 It is mainly used by commuter traffic within Marysville and traveling to I-5 and SR 9, becoming congested during rush hours as a result.The Washington State Department of Transportation (WSDOT) conducts an annual survey of traffic volumes on state highways measured in terms of average annual daily traffic.Traffic volumes on SR 528 range from a minimum of 14,000 vehicles at SR 9 to a maximum of 33,000 vehicles at the I-5 interchange.