Mileposts

This page is about the usage and evolution of physical mile markers in Oregon. For an explanation of Oregon's milepoint system, see Mileposting in Oregon.

Mileposts, also called mile markers, denote the distance between two termini on a highway or road. On state highways and county and local roads, the design and materials used for mile markers has changed drastically throughout the years.

Pre-State Highways

Portland Baseline Mile Makers

Not much is known about mileposting of roads in Oregon prior to the creation of the OSHD, but the mile markers along Portland's Stark Street (formerly Baseline Road) are some of the oldest such mileposts in the state.

After John Preston, first Surveyor General for the Territory of Oregon, marked the intersection of the Willamette Baseline and the Willamette Meridian in June 1851, a road was soon built along the baseline east of Portland. Appropriately called "Baseline Road", it was opened on November 24, 1854. Some time after that, 15 stone mileposts were placed eastward along Baseline Road from the courthouse to the Sandy River, one stone per mile, using the Multnomah County Courthouse (between SW 4th/5th Avenues and Main/Salmon Streets) as the zero milepoint. while no one is sure who placed them or when they were placed, it is believed to have been done in the 1870s by the United States Army operating out of the barracks on Front Street and Madison Avenue; they used a one-mile long rope tied to a wagon's axle to make the measurement.

Surprisingly, 9 of the original 15 markers survive today, which is even more incredible given the amount of widening Baseline Road/Stark Street has undergone the past 150 years; the downside is that none of the markers are likely in their original locations as a result. Mile markers 1, 3, 8, 10, 12 and 15 are missing; all others have been preserved, rescued and/or reinstalled at some point in their history. The plaque in Ventura Park lists mile marker 11 as missing; however, it was since recovered in 1998 and re-set in 2000 with additional concrete.

It is believed that this process was repeated for roads heading in three other directions from Portland: Northerly along St. Helens Road/Lower Columbia River Highway (present-day US-30), southerly along a road near the West Side Pacific Highway, and westerly along Jefferson Street/Canyon Road or Burnside Street. One mile marker, P7, can be found outside the Capitol Hill branch of the Multnomah Public Library on SW Captiol Highway along the supposed southern route. Otherwise, no other mile markers have been found along any other routing, despite rumors that three mile stones exist along the northerly alignment.

• P Mile Markers Around Portland
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  Baseline marker P2 embedded into a concrete wall on SE Stark Street in Portland, 2016

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  Baseline marker P7 in Ventura Park at the corner of SE Stark Street and 117th Avenue in Portland, 2013

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  Southern baseline marker P7 at the Capitol Hill branch of the Multnomah Public Library in Portland, 2013

State Highways

Concrete Mileposts

Original Mileposts

Concrete mileposts were first platted in 1913, along the entirety of the Columbia River Highway from Astoria to The Dalles. The zero milepoint was in Portland, at the corner of SW Washington Street and Broadway; from there, mileage increased both easterly to The Dalles and westerly to Astoria. They were triangular in design, about 3-4 feet tall, with the number carved into the two sides facing traffic.

The OSHC included a photo of this section 5 miles south of Salem in their Sixth Biennial Report as an example of the mileposts they placed around 1924.

In 1923, the OSHD audited its major highways, including the Columbia River Highway, to compile a list of features along the roads for recordkeeping and maintenance purposes; these lists became the 1924 "Mile Posting Data" log for each highway, a precursor to straightline charts that ODOT still uses today. The Sixth Biennial Report of the Oregon State Highway Commission, published in 1924, features a photograph between pages 78 and 79 of one such milepost, MP 58, along the Pacific Highway a few miles south of Salem; it also describes their placement along five major highways, as well as their purpose:

Concrete mile posts indicating the distance from Broadway and Washington streets, Portland, have been set on the entire length of the Pacific and West Side Pacific Highways, also the Upper and Lower Columbia River Highways and Old Oregon Trail through to Ontario. These mile posts, having been accurately set, become an interesting and informative guide to tourists as well as affording valuable aid in designating maintenance operations, etc. Supplementing the mile posts, each bridge, culvert or other structure has been measured in and indicated on the department records with the proper decimal of the mile in which it is located. This permits the immediate location of all bridges and structures.

