Barriers on I-5 won’t bring a change in speed limit between Marysville and Smokey Point

Published 12:01 am Monday, August 29, 2011

John Hardy of Tulalip writes: Now that concrete barriers have been installed between the north and south lanes of I-5 between Marysville and Smokey Point, has there been any consideration to returning the speed limit to 70 mph?

Bronlea Mishler, a spokeswoman for the state Department of Transportation, responds: We made the decision in 2005 to lower the speed limit between Marysville and Smokey Point because of commercial development along I-5 and population growth in nearby cities.

In the past 20 years, traffic volumes have doubled in this area and will likely continue to increase in the future. For this reason, we have no plans to raise the speed limit to 70 mph.

North of Smokey Point, I-5 travels through a fairly rural area with fewer interchanges and lower traffic volumes. South of the Smokey Point-Highway 531 interchange, traffic volumes on I-5 increase by 40 percent and the freeway travels through residential neighborhoods, commercial and industrial areas. Drivers also are likely to encounter congestion and merging traffic at five freeway interchanges.

Emory Lane of Arlington writes: I’m curious why Highway 531 in Smokey Point was assigned an odd number. My understanding is that east-west routes are assigned even numbers and north-south routes are given odd numbers. Yet on either end of Highway 531 (172nd Street NE) and between each starting point there are signs posted “east” and “west” respectively.

Mishler responds: Emory is correct that Highway 531 is, indeed, an east-west highway, even though it has been assigned an “odd” number. It got the unusual designation on April 1, 1992 (seriously), when the state took over the highway from Snohomish County.

Highways connecting to an interstate begin with the first number of the interstate, increasing from south to north. Highway 500 connects to I-5 in Vancouver, Highway 548 is in Blaine, and anything in between has to fit into the numbering system.

When 172nd Street NE became a state highway, the numbers 524 through 532 (both even and odd) had already been assigned to other highways in Snohomish County, except for 531. Even though the highway is south of 530 and 532, and even though it runs east-west, the only number we could give it was an odd one.

For more information on highway numbering, go to http://tinyurl.com/43geref.

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