Oregon Route 231 (Oswego-Wilsonville)

Oregon Route 231
Clackamas County Market Road #12
Route Information
Maintained by Clackamas County
Length	≈10.5 mi.
Existed	1934 to ???
Junctions
North End	US-99 in Oswego
	OR-244 in Wanker's Corner
South End	OR-217 in Wilsonville
Navigation
←  OR-230 OR-231 (1954)  →

Oregon Route 231 was a secondary state route assigned in 1934 between US-99 in Oswego (now OR-43 in Lake Oswego) and OR-217 in Wilsonville. It was designated along Clackamas County Market Road #12, but it is unknown at this time whether or not the route number was ever posted along the road. Today, the road is known as McVey Avenue in Lake Oswego, SW Stafford Road in Clackamas County, and SW Wilsonville Road in Wilsonville.

History

Clackamas County Market Road #12 was built at some point prior to 1880 and was known colloquially as the "Oswego Road," "Oswego-Wilsonville Road" and "South Oswego-Wilsonville Road". It had one major bridge over the Tualatin River, the Shipley Bridge near Wanker's Corner, that was also built prior to 1880; the original bridge was washed away in a massive storm on January 9th of that year and was replaced soon after with a wooden covered bridge. The road was paved in sections, starting north of Shipley Bridge around 1923 and completed by 1928.

After building a secondary highway system largely from county market roads in 1931 and launching the primary route system in 1932, the Oregon State Highway Department began developing a secondary route system around 1934 to run mostly along secondary highways and some of the remaining market roads. When the list was released, Market Road #12 was assigned OR-231:

Ore. 231     Beginning at a junction with U. S. 99 in Oswego; thence south on Market Road #12 to a junction with Ore. 217 in Wilsonville.

-From "Oregon State Highway Department Designated Route Numbers," c. 1934, p. 3

However, when secondary state route numbers started appearing on official state highway maps in 1936, the road between Oswego and Wilsonville did not have a route number. It hasn't appeared on any known state or commercial map from 1934 or later. No official reason for the omission of OR-231 has yet been found, but this will be a topic of future research.

This section of the 1936 official state highway map does not show OR-231 along the Oswego-Wilsonville Road.

The OR-231 number would later be reused for a stretch of former US-99 in the 1950s and 1960s.

Post OR-231 Assignment

The wooden covered Shipley Bridge would be replaced by a 160-foot steel bridge around 1938-39 at a cost of $47,400, with $21,300 coming from a Public Works Administration grant. Then, in 1958, that bridge was replaced by a 300-foot concrete span. Finally, that bridge was replaced by a 445-foot concrete structure in 2010 at a cost of $9.9 million.

It is unclear at this time when the road started becoming referred to more as "Stafford Road".

At some point, Stafford Road was realigned on a higher-speed routing to the northwest in the Stafford area. The old route now exists as the entirety of SW Gage Road and a portion of SW Newland Road.

The intersection of Stafford Road and Borland Road (Market Road #4, OR-244 from 1934 to 1952 and OR-212 from 1952 to 1980) caused long backups in the 2000s. The primary causes were because the intersection was a 4-way stop and because both roads were being used as alternatives to nearby freeways. Clackamas County replaced the 4-way stop with a roundabout opened in the fall of 2009, funded largely by a nearby church; at a cost of $4 million, it was the county's first two-lane roundabout.