INDOT’s Reference Post System

In 1999, the Indiana Department of Transportation decided that it was time to come up with a system that would help better keep track of features along the roads that for which it was responsible. While is would be based, according to INDOT, on the mileage of the road, it was not a milepost system. It was a locator for maintenance items, other than signs, on the state highway system.

RPS 86 on US 40, Marion County, Indiana (Washington Park Cemetery). From Google Maps, snipped 23 December 2020.

There are many parts to the system. The one that most people would have seen, but not really noticed, were the signs that were put up for use with the system. These consisted of small blue signs with a mile number on it, with a smaller sign, if needed, below it with an offset to that mile on it. The signs themselves were barely wider than the post they were on. Very small in relation to most highway signs. Since they are technically only for INDOT use, their size wasn’t a concern. The public wouldn’t notice them, lessening the sign pollution that departments of transportation have been trying to keep under control forever.

RP 88, Offset .88, US 40 bridge of Buck Creek, Cumberland

I really wish I could have had a better snippet for the offset post, but then, the idea was to give the reader the image of what they roughly look like, so the reader would know what to look for.

The RPS manual is very detailed in its information. For instance, the picture to the left is listed as “RP_U_40_Post_86,” meaning “Reference Post, US 40, Post 86.” The one on the right is listed as “CUMBERLAND CORP. LINE BR 4588 O BUCK CREEK,” at least in the 2004 manual.

US 40 is a very prime example of why this system isn’t to be used as a mileage post system. The system was setup prior to the 1 July 1999 decommissioning of US 31, SR 37 and US 40 inside the Interstate 465 loop. What was, in 1999, marked as mile 86 on US 40 is, in 2020, at mile 92.37 on that very same road in 2004. In 2016, the last update from INDOT, it was listed as US 40 mile 65.179. The legal definition of US 40 was lengthened when it was rerouted along the southside of Indianapolis on I-465 in 2004. By a little over six miles. By 2016, the extra mileage along I-465 was removed to show a more accurate road mileage count towards INDOT’s limit of 12,000 miles.

But there is a bit more to the reference post system that comes into play. Each highway listed in the RPS not only includes the complete mileage for the road in Indiana, but they are also listed by the mileage per county, as well. For instance, reference post 86 above is listed as Marion County mile 24.06 in 2004. In the 2016 manual, that mileage is 5.027.

Then, the reference post system records almost everything along the road. This includes EVERY village/town/city street that intersects with the posted road. For instance, near reference post 86 is, in the 2004 manual, “86 + 0.21 24.52 IR 4193 LT (DELBRICK LN).” At reference post location 86.21, 24.52 route miles into Marion County, Delbrick Lane connects to Washington Street (US 40) on the left (north) side of the road. Directions are listed from the increasing number of the reference post. Every street is listed, although almost none of them have a reference post sign.

Also, the corporation limits of towns and cities are listed by the reference post location, although there is no reference post installed most of the time. This even includes old corporation limits. For instance, in the 2016 manual, reference post 85+0.686 is listed as “City or Town Limit – Indianapolis.” Post Road is reference post 86+0.668. Legally, Indianapolis continues for another at least two miles (the sign welcoming one to Indianapolis is west of German Church Road, the county line is another mile east of that, but that is in the town of Cumberland. And even legally, Cumberland is part of Indianapolis. It is as confusing as all get out, but suffice it to say, for the past 50 years, the city limits of Indianapolis have been the county limits of Marion County, with some exceptions. Certainly not Post Road.

But the idea of the legal multiplex of I-465 with almost every INDOT road in Marion County (there are two that don’t mix with I-465: US 136 and SR 135) that brings up another question. What about multiplexes of state roads?

When the system was created in 1999, it was designed with a hierarchy of roads. That hierarchy was interstate, US highway, then state road, in that order. INDOT does not use the term “multiplex” officially. It is called “travel over” in Indiana. The following picture comes from the INDOT RPS guide of 1999 showing how “travel overs” are handled when it comes to marking the mileage of the road.

Indiana Department of Transportation Reference Post System Users Guide, May 1999.

As you can see, near Frankfort, US 421 takes precedence with the little blue signs. SR 39 is junior to SR 38 when it comes to the signs, only due to the fact that 38 is before 39 numerically.

The system underwent some changes between 2004 and 2015. In 2015, it was made perfectly clear that the manual may contain some mistakes, but that every effort was taken to avoid them.