While the report only mentions the highways that would become US-99/99E/99W and US-30, OSHD policy at the time was to place "permanent concrete mileposts on all our main state highways".

Due to realignments, widenings, theft and other reasons, very few original concrete mileposts have survived to the present day, with even fewer of them in their original locations. By 1987, only three original concrete mileposts existed along the entirety of the old Upper Columbia River Highway, with only two of them (mileposts 14 and 58) still in good condition into the present day.

In addition to the highways above, concrete mileposts have also been discovered along former and abandoned alignments of The Dalles-California Highway in The Dalles-Dufur region. The designs of these mileposts are similar to the ones found on the Pacific and Columbia River Highways; however, the points on the triangular columns of these posts appear rounder and visible stamp outlines can be made out around the numbers. This indicates that these might be newer than the ones placed on the other highways, but it's unclear by how much.

Locations

Pacific Highway

Milepost	Location	Condition	Notes	Photo
MP 146	Cottage Grove Museum	Fair	As of 2011	—
MP 268	Oxyoke Rd. near Pleasant Valley	Excellent		—
MP 269	Near intersection of Monument Dr. and Mountain Paradise Rd., Pleasant Valley	Fair/Good		—
MP 285	OR-99 near Savage Rapids Dam	Unknown	Rediscovered 2007, needs to be located in the field	—
MP 286	OR-99 east of Savage Creek Rd. near Grants Pass	Excellent	Rediscovered 2007	—

Columbia River Highway

Milepost	Location	Condition	Notes	Photo
MP 14	24400 block of Sandy Blvd. in Wood Village	Excellent	May not be in original location	(2020)
MP 58	Historic Columbia River Highway State Trail near Viento State Park	Excellent	Rediscovered 1981	(2020)
MP 70	Historic Columbia River Highway State Trail near Mosier Twin Tunnels	Replaced	Was in poor condition by 1987, likely replaced with restored milepost by 2000	—

The Dalles-California Highway

Milepost	Location	Condition	Notes	Photo
MP 3	Eightmile Rd. near Petersburg	Poor	Exposed rebar, severe cracks; used to support a birdhouse	(2021)
MP 9	Intersection of Eightmile Rd. and Emerson Loop Rd.	Good	One major crack, no chunks missing	(2021)
MP 12	Abandonned section of OR-23/US-197 off of Ward Rd. near Boyd	Good	Some small chunks missing	(2021)
MP 18	South of intersection of US-197 and Helmrich St. near Dufur	Destroyed	Appears to have been damaged beyond repair for unknown reasons	(2021)
MP 19	Abandonned section of OR-23/US-197 south of Dufur	Unknown	Needs to be located in the field	—

Unknown

Milepost	Location	Condition	Notes	Photo
MP 5	1600 block of SW Spring Garden St. in Portland	Good	Spring Garden St. was never a state highway, so this was possibly removed from the nearby Pacific or West Side Pacific Highway	(2021)

Restored Historic Columbia River Highway Mileposts

A comparison of the original CRH concrete mileposts and ones proposed by Diane Ochi in her 1981 report on the highway.

The need for milepost restoration along the old Columbia River Highway was identified as far back as 1981. In her National Park Service report Columbia River Highway: Options for Conservation and Reuse, Diane Ochi recommended adding back mileposts along the route as part of a unified signage overhaul along the route. The newer mileposts would be of similar design to the original ones, but were more informational and intricate in design and placement:

• When installed, the posts would be oriented to point to the north.
• "Columbia River Highway" would appear underneath the number, rotated clockwise 90 degrees in order to fit on the post.
• Both the number and "Columbia River Highway" would be surrounded by a rounded-rectangular border, beveled at the same depth as the letters (¼-inch).
• The installation or designation year ("1981" in the etching) would be inscribed on top of the post.

Ochi's grand vision for the new Columbia River Highway mileposts did not come to fruition, but the idea of milepost restoration along the highway lived on. By 1987, the state had allocated $10,000 to ODOT to cast and place concrete replacement mileposts along two state-owned portions of the old highway, the Crown Point Highway and the Mosier-The Dalles Highway. These mileposts were similar in design and size to the ones originally placed along the highway, but the numbers were thicker and were painted white. Later projects, including the restorations of the Ruthton Point Viaduct and the Mosier Twin Tunnels, also received these mileposts. However, it is not known at this time if recently opened HCRH Trail segments have these stone mileposts on them.

