Transportation officials consider ways to stem worsening I-90 congestion

Regular drivers on Interstate 90 during rush hour don’t need to be told the obvious: Congestion is getting worse.

A new state report confirms what has become common knowledge. Backups and slowdowns are routine in the morning and evening. The length of freeway affected by slowdowns has expanded from a half-mile in 2013 to 3.8 miles in 2015.

In 2015, the eastbound I-90 evening commute saw nearly 4 miles of congestion lasting about an hour from the downtown viaduct to the widened segment just east of Havana Street, the congestion report said.

“This is a significant increase in routine congestion over 2013 in terms of both length (3.3 miles longer) and duration (35 minutes longer). The morning routine congestion on westbound I-90 expanded by a mile, while the duration increased by 10 minutes from 2013 to 2015,” the report said.

Average daily traffic at the Sprague Avenue interchange increased by 5 percent, from 112,000 vehicles in 2013 to 118,000 in 2015.

Time lost in traffic tie-ups on I-90 doubled from 2013 through 2015, according to the study released in November. The state found 80,000 hours were lost to people caught in rush-hour congestion on I-90 compared with 40,000 hours in 2013.

The I-90 corridor carried an estimated 235.3 million people in individual trips in 2015, an increase of 1.9 percent over 2013.

“Also contributing to delay were crashes in the corridor, which increased from approximately 190 in 2013 to about 225 in 2015,” the report said.

The number of vehicles the freeway can move drops when congestion occurs.

In 2015, I-90 at Freya Street was routinely seeing traffic volumes at 79 percent of capacity at rush hour, a reduction of freeway function over 2013.

“As traffic increases and speeds drop below maximum throughput, congested roads carry fewer vehicles, resulting in a drop in throughput productivity,” the report said.

Contributing to the problem was a drop in the number of people commuting by bus. The bus system lost passengers when gasoline prices dropped a few years ago. Ridership rebounded in 2016, however.

Buses have plenty of room for more passengers. The study showed that 57 percent of seats were occupied during rush hour in 2015, compared with 61 percent in 2013.

State transportation officials are looking for ways to ease the congestion.

They have hired a private engineering firm, DKS Associates, and assigned one of their engineers to search for low-cost ways to improve traffic flow.

For more information or to provide suggestions, contact Larry Frostad, assistant traffic engineer, at frostal@wsdot.wa.gov.

CdA intersection to get $1.8M upgrade

One of the busier intersections in Coeur d’Alene, in the heart of the health care district, will get some relief with a $1.8 million upgrade this spring.

The junction of U.S. Highway 95 and Ironwood Drive next to Kootenai Health will be expanded to include more lanes on the east-west Ironwood corridor. The project is expected to ease congestion during peak commute times and improve access to the hospital and surrounding medical offices.

The Idaho Transportation Board will vote Wednesday to award the construction contract for the project, set to begin in early April and take about three months. The low bidder is Cameron-Reilly LLC of Spokane.

The project will result in two dedicated left-turn lanes, two through lanes and one right-turn lane for both directions on Ironwood. The highway there doubles as Lincoln Way.

Between 28,000 and 30,000 vehicles on Lincoln travel through the intersection daily, according to state estimates.

In addition, a new signal will be installed one block south at the intersection of Lincoln and Emma Avenue.

The project mostly is funded by the state but includes some support from the city of Coeur d’Alene and Kootenai Health.