There was also a special note involving US 40 in Vigo County. When US 40 was removed from most of Vigo County, and rerouted along I-70 and SR 46, the RPS system was not changed to reflect that. The section of US 40 that “travels over” SR 46 is still labelled as SR 46. Here is INDOT’s explanation: “US 40 in Vigo County has a special issue that needs to be addressed. Due to relinquishments and creating a travel over for US 40, the alignment does not follow the historic path. US 40 now traverses where SR 46 has traditionally been and SR 46 is considered the Travel Over on US 40. However, the existing reference posts are still for the SR 46 route and are running in a contrary direction to the increasing direction of US 40. Therefore, for the purposes of this book, RP and Offset for the first 3 miles of US are based on the State Log Measure until it reaches the traditional location for US 40 and then jumps to RP 11 + 00 at the intersection of SR 46 and US 40.”

I mentioned above about the original system being put in place prior to the decommissioning of routes in Marion County. It is important to note that there were more routes affected than just those that were moved to I-465. Those routes were US 31, SR 37 and US 40. The mileage on those roads got weird, yes. But there were two others that were affected by the change…and one most people didn’t even realize.

SR 135 was rerouted from Troy Avenue to Thompson Road, cutting two miles out of the official route. This just required moving the little blue signs from north of Thompson Road, and surveying what else would need signs. And what wouldn’t.

The other route affect wasn’t even marked when it was decommissioned. Shadeland Avenue on the east side of Marion County was still legally SR 100 from I-465 to US 40 (Washington Street) until 1 July 1999. For the longest time, the only marker on SR 100 was a smaller blue sign below the reference post signs that read “100.”

INDOT has available on their website the RPS manuals for 2004, 2015 and 2016. Also available is the users guide from 1999. Here are the links for each: Users Guide200420152016

Straightening of SR 135 in Northern Washington County

Sometimes, the state moves very slowly when it comes to improving routes that, well, from first glance, should have been higher on the priority list. When SR 35 was created with the Great Renumbering of 1 October 1926, a lot of the route was pretty straight forward. That was until you got to just south of the Muscatatuck River in Washington County. Here, the road was the definitive hilly road.

Monroe Township, Washington County
1878

And the road had been that way for a long time. The 1878 map snippet shown to the left shows the Millport Ferry, which was in the location, roughly, of the current SR 135 bridge over the Muscatatuck River. From there, the “direct” route to the next post office, that being at Millport, winds its way through the hilly territory south of the river.

And this routing hadn’t changed. Until the Indiana State Highway Commission started designing a new road to replace the old one in 1954. Yes, nearly three decades after it became a state road, SR 135 (formerly SR 35) was getting some work to make it safer for travelers.

The bridge just west of the old bridge at the location of the old Millport Ferry was opened for bidding in September 1954. The design of the bridge was to be of seven spans, 28 foot of right of way for drivers, and 26 inch pedestrian walkways on each side. The bidding, opened on 21 September of that year, only included the bridge itself. Approaches to the bridge were to be let in another contract. It also didn’t include the tie in to the then current road north of the river.

The bridge that was being replaced had been contracted in 1883. The superstructure of that bridge, to be built completely of iron, was contracted to cost $23.00 a linear foot.

Work on the design of the new SR 135 section was completed in March 1954. According to the Seymour Tribune of 18 March 1954, “It is understood plans for the new highway are normally straight, with the new location scheduled to eliminate the present many curves on the highway, which now has about 40 turns, many of them sharp, in less than two miles.”

Construction on the new section of the road began on 6 June 1955, and according to the Jackson County Banner of 3 August 1955, was expected to “be completed about the first of next year.” The contract connecting the new SR 135 to the new Millport Bridge would be let later, as the bridge had not been completed by that time. Until that bridge was complete, the old bridge would be in use, and the new SR 135 would connect to the old SR 135 just south of the new bridge. The following Google Map snippet shows the old road, the connection to the new road, and the location of the old bridge.

The new section of road would open in mid-December 1955. The entire route was concrete, with the exception of the south approach to the new Millport bridge, which was graveled to allow traffic access to the new bridge. The gravel would be replaced with concrete the following summer. The old iron Millport bridge would be removed soon after the opening of the road.

Bicycling the Three Notch Road

In the late 19th Century, when the bicycle was taking the world by storm, Indianapolis became such a “wheelman” city that it even had a “bicycle row,” along Pennsylvania Street, where most of the bicycle shops were. And one of the most favorite routes for bicyclists to live their hobby was the Three Notch Road. That is, as long as it wasn’t where the road started. More on that in a minute.

The Three Notch Road, of Leavenworth Road, which I covered here, was the route that connected Indianapolis to the rural areas of Brown County, including Nashville, before there was a state highway system. When SR 35 (later 135) came into being in Marion, Johnson, Morgan and Brown Counties, at the Indianapolis end it would have signs posted about how to get to Brown County State Park along the route.

Most of the information for this post comes from the Indianapolis News of 4 April 1896. This is a continuation of their series of information for the bicyclists.