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  Restored HCRH Milepost 32 just west of Multnomah Falls, 2013

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  Restored HCRH Milepost 63 at Ruthton Point, 2019

Wooden Mileposts

An undated OSHD photo shows wooden mile marker 116 along a desolate section of the John Day Highway (OR-19) near Fossil Mountain.

At some point, the OSHD started utilizing wooden mileposts on its routes. They consisted of wooden logs buried in the ground, with the exposed part painted a light color (likely white) on top and the bottom/unexposed part painted a dark color (likely black). On the lighter part, large dark numerals were painted on the side. The top was pointed. The scope of the usage of these mileposts is unknown at this time, nor is it immediately known if numbers were painted on both sides (though it would seem likely).

MUTCD-Compliant Mileposts

1961 Standards

The 1961 edition of the MUTCD introduced mileposts into the standard, discussing their purpose, placement, zero-milepost orientation, and design. Owing to their uniformity of standards, mileposts on Interstate freeways had a very specific color scheme and numeral size:

The Milepost panels are green, with 6-inch white reflectorized numerals.

The standard allowed more leeway for non-Interstate highways, allowing three different color schemes and two different numeral sizes:

It is recommended that these be simple panels, without border, having 4- to 6-inch numerals and no other legend. The numerals should be black on a white background or white on a green or black background, with suitable reflectorization.

Aside from the colors, numeral sizes, and the lack of border and other legends (which also applied to Interstates), no other guidance was given on other aspects such as shape, size, typeface, or numeral orientation.

When Oregon implemented mileposts according to their interpretation of the 1961 specification, they used green metallic panels 24 inches tall and 8 inches wide, with 6-inch numerals center-aligned descending from the top of the panel. The numerals were in reflectionized FHWA Gothic Series E and were not rotated. The panel was the same size regardless of how many digits were on it and the type of highway it was placed on. Almost none had borders on them.

The prevalence of these mileposts along state highways diminished in the 1980s and 1990s due to reconstruction projects and updated reflectionization standards; as a result, very few of these mileposts remain, occasionally on former state highways turned back over to county control:

• On US-101 in Depoe Bay, two could be found at MP 128 as of 2016. Both were in good condition.
• One can be found on OR-47 outside of Mist at MP 49 as of 2021. It was in excellent condition.
• One can be found on OR-99E just north of Hubbard at MP 28 as of 2019. It appeared to be in good condition.
• A few can be found on OR-210/Scholls Ferry Road between Kinton and Scholls at MP 2 and 3 as of 2021; MP 4 was present into the mid-2010s. All appeared to be in poor condition, but could also just have been extremely dirty.
• A pair could be found on OR-8 at MP 1 in Beaverton until the late-2010s. These ones were unique in that they had a border around them, a deviation from the 1961 spec. The westbound one was removed sometime around 2017 and the eastbound one around 2020. Both have since been replaced with modern mileposts. Prior to removal they were in good condition.

Others may still exist elsewhere in the state.

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  A pair of 1961 spec mileposts mounted on a single post at MP 128 on US-101 South in Depoe Bay, 2016

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  A single 1961 spec milepost at MP 49 on OR-47 North near Mist, 2021

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  A single 1961 spec milepost (with added border) at MP 1 on OR-8 West in Beaverton, 2015

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  Another 1961 spec milepost milepost at the same spot eastbound on the same highway, 2018

1971 Standards

AASHO revamped their standards in 1971, tightening up the variances in color, shape and size previously allowed. Also, borders and the word "MILE" were added in a complete reversal from the 1961 spec. The previous requirements for Interstates were rolled into general requirements for freeways in this edition, and required larger mileposts:

Markers shall contain 10-inch white numerals on 12-inch wide vertical green panels with a white border. Panels shall be 24″, 36″, or 48″ in length for one, two, or three digits, respectively, and contain the word MILE.

