SR 17 between Eltopia and Mesa was replaced by US 395 in 1979 as part of a larger series of projects in the area to improve the highway in Franklin County.

[3] The highway travels northwest through Mesa, where it crosses over a BNSF rail line and runs through Esquatzel Coulee before intersecting the terminus of SR 260 west of Connell in the Paradise Flats.

[9] The roadway expands to four lanes and turns north at Pioneer Way, where I-90 Business leaves the concurrency and travels into Downtown Moses Lake.

The highway continues north and passes Ephrata Municipal Airport before it intersects SR 28 in Soap Lake.

[13] The roadway enters Sun Lakes State Park and passes Dry Falls at the north end of the Grand Coulee.

From Sims Corner, the roadway follows East Foster Creek northward to the western terminus of SR 174 and its spur route in Leahy.

The steel continuous riveted deck truss bridge, listed on the National Register of Historic Places,[15] carries SR 17 into Okanogan County and the Colville Indian Reservation, west of Bridgeport State Park.

[26][27][28] The Soap Lake–Coulee City branch of PSH 7 was established in 1937 to serve as an alternate route to SSH 2F, avoiding the Grand Coulee Dam.

[41][42] No major revisions to the route of SR 17 have occurred since 1979,[43] as WSDOT has improved the sections of the highway through widening and barriers.