The Three Notch Road was a continuation of Meridian Street. According to the News, it “has always been a favorite ride for the Indianapolis wheelmen. It is comparatively level, and nearly always in excellent condition. There is more shade along this road than is found on many of the turnpikes leading out of the city, and it passed through one of the most fertile regions of the county.” The route is recommended for both short and long rides, and it is also recommended that one go out the Three Notch Road and back the Madison Road.

The old road started at what was then the edge of Indianapolis, the Belt Railway. On the north side of the Belt, there was (and still is) a branch off the road. The branch lead off to Waverly along the Bluff (or Paoli State) Road. Once crossing the Belt, the Three Notch became basically impassible south to the crossing of Pleasant Run (about a mile). The description in the newspaper actually reads “it is supposed to begin at the Belt railway crossing, but for a mile south of that point it now little resembles a gravel road. Judging from its current condition, it will be weeks before the road between the Belt and Pleasant run will be fit for a wheel.”

The crossing of Pleasant Run was almost to what was, for the longest time, the city limits on the south side of Indianapolis. That line was at Southern Avenue, the reason that the street was named that in the first place. A bridge was under construction of the creek at the time of the article. Most of the route was relatively flat, but there was one “sharp, steep hill” just after crossing Pleasant Run. It wasn’t that long. From the creek, it topped out at what is now Bakemeyer Street. It is noted that if the rider wants to skip the bad road conditions and the hill, simply take the Madison Road south to a dirt road that connects between the two roads just south of the hill. That would be Yoke Street today, which is just south of the Concordia Cemetery. (It is still possible to travel this originally dirt road that became Yoke Street…but it requires darting through a parking lot between the Wheeler Mission Thrift Store and Planet Fitness [as of 30 September 2019].)

The next road encountered marks the line between Center and Perry Townships. This dirt road “goes east as far as the Churchman pike, crossing the Madison and Shelbyville roads. To the west, it crossed the Bluff road, and runs to the river a mile and a half away.” This road now has the name of Troy Avenue. The Churchman Pike is now Churchman Avenue, and connects at what it is now 17th Avenue and Albany Street in Beech Grove. Before that, it crosses the Madison Road (Madison Avenue) and Shelbyville Road (Carson Avenue).

One half mile south of the road mentioned above is a road that is in such bad shape, the newspaper recommends avoiding it, since it is rarely used. Today, that road can be found by St. Roch Catholic School on the southeast corner. It is now Sumner Avenue.

Before reaching Lick Creek, two dirt roads lead off to the west. The first again connects the Three Notch to the Bluff. Today, that is Hanna Avenue. “The rider is advised to beware the second road, however, as it wanders off into the country for a short distance and then fades from sight, getting tangled up in a farm yard.” The street sign at the Meridian Street end of this dead end road proclaims it as Edwards Avenue today.

At Lick Creek, it is noted, that the road is in excellent condition. There is also a “immense white barn, which, from its size and neat appearance, is an attractive feature of the landscape.” The next reference is something that needs some research. I am not quite sure what the writer is talking about in the following passage. “A dirt road turns east three and three-quarter miles from the Belt and runs across the county, connecting with the Michigan Road. This is a delightful ride in the summer, but now the road is muddy.” One would think that it mentions what is now Thompson Road…and it does run most of the way to the Michigan Road at the time. But only from a point halfway between the Three Notch and the range survey line (now Shelby Street). That halfway point is now East Street, or US 31. Also, Thompson Road doesn’t make it all the way to Michigan Road (Southeastern Avenue). It does, however, connect (more or less) directly to the same town, Shelbyville, as the Michigan Road.

Indianapolis News, 10 April 1896. Part of a map of the entirety of Marion County included on page 9 of that issue of the newspaper. This snippet shows that area from the Three Notch Road east to the Michigan Road as it existed at the time. Most of the highlighted road is now called Thompson Road.

The Three Notch Road after this dirt road, according to the News, turns slightly to the southwest. This would make the dirt road Thompson, but the mileage doesn’t match, nor does the map snippet above.

The next puzzle in the article is that it mentions two cemeteries that the old road passed after the slight southwesterly turn, “but only for a short distance. It climbs and winds round a hill on which is situated a small burying ground, the chief feature of which is a large stone vault facing north. It can be seen for miles. The road swings around the hill and down the other side. Just back of this hill, on the east, is another cemetery.” At the corner of Meridian Street and Epler Avenue is Round Hill Cemetery. There is mention of a small church in the area, “in a grove of trees to the east of the pike.” Here, a dirt road again connects to the Madison and Bluff Roads, then getting lost in the White River bottoms west of the Bluff Road. This would be Epler Avenue today.

Less than half a mile later, another longer dirt road crossed the Three Notch Pike. This road connects the Bluff Road to the west to the Michigan Road on the east. This road is right about the same spot that Little Buck Creek is crossed, making the road the current Edgewood Avenue.