Markers on non-freeways were just smaller versions of the freeway ones:

Milepost signs shall be vertical panels with 6-inch white numerals, a border and the word MILE in 4-inch letters on a green background and shall be reflectorized.

Three sizes were specified, based on how many numbers would be on the post:

• D10-1: For 1-digit numbers, 12″ × 24″ on freeways, 10″ × 18″ elsewhere
• D10-2: For 2-digit numbers, 12″ × 36″ on freeways, 10″ × 27″ elsewhere
• D10-3: For 3-digit numbers, 12″ × 48″ on freeways, 10″ × 36″ elsewhere

Aside from the size of the numbers and the MILE legend, no typeface suggestions were given. However, the example image in the MUTCD itself appears to use FHWA Gothic Series D for the numerals and Series B for the MILE legend.

Oregon mostly adopted the milepost standard as defined in the MUTCD. However, the state opted to use the D10-2 2-digit marker for 1-digit mileposts, with the number vertically centered between MILE and the bottom of the post. This practice was utilized on both freeway and non-freeway routes through the mid-2000s, when ODOT started using the D10-1 marker more frequently for single-digit mileposts. Recently completed transportation projects, like the Sunrise Expressway and the Rogue Valley Expressway, use D10-1 single-digit panels.

Two of Oregon's first major implementations of the 1971 standard mileposts occurred around early 1972, when the entirety of mileposts on Interstates 5 and 80N were replaced. Interstate 5's mileposts were originally from north to south, but needed to be switched to running south-to-north, per 1961 AASHO standards; Interstate 80N's mileposts were being changed to incorporate increased mileage from the selection of the Mount Hood Freeway corridor. State Highway Engineer R. L. "Rod" Porter estimated that the cost of revising both highways' milepost systems and installing the new mileposts would cost $25,000 total — $11,500 for I-5 and $13,500 for I-80N — and would need to be done with state forces instead of by several contractors.

Technically, just about any milepost on a state highway in Oregon that only includes a border, a MILE legend and large numbers on whole miles is a 1971 specification MUTCD milepost. That said, Oregon does have quite a few subtle variations based primarily on number size and typeface, usually FHWA Series C or D. In addition, later MUTCD specs included variations that Oregon has implemented from time to time.

2003 Standards

The 1971 MUTCD descriptions for mileposts remained more or less the same for more than 30 years, even after a name change to the more generic "reference posts" in 2000. These standards also allowed for fractional mileposts of some kind, using either delimiters or reference posts at consistent intervals. However, they weren't considered part of the milepost system until 2003, when AASHTO introduced them as "intermediate reference location markers". These mileposts have the same design as the 1971 spec, but with an extra section below the mile number that contains the fractional portion, with decimal (such as ".3"). The decimal portion is always displayed, even on whole numbers where a ".0" is placed in that section.

The 2003 MUTCD defined sizes for freeway and expressway placement, but not for other highways and roads. Their dimensions are estimated based on the original D10 mileposts of comparable size.

• D10-1a: For 1-digit numbers – 12″ × 36″ on freeways, 10″ × 27″ elsewhere
• D10-2a: For 2-digit numbers – 12″ × 48″ on freeways, 10″ × 36″ elsewhere
• D10-3a: For 3-digit numbers – 12″ × 60″ on freeways, 10″ × 45″ elsewhere

Oregon's first implementation of this standard, however, was not for fractional mileposts. Instead, the mileposts were used to differentiate between sections of US-395 where mileposts reset to zero due to Oregon's dual highway/route system. This resetting confused travelers at best and hindered emergency services at worst, so ODOT decided to add letters in the spot on the post where the fraction would normally reside. ODOT initially added them on two sections in late 2008 or early 2009 — the section of US-395 from Pendleton to Mt. Vernon received "B" while the section from John Day to near Burns received "C". Letter suffixes "D" and "E" were added to two portions from near Riley to the California border by 2013; these ones omit the line between the numbers and letter, making them effectively like an original D10 milepost with 4 alphanumerics on them.

The letter suffix system was expanded to OR-207 by early 2018, using "A", "B" and "C" along three different sections.

