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

1952: Another New US Highway

Between 1951 and 1952, there were a lot of highways that were added to the US Highway system by the AASHO, or American Association of State Highway Officials. The main reason for this was, quite honestly, “tourist roads.” That was the purpose of expanding US 421, mentioned in my last post, from Tennessee to Michigan City. Another addition was US 231, which crosses the state from Owensboro, Kentucky, to Lake County, Indiana.

At the time, the two major US Highways that crossed Indiana, US 31 and US 41, were very busy doing what they do best – moving travelers north and south. Both highways start in northern Michigan, with US 41 beginning in the Upper Peninsula, US 31 starting at Mackinaw City. At the other end, US 31 ends in southern Alabama, US 41 end at Miami. Both highways were essentially “tourist roads.”

Since US 41 connected Chicago and Miami, it was the US highway replacement for the Dixie Highway. And as such, was very busy. AASHO decided that it would be a good idea to create another south bound highway to funnel off traffic from the two major roads crossing Indiana. That road would be US 231.

The Lizton Daily Citizen of 17 September 1952 mentions that the new route markers for the newest US highway in Indiana were in stock and to be replaced over the next month or so. It was also mentioned that the state road numbers that were assigned to route that would become US 231 would still be there after the marking of the US route. “The newly-designated U. S. 231 will travel from Chicago, Ill. to Panama City, Fla. It is to be called a ‘tourist’ highway and is designed to relieve overloaded U. S. 41 of some of its traffic.”

US 231 started life in 1926 with the creation of the US Highway system. At the start, it began at US 90 near Marianna, Florida. Its northern end was at Montgomery, Alabama. The first expansion of the road had it ending in Panama City, Florida.

US 231 crossed into Indiana from Owensboro, Kentucky, on what was then SR 75 (now it is SR 161), then east on SR 66 to Rockport. From there, it would follow SR 45 to near Scotland, SR 157 to Bloomfield, west on SR 54 to SR 57, then north on SR 57 to its junction at SR 67.

From the junction of SR 57 and 67, the new highway would follow SR 67 into Spencer, where it would be joined with SR 43. From here, it would follow (replace) SR 43 north from Spencer to Lafayette.

Now, here is where the description of the highway in the newspaper and the actual route differ. According to the route published in the newspaper, the route would follow SR 43 all the way to Michigan City, ending there. Well, it was already mentioned that it would end in Chicago (which, by the way, it never did), not Michigan City. Also, again, as mentioned in my last blog entry, US 421 took SR 43 into Michigan City.

At Lafayette, US 231 would multiplex with US 52 to Montmorenci, where it would turn north on SR 53. Now, for those of you keeping score with the US highways in the Hoosier state, this is where, from 1934 to 1938, there was another US highway that had been removed for being too much of a duplicate. That highway, US 152, used the US 52 route from Indianapolis to Montmorenci, where it replaced SR 53 (which it was in 1933) all the way to Crown Point. In 1938, with the decommissioning of US 152, the road reverted to SR 53 again.

And in 1952, that designation was once again removed for the placement of US highway markers. This time, US 231. But, the state road number wasn’t removed immediately this time. And US 231 rolled its way along SR 53 until it entered Crown Point. From there, it connected to US 41, the road it was supposed to help relieve traffic, near St. John using what was then SR 8.

For the most part, with the major exception of two places, the US 231 route is the same as it was back then. There may have been some slight moving of the road, especially near Scotland for Interstate 69, but the minor revisions are few and far between. The major relocations are definitely major. A complete reroute in the Lafayette area, which has US 231 bypassing both Lafayette and West Lafayette. It has, in recent years, taken to carrying US 52 around the west side of the area, replacing the much celebrated US 52 bypass along Sagamore Parkway. I will be covering that bypass at a later date. Let’s just say that there was a lot of newspaper coverage of that at the time.

The other major change in the route is near the Ohio River. A new bridge spanning the river was opened in 2002. The new bridge, called the William H. Natcher, is located north of Rockport. The original US 231 route, which followed SR 66 to due north of Owensboro, Kentucky, is now SR 161 between SR 66 and the Ohio River. It should also be noted here that at Patronville, SR 75 (US 231 now SR 161) had a junction with SR 45…the route that the new US highway would follow from northeast of Rockport to Scotland. Now that junction is just with Old State Road 45.

Due to its route across the state, at 297 miles long, US 231 is the longest continuous road in the entire Hoosier State. That may seem wrong, but consider that Rockport is actually south of Evansville…and the route through the state is nowhere near straight.

Indianapolis and the Original ISHC State Road System

I have posted much about the creation of the Indiana State Highway Commission. As of the posting of this article, the age of the Commission is either 103 or 101 years old. The original ISHC was established in 1917…but met with a lot of problems. It was finally nailed down in 1919 and made permanent.

