(within Salem; Hwy #72 MP 4.97-Hwy #162 MP 1.47, 3.76 miles)
"Beginning at the junction of Hazelgreen and Chemawa county roads and Pacific Highway East, OR99E, north of Salem; thence westerly over Chemawa Road to its junction with Pacific Highway, I-5, and the Salem Highway;
"Thence southerly over the Salem Highway to its junction with the Willamina-Salem Highway in Salem;
"Thence southeasterly over the Salem Highway via Front Street, Pringle Parkway, and Mission Street (in common with OR22) to its junction with Pacific Highway, I-5 and OR99E, at the North Santiam Highway Interchange in Salem."
~ ODOT, Descriptions of US and Oregon Routes, March 2007
OR-99E Business itself isn't that old of a route, but it is an incarnation of a 3-mile freeway (the Salem Freeway Highway #65) that was planned for the Salem area in 1956 as part of the National System of Interstate and Defense Highways Act. The route in question was Interstate 305, a route that was all-but-certain (and even on some maps) until it, along with the Salem Freeway Highway designation, was ceremoniously killed in 1977 in a referendum; this referendum resulted in improvements to local streets and the OR-22 bridges over the Willamette River, as well as the ensuing Parkway. Construction of the parkway began in the early 1980's and the parkway was completed around 1986. I created a map of the proposed I-305, which is below.
Now, there seems to be some confusion as to the exact routing and history of OR-99E Business. First Misconception: OR-99E Business follows the route of either the old US-99E or US-99E Business through town. For the most part, this is false; while it is true that in the center of town, OR-22, OR-99E, and what was the old Pacific Highway came together, it never followed the route of US-99E all the way through town. The old highway (labelled US-99 in the 1950's and US-99E in the 60's and 70's; it was never US-99E Business) followed Fairgrounds Rd., then the Sumner-Capitol couplet, the Marion-Center couplet, and the Liberty-Commercial couplet before simply becoming Commercial St. as it exited town; OR-99E Business follows the Salem Parkway, an entirely new route into Salem from the north, then uses the Liberty-Commercial couplet past the junction with OR-22 to the Ferry-Trade couplet before finally merging onto Mission St. The overlap would've happened from the Marion-Center couplet to the Ferry-Trade couplet on Commercial and Liberty St. Second Misconception: the OR-99E Business southern terminus is currently I-5 Exit 249, the Commercial St. ramp. It is unclear if OR-99E Business was ever routed that way, as it was the old US-99E routing through Salem and some maps indicate that it does. However, as far as ODOT's concerned, OR-99E Business is routed with OR-22 for its last 3¾ miles, and its southern terminus is currently at I-5 Exit 253. It's even mentioned on BGS's on I-5 Northbound for Exit 253.
The Salem Parkway is in indigo
Current routes in light red
Former routes in gray
Freeways are in blue
This 1972 Rand McNally map shows the proposed routing of Interstate 305. The proposal would be cancelled five years later.