As far as actual fractional mileposts are concerned, their first usage in Oregon was on US-26 between Sandy and the junction of OR-35, installed at half-mile intervals in the summer of 2011 as part of and ODOT pilot project. Since then, Oregon has expanded their usage on other highways to improve response times. Freeway-size D10-2a markers has been installed at half-mile intervals in the median of I-84 through the Columbia River Gorge, and smaller D10-1a mileposts were installed on the Multnomah County section of then-future OR-127 in the summer of 2019. Oregon also has placed a D10-2a marker at MP 68.9 along US-26 near Clear Creek in the Mount Hood National Forest in an attempt to avoid the "Mile 69 Problem".

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  A D10-1a milepost at MP 9 on OR-207 near Hardman, with a letter suffix to distinguish between three sections of the same route, 2021

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  A D10-1a milepost at MP 3.5 on Cornelius Pass Road (now also OR-127) just north of the intersection with Skyline Blvd., Multnomah County, 2020

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  A D10-2a milepost at MP 27.0 on US-26 east of Sandy, 2017 (since replaced with a standard D10-2 marker)

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  A D10-2a milepost at MP 36.5 on US-26 west of Mt. Hood Village, 2017

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  A D10-2a milepost at MP 68.9 on US-26 near Clear Creek, 2021

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  A large D10-2a milepost at MP 31.5 on I-84/US-30 at Multnomah Falls, 2021

2009 Standards

The 2009 standard added another milepost type, "enhanced reference location signs", to further aid motorists and emergency responders. These mileposts contained a cardinal direction, route shield and whole mile number. Two different varieties were defined, one for whole numbers (D10-4) and one for fractional miles (D10-5) which included an extra section below the mileage for the decimal part. Both varieties only came in one size, regardless of mile number or highway type:

• D10-4: For whole miles only – green or blue, 18″ × 54″
• D10-5: For whole and fractional miles – green or blue, 18″ × 60″

Legends need to be at least 6 inches tall and shields need to be at least 12 inches tall. For typefaces on both, the examples in the MUTCD showed the cardinal direction and whole mile number in FHWA Series B, and with "MILE" and the fractional mile (if present) in Series C.

Oregon doesn't use these type of mileposts very often, but they are present in the state. D10-5 markers were installed at half-mile intervals along OR-217 in the summer of 2011 as part of the same pilot project that installed 2003-spec D10-2a markers along US-26. These markers largely matched those in the MUTCD, but used FHWA Series C for the whole mile number instead of Series B. As of 2021 they do not appear to have been implemented along any other freeway within Oregon.

In addition, D10-4 mileposts can be found in a rare non-freeway instance intermittently along US-20 through the Cascades. Installed around 2016 or 2017, these ones more or less follow the MUTCD example typeface-wise. Some examples can be found at MP 75, MP 80 and MP 83.

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  A D10-5 milepost at MP 2.5 on OR-217 South in Beaverton, 2021

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  A D10-4 milepost at MP 80 on US-20 East in the Cascades, 2017

Miscellany

A rare zero milepost at the northern terminus of OR-551 at I-5 south of Wilsonville, 2020

• Oregon posted zero mileposts in two locations in the late 2010s: At the northern terminus of OR-551 and at the junction of I-5 and OR-99E Business in Keizer. These are possibly the first zero mileposts along a state-maintained highway in Oregon.
• Rarely, some mileposts will have a "Z" above the number, such as on a section of US-101 near Wheeler. This is due to a highway realignment or cancellation and is used to denote duplicate mileposts along a highway, and is similar to "B"-mileage in Washington or "R"-mileage in California. For additional information on Oregon's milepoint system, see Mileposting in Oregon.

County Roads

Clackamas County

Three different kinds of mileposts can be found on Clackamas County roads:

• Green MUTCD D10-2 mileposts for 1- and 2-digit numbers, marked at whole miles
• White metallic rounded rectangles, marked at culverts in hundredths of a mile
• White delineator wickets embedded in the ground, also marked at culverts in hundredths of a mile

Each of these mileposts contains the mileage and a 5-digit county road number. This number can sometimes span two different roads if they comprise a longer route, such as Stafford and Wilsonville Roads.

The green mileposts used to be more prevalent in the 1990s but have been disappearing as they're damaged or otherwise removed. The white markers are much more prominent, but can be more hidden and sometimes don't face traffic.