The last point mentioned in the article is the location of Webb Post Office, located at the Southport Pike, seven miles south of Monument Circle. From this point, the rider can choose to cross over to the Madison Road (and the town of Southport) for travel back to the city, or continue the 30 miles south to Brown County. Riding the Southport Pike requires crossing Little Buck Creek “four times inside half a mile.”

From here, the Three Notch Road continues through Johnson and Morgan Counties before reaching Brown County. The old road, which became SR 35 (later SR 135), is mentioned here and here.

US Highways: They are actually State Roads

I originally posted the following in the Indiana Transportation History group on 11 Jun 2014. It has been slightly edited to correct some “oopsies” in my original.

For those old enough to remember (and I, unfortunately, am not one of them) before the Interstate system came into being, and US routes were the cross-country method of auto transport, this post is for you.

Somewhere lost in the history of transportation is the true story behind the US Highway system. Believe it or not, the Federal Government was late to the “good roads” party, and really only joined it half-heartedly. Let me explain.

Near the end of the 19th Century, there was a craze sweeping the nation – bicycling. The problem was that most roads at the time were basically dirt paths through the country. Some were graveled, yes. Some were bricked, but mainly only in towns. Those that rode bicycles started clamoring for better roads to reliably and safely use their new-fangled transportation method.

The US Post Office was also involved in this movement, mainly because mail was that important. And delivering the mail in some rural locations was troublesome at best.

With the creation of the automobile boom in the early 20th century, the Good Roads Movement started including the drivers of the horseless carriage. Again, because most roads at the time were dusty at best, and practically impassible at worst.

Clubs started nationwide to encourage auto travel (the Hoosier Motor Club was one). Clubs were also started to encourage the creation of travel routes that were more than dirt roads to the next county seat.

These last clubs led to many named highways throughout the nation. For instance, Indianapolis was served by the (Andrew) Jackson Highway, Dixie Highway, Pikes Peak Ocean-to-Ocean Highway, National Old Trails Road, the Hoosier Highway, Michigan Road, the Range Line Road, the Hills & Lakes Trail, and the Hoosier Dixie.

The most famous of the Road Clubs was the Lincoln Highway Association, which crossed Indiana through the northern tier of counties. On its trip from New York to San Francisco, it passed through Fort Wayne, Ligonier (included because it was the SECOND Ligonier on the route – the other being in Pennsylvania!), Goshen, Elkhart, South Bend, La Porte, and Valparaiso. (As you can guess, it wasn’t exactly a straight line at first!)

In 1926, the American Association of State Highway Officials (AASHO), in cooperation with the Department of Agriculture’s Bureau of Public Roads finalized a national route system that became the US Highways. This was to combat the numerous named highways that led to some major confusion among the automobile traveling public. The system was discussed starting in 1924, with a preliminary list issued in late 1925.

Named highways painted markers on utility poles most of the time. It, apparently, was not unheard of to have numerous colored markers on one pole. And new named highways were popping up monthly. (They even kept appearing after the numbered highways started appearing.)

A misconception is that a US Highway is a Federal road. US Highways have a distinctive shield with a number. It can also have, legally, a State Road marker. That’s because US highways were really just state roads that shared the same number for its entire distance. So SR 40 in Indiana was also SR 40 in Illinois and Ohio, and so on. (INDOT has even posted SR 421 signage on SR 9 at the entrance ramps to I-74/US 421 in Shelbyville.)

While US highway numbers have come and gone across the state, most of them appeared in one of two phases – 1927 and 1951.

The original US Highways in Indiana were: 12, 20, 24, 27, 30, 31, 31E, 31W, 36, 40, 41, 50, 52, 112, and 150.

The second major phase included US 136, US 231, and US 421.

Between these two phases, the following roads were added:
– US 6 (1928)
– US 33 (1937)
– US 35 (1934) It required changing SR 35 to SR 135.
– US 36 – Yes, it is listed twice. US 36 originally ended at Indianapolis from the west. It was extended east in 1931.
– US 152 – Mostly followed US 52 (Lafayette Road) north from Indianapolis from 1934 to 1938. It never left the state, so it was downgraded to mostly state road 53 (which, strangely, was added BACK into the federal numbering system as US 231).
– US 224 (1933)
– US 460 (1947-1977)

These were added to the system in sections. For instance, US 6 came into Indiana from the east and ended up being routed along what, at the time, was Indiana State Road 6.

There have been many changes in the original US highways. Some have bypassed towns in many places (like US 31). Some have just been removed from the system (like the northern end of US 33). Some were replaced by the interstate system created in 1956 (like US 27 north of Fort Wayne).

The beginning of the end of the major importance of the US Highway system started in 1947, when AASHO deemed it “outmoded.” This led to the creation of the interstate system with a law signed by President Eisenhower in 1956.