate (injuries per 100,000 residents and injuries per 100 million vehicle miles traveled).

When millions of people drive billions of miles each year, the unfortunate reality is that crashes resulting in death or serious injury continue to occur. Fatalities understandably tend to receive the most attention, but serious injuries from crashes affect five times as many people each year. Several factors influence the number of injuries from crashes, including driver education and behavior, vehicle safety features, roadway conditions, and the number of miles driven.

Regional Performance
More people were injured on Bay Area roadways in 2016 than in any year since 2001.

In 2016, nearly six people were seriously injured in a crash every single day in the Bay Area – an indication that more work remains to be done to make sure motorists, pedestrians and bicyclists can all get to their destinations safely. Over the past decade, although motorists continue to account for the majority of serious traffic injuries, the annual number of non-motorized injuries increased 28 percent. The top 3 primary collision factors for crashes that resulted in injuries are unsafe speed, improper turning, and driving under the influence.

Local Focus
The rate of injuries resulting from collisions varies greatly by county.

Nearly 40 percent of the region’s serious injuries occur in Alameda and Santa Clara counties, which is perhaps not surprising given these counties’ large populations and high vehicle-mileage traveled. However, in urban San Francisco – where bicyclists and pedestrians accounted for over half of the serious injuries – the per-VMT injury rate was highest in the region. The North Bay counties of Napa and Sonoma also have above-average injuries per-VMT due to more miles of rural roads, which have higher crash rates.

Sources: 

California Highway Patrol: Statewide Integrated Traffic Records System (2001-2016) – via SafeTREC Transportation Injury Mapping System

California Department of Transportation: California Public Road Data/Highway Performance Monitoring System (2001-2016)

California Department of Finance: Population and Housing Estimates

Form E-8 - Historical Population and Housing Estimates (2001-2010)

Form E-5 - Population and Housing Estimates (2011-2016)

Image: Flickr (Creative Commons license), Photographer: Chris Humphrey, https://www.flickr.com/photos/studioh/52013097

Methodology Notes: 

The data is reported by the California Highway Patrol (CHP) to the Statewide Integrated Traffic Records System (SWITRS), which was accessed via SafeTREC’s Transportation Injury Mapping System (TIMS). The data was tabulated using provided categories specifying injury level, individuals involved, causes of collision, and location/jurisdiction of collision (for more:  http://tims.berkeley.edu/help/files/switrs_codebook.doc) . Injuries were normalized over historic population data from the US Census and American Community Surveys and vehicle miles traveled (VMT) data from the Federal Highway Administration.

The crash data only include crashes that involved a motor vehicle. Bicyclist and pedestrian injuries that did not involve a motor vehicle, such as a bicyclist and pedestrian collision or a bicycle crash due to a pothole, are not included in the data.

For more regarding reporting procedures and injury classification, refer to the California Highway Patrol Manual (http://www.nhtsa.gov/nhtsa/stateCatalog/states/ca/docs/CA_CHP555_Manual_...).