Like other state highways in Michigan, M-17 is maintained by the Michigan Department of Transportation (MDOT). As a part of these maintenance duties, the department tracks the traffic levels along its roadways using a metric called annual average daily traffic (AADT). This is a statistical calculation of the average daily number of vehicles on a segment of roadway. In 2009, MDOT's surveys found that the highest AADT along the trunkline was 26,141 vehicles daily on the westernmost section near the US 23 interchange while the lowest counts were along the north–south section of Ecorse Road at 8,926 vehicles. The section of M-17 from US 23 to the western junctions with Bus. US 12 has been listed on the National Highway System, a network of roadways important to the country's economy, defense, and mobility.