Link to QCS Corp. Home Page.
Quality Control Systems Corporation
In business since 1987 – thanks to our clients, customers, friends, and families

An Unusual Cluster of Fatal Crashes
on I-8 in San Diego County, California


Roadside boulders without guardrail.


An Unusual Cluster of Fatal Crashes on I-8 in San Diego County, California.

We have identified an unusual group of eight fatal crashes along a 33 mile stretch of Interstate 8 (I-8) in San Diego County, California. All of these crashes involved collisions with boulders that occurred as the first harmful event of the crash. These crashes extend east of the intersection of I-8 and Japatul Valley Road (California State Highway 79) to the Jacumba exit on Carrizo Gorge Road. The posted roadway speed limit where these crashes occurred was 70 miles per hour. Nine persons were killed in these crashes over a seven year period from 2002 through 2008.

All of the crashes were single vehicle crashes, not involving any pedestrians. The sequence of events is known for six of the vehicles in these crashes; of these, all began with departures from the roadway. Seven of the eight vehicles rolled over following the collision. Guardrails were not apparent in any of the street level views of these crash sites available from Google Maps on August 7, 2009.

Both the number of such crashes as well as the proportion of fatal crashes on this roadway involving first-event collisions with boulders make this cluster noteworthy. There were only twelve other similar crashes on interstate highways with 70 miles per hour speed limits in the entire United States during the period of our study.

This unusual cluster of fatal crashes was identified using data from the Fatality Analysis Reporting System (FARS) maintained by NHTSA and a statistical criterion based on the Poisson distribution that tests the likelihood of an expected number of events, given the number of events that actually occurred. This technique is related to one described in the paper: "Improving Surveillance for Injuries Associated with Potential Motor Vehicle Safety Defects." Injury Prevention, April 2004, 10:88-92, by R.A. Whitfield and Alice K. Whitfield.

If you would like further information, please to send us an email.

(Link to our Crash Mapping page.)

Link to:

QCS Corp. Home Page

Our Research

Our Press Clippings

How to Contact Us


Terms of Use and Disclaimers     Privacy

Copyright © Quality Control Systems Corp. All rights reserved.