Just north of Valley View Drive, it passes the Sanford Clear Lake Medical Center.

Just south of 5th Street West, it passes Deuel Public School.

Just north of 3rd Street West, it passes the Clear Lake Historical Society Museum.

Just north of 2nd Street West, it passes the city's library, which is in the municipal building.

At the intersection with the western terminus of 181st Street leads to Ulven Park and the Deuel Athletic Complex.

Just south of 180th Street, the highway passes the Clear Lake Municipal Airport.

Just south of 174th Street, the highway passes the Altamont State Public Shooting Areas.

Just to the west of 486th Avenue, it travels just north of a sewage disposal pond just before entering Wilmot.

Just east of 3rd Avenue, the highway crosses some railroad tracks of BNSF Railway.

Just to the west of 466th Avenue, SD 15 crosses over the North Fork Whetstone River again.

Approximately 3⁄4 mile (1.2 km) later, it meets its northern terminus, an intersection with County Road 34 (458th Avenue) and the eastern terminus of CR 17 (137th Street), Originally, SD 15 traveled the entire north–south length of the state, from Nebraska to North Dakota, on the auto trail known as the King of Trails.

By 1932, the only portion of this highway that remained was from US 12 to the North Dakota state line.

After US 77 was decommissioned in the state in the early 1980s, SD 15 then extended along its former alignment south from Milbank, to the present southern terminus.

In the early 1950s, the alignment of SD 15 was adjusted to add a segment between Milbank and Wilmot.

It was established in the early 1960s, from US 12 in Big Stone City to SD 15 southwest of Shady Beach.