This also creates a dating problem when it comes to the state highways. The first five state highways, then known as Main Market Roads, were established in 1917 with the original ISHC. Two of those original Main Market Highways connected to Indianapolis. The original National Road had been given the number Main Market Road 3. The Range Line Road, connecting Indianapolis to Peru, and through further connections, to South Bend, was given the Main Market Road 1 label.

When it was finally established, the ISHC changed the name of the Main Market Road to State Road, in keeping with other states surrounding Indiana. The markers used along the roads, painted onto utility poles like the old Auto Trail markers were, resembled the image to the left…the state shape with the words “STATE ROAD” and the route number. In this case, as of 1920, State Road 2 was the original route of the Lincoln Highway through northern Indiana.

The state highway system was designed to, eventually, connect every county seat and town of over 5,000 population, to each other. Indianapolis, as the state capital and the largest city in the state, would have connections aiming in every direction. Most of those roads marked with the original numbers would still be state roads into the 1970s and early 1980s, before the Indiana Department of Highways started removing state roads inside the Interstate 465 loop…and INDOT finishing the job on 1 July 1999. These road were removed for state statutory limitation reasons, and I have discussed that in a previous blog entry. So I won’t do it here.

The original state road numbers that came to Indiana varied greatly, as did their directions. There were no set rules when it came to state road numbers. They were assigned as they came…and stayed that way until the first renumbering of 1923, or the Great Renumbering of 1926.

Let’s look at the original state roads in Marion County, some of which actually did not reach Indianapolis itself.

State Road 1: As mentioned before, State Road 1 was originally called Main Market Highway 1. North of Indianapolis, it followed the Range Line Road, a local Auto Trail, through Carmel, Westfield, to Kokomo and points north. The route north followed Meridian Street north to Westfield Boulevard, then Westfield Boulevard on out to Carmel and beyond. In Carmel, the old road is still called Range Line Road, and serves as the main north-south drag through the town, as it does in Westfield.

South of Indianapolis, State Road 1, like its Main Market Highway predecessor, followed the old Madison State Road out of the city to Southport, Greenwood, Franklin and Columbus. The original SR 1 route is still able to be driven through the south side of Indianapolis, with the exception of the section replaced in the 1950s by the Madison Avenue Expressway. But Old Madison Avenue exists, if you can find your way back there.

While the entirety of original State Road 1 became US 31 with the Great Renumbering, bypasses in Marion County were put in place very early. The northern section, through Broad Ripple, and Carmel was replaced as early as 1930. The southern section, including the Southport/Greenwood bypass, was put in place in the 1940s.

State Road 3: As mentioned above, Main Market Highway/State Road 3 followed the National Road through Marion County. One exception to this is the section of the 1830s National Road that crossed the White River downtown. That section of the old road was removed in 1904 with the demolition of the National Road covered bridge and its replacement with a new, and short lived, Washington Street bridge. With a couple of exceptions other than that (the Bridgeport straightening of the early 1930s, and the new Eagle Creek bridge built in the late 1930s), the old road was followed very accurately until the mid-1980s with the creation of White River State Park. The successor to original SR 3, US 40, was moved to make room for the park. Both US 40 and US 31 lost their designations on 1 July 1999 with the removal of those two routes inside the I-465 loop.

State Road 6: This old state road was a through route when it came to Marion County. From the north, it followed the route of the original Indianapolis-Lafayette State Road from Lebanon. After passing through downtown Indianapolis, it left the county using the original Michigan Road on its way to Shelbyville and Greensburg. The original State Road 6 followed the Michigan Road Auto Trail, not the Historic Michigan Road, meaning it still went to Madison, but it went by way of Versailles, which the historic road did not. With the Great Renumbering, the northern SR 6 became US 52, while the southern SR 6 became SR 29 – later to be renumbered again to US 421.

State Road 22: This road, as it was originally laid out, only lasted from 1920 to 1923. Out of Indianapolis, it followed the old Mooresville State Road through southwestern Marion County. It was designated the original route from Indianapolis to Martinsville, as described in this blog entry. This road will be discussed again a few paragraphs from now.

State Road 39: Another 1830s state road that was taken into the Indiana State Highway Commission’s custody in 1919. This road followed the old Brookville State Road from the National Road out of the county through New Palestine to Rushville and Brookville. The original end of that road, both the 1830s original and the 1919 state highway, is discussed here. The road would become, in October 1926, the other section of US 52 through Indianapolis. It would also eventually become the first state highway removed inside the I-465 loop in Marion County. And even then, it would be rerouted in the late 1990s to go the other way around the county.

That covers the 1919 highways. More would come to Marion County before 1923.

