sentences:  SR 544 is maintained by the Washington State Department of Transportation (WSDOT), which conducts an annual survey on state highways to measure traffic volume in terms of average annual daily traffic.Average traffic volumes on the highway in 2016 ranged from a minimum of 6,700 vehicles at the SR 539 roundabout to a maximum of 9,800 vehicles on the Nooksack River Bridge.The entire length of SR 544 is also served by Whatcom Transportation Authority bus route 71X, which connects Bellingham to Everson, Nooksack, and Sumas.