At jurisdictional boundaries, the white markers can also sometimes be found with "BCM" and "ECM", for "begin county maintenance" and "end county maintenance" respectively, depending on the direction of travel. Metal rectangle versions of these posts can also contain the county road number.

Zero mileposts can be found among all three types, though the green ones are much rarer.

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  A D10-2 milepost at MP 1 on SW Mountain Rd. near Stafford, 2013

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  A white rectangular milepost on SW Homesteader Rd. near Stafford, 2013

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  A white wicket milepost on SE Fireman Way in Boring, 2017

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  A white rectangular milepost on E Salmon St. near Brightwood, 2017

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  A damaged D10-2 milepost at MP 4 on SW Borland Rd. near West Linn, 2017

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  A white "begin county maintenance" marker on SW Ladd Hill Rd. near Sherwood, 2020

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  A white "begin county maintenance" wicket on SW Carman Dr. in Lake Oswego, 2021

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  A white "end county maintenance" wicket on SW Carman Dr. in Lake Oswego, 2021

Clatsop County

Mileposts

Prior to the mid 2010s, mileposts on Clatsop County roads appeared only on green wickets placed in the vicinity of a culvert. These wickets only show the mileage in hundredths of a mile, without identifying any sort of road name or number. The typeface used is a thinner stroke version of Helvetica Inserat Roman.

In early 2015, some roads were provided with mileposts in three new distinct styles, leaving the green wickets intact:

• A standard D10-1 or D10-2 milepost, mounted on a post in the center, with some additions:
  • The 2-digit year of manufacture or installation is in black in the upper right
  • The road name and number are in white on the bottom towards the left
  • "Clatsop County" is in black on the lower right
• A different D10-1 (and possibly D10-2) milepost, mounted on a post to the side, with the road name and number on the bottom as the only additions; the number on these ones are FHWA Series B, vs. Series C or D on standard D10 markers.
• A white wicket with a green sticker stating "MILE" and the mile number; all letters and numbers are condensed FHWA Series C

Other variations may also exist, but have yet to be discovered or documented.

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  A centrally-mounted D10-1 milepost at MP 1 on Lower Nehalem Rd. south of Elsie, 2018

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  A side-mounted D10-1 milepost at MP 5 on Lower Nehalem Rd., 2021

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  A centrally-mounted D10-2 milepost at MP 10 on Lower Nehalem Rd. near the Tillamook County line, 2021

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  A white wicket milepost at MP 1 on Red Bluff Rd. near Elsie, 2021

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  A white wicket milepost at MP 6 on Hamlet Rd. near Hamlet, 2021

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  A green wicket milepost at MP 9.02 on Lower Nehalem Rd., 2014

Bridge Inventory Markers

This section is under construction. Check back soon, as it will be updated frequently.

Columbia County

Columbia County does not place mileposts along all of its roads, but does on some major ones like Apiary Road and Scappoose-Vernonia Highway. When they are placed, they are standard D10-1 and D10-2 mileposts with the numeral in FHWA Series D. No other markings or information appears to be on the signs themselves.

Coos County

Coos County has used their own version of an "enhanced" milepost for at least 20 years, though overall it appears more in line with the 1961 MUTCD spec. It consists of a simple green rectangle 6″ × 18″ with no border or "MILE" legend, with a FHWA Series C numeral roughly centered at the top of the sign. Below the numeral is a square sticker of a Coos County reassurance shield with the road number placed on top. The road number is also in Series C, but the "COOS COUNTY" inside the shield appears to be different weights of Helvetica Neue LT Pro; "COOS" is in 87 Heavy Condensed and "COUNTY" is either 77 Bold Condensed or 67 Medium Condenseed.

Hood River County

Marion County

Marion County doesn't appear to put mileposts along its county roads.

Multnomah County

Multnomah County has used standard D10-1 and D10-2 mileposts along its roads since at least the mid-1980s, though they used to be more common than they are now. The large numerals are usually in FHWA Series C, but can also be found in Series D. They are commonly mounted on wooden posts with the top carved into a point, a typical feature of Multnomah County signage.