State Road 12: Originally, this road, north of Martinsville, was the old State Road 22 mentioned above. When a new SR 22 was created, the SR 12 number was continued from Martinsville to Indianapolis along the old Vincennes and Mooresville State Roads. This road, in October 1926, would become part of the new State Road 67.

State Road 15: While the southern route of the Michigan Road was State Road 6, the northern part, heading off to Logansport, was added later and given the number State Road 15. The entire route of the historic Michigan Road would never become a state highway, but major sections did…although late in the creation of the state highway system. With the Great Renumbering, this road became SR 29, and in 1951, redesignated, like its southern half, US 421.

State Road 22: Here we go again. State Road 22 was given to the route between Indianapolis and Paoli. In 1919, that included the route along the west bank of the White River from Martinsville to Indianapolis along the Mooresville Road. This was changed by 1923 to keep SR 22 on the east side of White River, where it followed the old Paoli State Road, and the Bluff Road, through Waverly to the south edge of downtown Indianapolis at Meridian and South Streets. This was one of the routes of the Dixie Highway through Indianapolis, and would later become part of SR 37 in 1926.

State Road 31: In 1920, when this road was originally created, it turned south to connect to the National Road west of Plainfield. It had followed the Rockville Road from Montezuma to Danville, then turned southeasterly to meet State Road 3. By 1923, the road was moved from what would later become part of what is now SR 39 to continuing on the Rockville Road into Marion County. State Road 31 would meet the National Road outside the city limits of Indianapolis at what is now the intersection of Holt Road and Washington Street. It would become US 36 before it was extended along the new section of what is now Rockville Road to the intersection at Eagle Creek with Washington Street.

State Road 37: One of two state road numbers that still served Indianapolis after the road numbers were changed in October 1926 (the other being State Road 31). The original State Road 37 left Marion County in a northeasterly direction on its way to Pendleton, Anderson and Muncie. Inside the city limits, the street name was Massachusetts Avenue. When it reached the city limits, the name of the road changed to Pendleton Pike. This still occurs today, with the name change at the old city limits at 38th Street. In October 1926, the number of this road would change to State Road 67.

There were two other major state roads in Marion County, but they weren’t part of the state highway system until after the Great Renumbering. One was the Crawfordsville State Road, part of the original Dixie Highway, connecting Indianapolis to Crawfordsville via Speedway, Clermont, Brownsburg, and half a dozen other towns. It would be added to the state highway system by 1929 as State Road 34. The number would change later to US 136.

The other road was the original Fort Wayne State Road, also known as the Noblesville State Road, but even more commonly called the Allisonville Road. It would be added to the state highway system in 1932 as State Road 13. Less than a decade later, its number would be changed to the more familiar State Road 37.

State Roads, 1831 (Part 2)

This is a continuation of yesterday’s entry: State Roads, 1831 (Part 1). Remember: The concept of “state road” was completely different that it is today. Today, a state road is a road that has become the responsibility of the state transportation authority (for instance, now INDOT). Then a state road was a road that was authorized by the state, paid for by the state, but built and maintained by the county through which the road passed. So, basically, the state using Federal land proceeds to pay for, what will be, county roads. Some of these routes DID cross the line between the two different types of state roads.

Section 7: The section first listed in this act, from Frankford (Frankfort) to Delphi roughly follows US 421. The route to connect to the road that was mentioned in Section 6 of the same chapter, this road could have basically used a (more or less) straight line that follows SR 18 from downtown Delphi to SR 43. Or, followed what is now US 421 from Delphi to Michigan City. I am leaning toward the former.

Sections 8, 9 and 10: These sections talk about the Commissioners: their oaths, duties, paperwork to be done, and payment for service. Other things discussed was the fact that although the state is paying to make the road, it is the county’s responsibility to open and maintain them. The minimum requirement for the road to be open is that it be no more than 40 feet wide.

The three percent fund is the money that the Federal Government gave the state after the sales of Federal land. The state was given three percent of the sale price.

Section 11: Of the several places mentioned in this section, one (Baltimore) disappeared when the Wabash & Erie Canal was built on the opposite bank of the Wabash River, and another (Legrange) is very hard to find out any information. There is one old brick house left of Baltimore. It is located on SR 263 at Warren CR 1025S. (Strangely, Google Maps has SR 263 labeled “Old State Highway 63” as the street name.) The road starts at the Warren County line as Warren CR 600W. The original road has disappeared between US 136 and the old location of Baltimore.

Section 12: This is one of those “special acts” that I mentioned in my Indiana Toll Road(s) post on 24 May 2019. The state road starts at one person’s farm? Really? Exactly where IS Walker’s Farm in Parke County? At least from Clinton to Newport, the road roughly resembles SR 63 (or, at least, old SR 63).

The Acts of 1830, available here, shows more state road laws put into place that year. I will be covering those at a later date.

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.