(Valley Jct. to near Willamina; MP 23.06 to 27.05, 3.98 miles)
(Dayton to Jct. OR-99W; MP 49.91-52.65, 2.74 miles)
"Over the Salmon River Highway from its junction with the Oregon Coast Highway, US101, west of Otis, easterly via Grand Ronde, Valley Junction (common with OR22 from Valley Junction to the Wallace Bridge), and Bellevue to its junction with the Pacific Highway West, OR99W, north of Dayton (common with OR233 between the Lafayette Highway and the Pacific Highway West)."
~ ODOT, Descriptions of US and Oregon Routes, March 2007
OR-18 was designated at the inception of the Oregon state route numbering system in 1932, signed along two separate routes: The Salmon River Highway #39 from Otis to Valley Jct., and the McMinnville-Tillamook Highway #32 from Valley Jct. to McMinnville, where OR-18 ended at US-99W. In 1952, the entire route of OR-18 became the Salmon River Highway, coinciding with the removal of OR-14 from the state route system. OR-18's initial routing passed through the towns of Willamina and Sheridan, but a bypass was built to the south in 1957, and OR-18 was placed on that new bypass; the old highway was redesignated the Willamina-Sheridan Highway #157 and marked as OR-18 Business. In 1963, another bypass was built, this time around McMinnville and through Dayton, eliminating or shortening two state highways from the system; both OR-18 and the Salmon River Highway were extended along the bypass, and OR-233 was duplexed with OR-18 for the final 2¾ miles. That took care of an eastern terminus extension, but a western terminus extension also occurred when US-101 was rerouted between Neskowin to Oceanlake (a part of what's now Lincoln City) in 1965, bypassing the small town of Otis. The road from Otis to Neskowin was turned over to county and forest service jurisdiction, but (as far as I know) OR-18 took over the leftover 1.53 miles between Otis and the new US-101, creating the highway we know today.
OR-18 is a major road to the coast between the I-5 corridor (Portland and Salem) and the coast. In most places, it's also a narrow, undivided highway that can be fairly dangerous, especially at night. It was one of the first highways in Oregon to be labelled as a traffic safety corridor in the mid-1990s, and for good reason; not a summer goes by that a news report speaks of a tragic automobile accident on OR-18. ODOT is constantly looking at ways to improve safety along a 30-mile or so stretch west of McMinnville, including adding a median and installing rumble strips, but so far to no avail. Some sections, however, have been upgraded at least to parkway standards, and interchanges have been placed at several potential traffic nightmares, such as exits to McMinnville, OR-22 at Willamina, OR-99W, OR-18 Business, and Sheridan.
The first project that is being considered is one that would affect OR-18 between the eastern edge of the Van Duzer Forest and Willamina, near the eastern junction with OR-22. From what I have read, the highway would be widened to a four-lane highway for a couple of miles east of the Van Duzer forest, turning into a four-lane expressway through Willamina. Much of the expressway would be grade-separated, and new interchanges would exist at Grand Ronde Rd., the Spirit Mountain Casino, and Yamhill River Rd. Most driveways and roads will have access to OR-18 closed or severely limited, and the Three Rivers Highway (OR-22's western leg) will be rerouted to use the Casino offramp. I have not discovered an exact timeline, but talk has circled that some of the work could be starting in 2006. Click here to view the project website.
There is also talk that the proposed Dundee Bypass could be a continuation of OR-18, making it an even more popular route between the Willamette Valley and the Oregon Coast. Interim plans call for at least a 10-mile high-speed grade-separated bypass around Dundee and Newberg along the OR-99W corridor. The reason for the bypass is growing congestion along OR-99W, as it is a two-lane road in many places with low speed limits and many stoplights, making it inadequate as a regional corridor. While some groups, such as 1000 Friends of Oregon and Friends of Yamhill County, oppose the high-speed bypass, a majority of residents from Portland to Lincoln City support the expressway.
As of August 26th 2005, the Federal Highway Administration (FHWA) accepted ODOT's proposal of a southern bypass of Newberg and Dundee. The map at the left shows the proposed routing. It would be completely grade-separated, with partial interchanges at both ends of the bypass to OR-99W and OR-18 and full interchanges with OR-219 south of Newberg and a Dundee access road (shown). No end date for the project has been determined, but my guess is that work will begin about 2 years from now or so. Other proposals, such as a northern bypass, a regional bypass, or transit improvements, would not have the same impact as the highway is a regional corridor in dire need of overhaul to prevent accidents. Click here to view the project website.
Seeing as how most of the realignments of OR-18 are extensions, the only rerouting of OR-18 that exists is the bypassing of Willamina and Sheridan. What was OR-18 between 1932 and 1957 is shown in red and today is designated OR-18 Business. Access to OR-18 Business is only available through partial interchanges each way (exit one direction, entrance another). This section of old OR-18 is known in the state highway system as the Willamina-Sheridan Highway #157.
MILE 1: When you're almost to the coast (or just leaving US-101) you'll pass through the small town of Otis. This town was the former western terminus of OR-18, but another note of fame for this speck on the map is that in 1999 Otis was put up for sale to the tune of $3 million. Rumor has it that various celebrities were interested in buying the town, including Clint Eastwood and current California Governor Arnold Schwarzenegger. There were no takers on the offer in 1999, but it was put back on the market in 2004 for the same amount, according to KATU Channel 2 (ABC Portland).
MILES 33-35: Between mileposts 33 and 35 are the exit to Sheridan and the westbound-only OR-18 Business exit, the only exits along OR-18 that are marked with numbers (33 for Sheridan, 34 for OR-18 Business). However, other unmarked exits exist along this route, including the other OR-18 Business exit near Willamina. My guess is that the numbering is left up to the county authorities, and Yamhill county has been more proactive than other counties when it comes to numbering its exits; the exits near Willamina are in neighboring Polk county. This is an example of ODOT's attempt to number every exit in the state of Oregon, no matter what the highway. Oregon's interstate exits have been numbered since the mid-1970s.