Glossary

Learn more about tolling terms used on this Web site and in other documents about tolling.

Active Traffic Management

Technology can help reduce congestion and increase safety by giving information and guidance to drivers about traffic conditions. Examples include overhead signs in each lane to slow drivers in advance of a bottleneck, or that provide real travel times and guidance about suggested lane changes or reroutes.

Bridge Toll

A fee collected to help pay for a specific bridge project. One example is the toll on the new Tacoma Narrows Bridge.

Directional Toll

A toll rate that is higher during peak hour in the peak travel direction.

Congestion

Congestion is defined as vehicles traveling less than 30 miles per hour. Congestion is either recurring or the result of a traffic incident. Recurring congestion stems from the high number of vehicles using I-5 at key travel times. The effects of bridge lifts, stalls and collisions lead to incident congestion. Both types of congestion lead to unreliable travel times for all travelers.

Electronic Toll Collection

Collecting tolls without the use of toll booths, generally with transponders. Drivers do not need to slow down or stop to have their toll collected. Also known as open road tolling.

Fixed-rate Toll

Toll remains the same throughout the day.

HOT Lanes

HOT (high occupancy toll) lanes offer an option for solo drivers to access high-occupancy vehicle (HOV) or carpool lanes to enjoy a more reliable trip. Generally, this fee is dynamic; toll rates change with traffic levels to ensure that cars in the lane move at or above a set speed. In Washington, the first HOT lanes pilot project recently opened on SR 167.

Variable Tolling

Toll rates that vary by time of day based on a set schedule.