Two years after the Interstate 405 Express Toll lanes were installed, the state says the toll lanes appear to be saving drivers time on average. But WSDOT says one key benchmark is being missed.

The legislature required WSDOT keep traffic moving at least 45 mph for 90 percent of peak periods. Not all sections of I-405 meet that requirement. Single lane sections are only hitting the target 72 percent of the time, according data recorded through the end of June. WSDOT says these numbers are improving.

The slower speeds will be discussed in the next legislative session in January, where state lawmakers could vote to shut them down.

A new report from WSDOT suggests 70 percent of drivers use the toll lanes at least once a month. Also, the toll lanes saved an average of 11 minutes in the southbound direction, and 14 minutes northbound.

The average toll for drivers was $2.04, according to WSDOT. The average was $2.96 at peak times.

I-405 Express Toll Lanes Executive Summary by KING 5 News on Scribd