When complete, the Cross-base Highway (SR 704) will provide regional travelers with a new six-mile-long, multi-lane divided highway beginning at the I-5 Thorne Lane Interchange at the west end, connecting to 176th Street at SR 7 at the east end.

This new alternate east-west route will ease congestion on I-5, SR 512, SR 7, Spanaway Loop Road, and 174th Street, by providing a route through the Fort Lewis and McChord military bases.