A Little More Traffic Causes Lots More Accidents

Even a modest increase in traffic was outpaced by the frequency and severity of accidents, most of which happened in broad daylight.


Traffic volume on the Key Peninsula has increased at a relatively low rate in recent years despite appearances and a steeper rise in car accidents. 

The Key Peninsula News analyzed data from the Washington State Department of Transportation, the Pierce County Department of Planning and Public Works, the Washington State Patrol, the KP Fire District, and the Pierce County Sheriff’s Department to evaluate accidents and traffic on the KP. 

An average of 22,000 cars crossed the Purdy Bridge each day in 2019. That dropped to 19,000 during the pandemic, but was back up to 21,000 in 2022. There were 17,000 counted on State Route 302 at the junction with the KP Highway. Of those vehicles, 8,000 continued west on SR-302 and 9,000 traveled south on KP Highway. The average daily count in Key Center was 7,910. 

Vijay Kulkarni, associate traffic engineer with Pierce County Planning and Public Works, told KP News that Key Center is one of a handful of permanent count stations in the community. He said the KP Highway is classified as a major arterial and that similar roads in the county typically have double that volume or higher. 

Despite appearances, Kulkarni said the increase in vehicles traveling through Key Center over the last 30 years was just 12%. 

The average daily number of vehicles in Purdy increased from 18,000 in 1993 to 22,000 in 2019, a 22% increase at the Purdy Bridge and an 18% increase on the KP Highway at SR-302. 

The population of the Key Peninsula grew approximately 40% from 11,016 in 1990 to 18,318 in 2020, according to the U.S. Census Bureau. The population increased by just 1,352 between 2010 and 2020, or approximately 7%.

There were between 240 and 277 accidents each year between 2017 and 2021 on the KP, according to the Pierce County Sheriff’s Department. That rate is comparable to the county accident per capita average. 

However, the percentage of fatal accidents on the KP compared to the rest of the county is more than double what might be anticipated. Over the last five years it has ranged from a low of one fatality out of 57 in 2018, representing 2% of all traffic fatalities in Pierce County, to a high of four out of 66 in 2019, or 6% of the county total.  

About 6% of all accidents reported in Pierce County involved drugs or alcohol over the last five years but were present in 24% to 36% of fatal incidents countywide. The rate was slightly higher for the KP at 40%, where five of the 12 vehicular fatalities in the last five years involved driver impairment.

In 2021, the KP fire district responded to 106 total traffic accidents. By the middle of August 2022, it had responded to 76.

Two-thirds of all traffic accidents on the KP in the last five years occurred on SR-302 or the KP Highway, according to Washington State Patrol data. Nearly two-thirds of those accidents took place during clear weather, and three-quarters took place during daylight hours.

Update: The number of Pierce County traffic fatalities has been corrected since the print edition.