The county did place D10-1a mileposts at half-mile intervals along Cornelius Pass Road in 2019, but this was likely done in conjunction with ODOT in preparation to turn it over to state jurisdiction. Curiously, Multnomah County milepost 5 still remains on Cornelius Pass Road at the Washington County line as of May 28, 2021.

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  A D10-1 milepost at MP 2 on SE Orient Drive (old OR-50/US-26) in Orient, 2017

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  A D10-1 milepost at MP 5 on Cornelius Pass Road (OR-127) on the Multnomah-Washington County Line, 2021

Tillamook County

Umatilla County

Umatilla County appears to place D10-1 and D10-2 mileposts along many of its county roads. The designs are slightly modified from the standard to place "UMATILLA COUNTY" in small FHWA Series C text centered below the numeral on two separate lines, but are otherwise the same as other 1971 MUTCD spec mileposts. No other road information appears to be present on these signs.

Wasco County

Wasco County doesn't appear to put mileposts along its county roads.

Washington County

Mileposts

Mileposts along Washington County roads are pretty rare and usually aren't present at all. When they are, they are simple green rectangles 6″ × 18″ with no border, with "MP" and the number in the same size FHWA Series B typeface. They are usually — though not always — accompanied by a smaller green rectangle 6″ × 10″ with a thin white border bearing the text "WASHINGTON COUNTY ROAD" and the road number, both also in Series B. Due to their weathered appearance in the wild, it's likely these mileposts were placed more than 30 years ago. Only a handful are known to have survived into the 2010s:

Road	Milepost	Location	Status
SW Bull Mountain Road (Washington County #20272)	MP 2	Intersection with SW 150th Ave., Tigard	Removed sometime after February 2015
SW 185th Avenue (Washington County #35185)	MP 3	Across from Burnside Park, Aloha	Removed sometime after October 2014
River Road	MP 3	South of intersection with Rosedale Road, near Hillsboro	Present as of May 2021, but missing its road number plaque and possibly the "MP" legend
NW West Union Road (Washington County #52626)	MP 4	Pair of mileposts at West Union Elementary school, near West Union	May have been removed
NW West Union Road (Washington County #52626)	MP 6	Between intersections of NW 208th Avenue and NW 205th Terrace, near West Union	Present as of October 2020

Others may still exist along Washington County backroads.

Older state mileposts can also be found on sections of state routes turned back over to county jurisdiction. 1961 MUTCD specification posts are present as of 2021 at MP 2 and 3 along OR-210/Scholls Ferry Road; MP 4 near Kinton was present until the mid-2010s. A 1971 spec MP 12 also exists at the north end of Scholls Ferry Road near OR-10/Beaverton Hillsdale Highway. On OR-10/Farmington Road, a 1971 spec MP 3 was present eastbound as of August 2018; a 1961 spec milepost at that same location westbound was removed sometime after 2002, and other 1971 spec mileposts were removed over a 10-15 year period after that section of OR-10 was relinquished to the county.

Curiously, Washington County placed a D10-1 standard "MILE 1" marker on Scholls Ferry Road in Scholls at milepoint 1 of the old Scholls Highway #143 when the Tualatin River bridge was rebuilt in 2008. These markers — possibly the only MUTCD standard mileposts placed by Washington County — replaced a 1971 spec marker eastbound and a 1961 spec marker westbound.

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  Milepost 2 at the intersection of SW Bull Mountain Road & 150th Avenue in Tigard, 2015 (since removed)

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  Milepost 6 on NW West Union Road near West Union, 2020

Bridge and Culvert Markers

Washington County also marks most of its bridges and culverts with markers similar to the county road identifiers on mileposts, with the word "ROAD" replaced with "BRIDGE" or "CULVERT" appropriately. The numerals are larger than the road markers, and the legend text appears to be less condensed. Numerals are usually still in Series B, but Series D has been observed on . No other mileage or route identification information can be found on these markers. A newer version of this marker was placed on the Scholls Ferry Road bridge over the Tualatin River when it was replaced in 2008.

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  A Washington County bridge marker on Cochran Road near Reehers Camp, 2019

Yamhill County

Yamhill County doesn't appear to put mileposts along its county roads.