It is intended to provide access between Interstate 5 (I-5) and SR 7 by passing through a portion of Joint Base Lewis–McChord, a major U.S. military installation.

The route would follow the perimeter between McChord Air Force Base and neighboring Fort Lewis, terminating at Thorne Lake in Tillicum in the west and Spanaway in the east.

[8] The county government studied eight routes for the highway and eliminated four in 1992 after being unable to reduce impacts to the Fort Lewis Logistics Center.

[11] The Federal Highway Administration issued a record of decision that approved the project in 2004, allowing for land acquisition and engineering to begin.

The project remained opposed by environmental and conservation groups seeking to limit urban sprawl and the encroachment on the habitats of endangered species.

[15] Earlier versions of the package omitted SR 704 in favor of widening other streets and addressing needs on other Pierce County highways.

[18] The coalition reports that the proposed highway would bisect the largest remnant oak woodland-prairie left in the Puget Sound area.

The second location is southeast of Lake Mondress, where the alignment skirts the northern edge of a prairie habitat mostly invaded by Scot's broom.

"[23] A contrary view was expressed by Pierce County Executive John Ladenburg, who believes that it would be "environmentally irresponsible not to build that highway,"[24] because SR 704 will lessen development in the Puyallup Valley farmlands.

A four-lane, divided highway with four intersections over its entire length,[25] SR 704 may improve access to and between the military installations by providing an exclusive roadway between Fort Lewis and McChord AFB.

It could also connect the developing industrial areas of DuPont and Frederickson as well as provide an east–west alternate thoroughfare to overcrowded[citation needed] SR 512.