Minnesota/Minnesota highway classification

From OpenStreetMap Wiki
Jump to navigation Jump to search

This is the project page for the State of Minnesota highway classification project. This page and its sub pages contain the current status, inventories, proposals, and implementation tracking for major highways in Minnesota.

If you are new to this wiki page, please look it over. If you are familiar with the current content and want to help the effort by joining the discussion or changing the map, please go to the last section of this wiki page titled Call to action.

Introduction

This project is a state specific classification project that builds on the United States highway classification project. Reading that information is encouraged as it is the foundation for the work being done in Minnesota. It is also useful to refer to some of the other states' efforts which are linked to by that page. Many of the other state projects use good practices that can be used to inform our approach. Note also that there is an active community of Minnesota mappers who are using Slack to discuss this work. Refer to the #local-minnesota Slack channel.

Purpose

This page is a place to organize the classification of Minnesota highways to align with a more contemporary view of highway classifications. The goal is to start at the higher levels first by selecting the highways that are physically motorways and also the trunk highways that connect regional centers and then eventually work to provide a set of rules to classify other highways in the system at lower priorities. This work is inspired by and will consider broader US Highway Classification work being done.

Current status

This chart summarizes the current overall status of this project based on highway type. This chart will be updated as progress is made.

Summary Status of Minnesota Highway Classification Project
Highway type Inventory Proposal Implementation
Motorway Completed Proposal (version 2) has been agreed; wiki page (this) has been updated to reflect the agreed guidelines. In progress
Expressway Completed A proposal of September 2022 to conform to the then-current US guidelines has been agreed; wiki page (this) has been updated to reflect the agreed guidelines. In progress
Trunk Completed Proposal (version 4) has been agreed; wiki page (this) has been updated to reflect agreed trunk network In progress
Primary
Other types Not within scope of project at this time

Process

The US highway classification project suggests a process to use for a project like this. Before doing any changes to the map based on this, please refer to the Process to follow section below which summarizes that guidance and provides Minnesota specific information. Like anything else in this wiki and on this project, discussion and changes are encouraged.

Scope

The classification of motorways and trunk highways in Minnesota has been actively discussed as have the identification of regional centers and metropolitan areas such as the Twin Cities metro area. This discussion may be expanded to include primary highways (TBD). Whether to expand this effort to other highway types has not been decided at this time.

Out of scope

There are many things that can be mapped in OSM that are not in the scope of this project. Items excluded from this project are buildings, water, land use, bridges, paths, trails, crosswalks etc. Also currently out of scope are recommendations about road attributes such as pavement type, alignment, lanes, intersections, speed limits, etc. This is not an exhaustive list of the exclusions. The final section of this page gives possible future scope expansions. None of these have been discussed at this time.

Current inventory

This section includes inventories and analysis done early in this project to analyze the motorways and trunk highways in the state. The detailed inventory can be found at Minnesota/Minnesota highway classification/Highway inventory. Note that the material on that page used to live here but has been moved there to make this page more readable. This page now has a simple summary chart of the types of highways mapped in OSM in Minnesota.

Inventory summary of Minnesota highways by type and surface

In late December 2021 (24th & 25th) a survey of Minnesota highways by type was done using overpass turbo queries. The results are summarized below. It is anticipated that may be updated in the future to provide a progress report.

Lengths of highway by type/surface (Kilometers)
group highway surface December 2021
major motorway 4,330.6
trunk 4,106.6
primary 7,265.0
expressway=yes 19.4
major link motorway_link 1,504.7
trunk_link 171.8
primary_link 59.7
mid secondary 14,034.5
tertiary 56,882.1
mid link secondary_link 71.9
tertiary_link 48.3
minor unclassified 14,023.8
residential * 22,394.7
residential gravel 12,720.2
residential asphalt 5,135.2
residential unpaved 3,130.7
residential paved 1,252.3
residential concrete 52.9
residential dirt 61.0
residential other 42.4

Notes

  1. blank surface means that the surface type was not specified in the query
  2. expressway=yes is not a highway type, but rather an attribute of some highway segments (usually trunk)
  3. all residential roads probably exceed 100,000 km (query would not complete)
  4. residential with surface=* includes all residential roads that have a surface tag
  5. residential with surface=other is not a query but rather derived arithmetically from the other residential queries
  6. based on notes 3 & 4 above, it is not possible to estimate the total length of residential roads nor the length of residential roads with no surface type

Regional centers

The cities important to the understanding the Minnesota motor vehicle transportation network for the purpose of classifying highways are partitioned into “tiers”. The lower number of the tier the more significant the need for connectivity with other cities. This proposal only deals with the perceived importance of the city. The "helper" key MN_city_tier with values 0-5 has been attached to the administrative boundary relation for each city. (A general discussion of this and other helper keys can be found at Helper keys.)

Twin Cities Area (Tier 0)

Other states (example New York) have considered it necessary to consider typing of roads and highways in major metropolitan areas differently than less populated (and less paved) areas. No decision has been made in Minnesota to do that, but if such a decision is made it was felt necessary to delimit the area deemed to be part of the “Twin Cities metropolitan area”. This term is used and defined here to describe the area where special consideration might be needed for classifying the highway network. It is not an official term that can be looked up somewhere else, but rather an artifice to be used in the classification effort.

Area selected and method used

The method used to demark the metropolitan area is to include all incorporated cities that are contiguous and either surround or include Minneapolis or St. Paul. This area has a well-defined boundary and within that boundary are very few unincorporated areas (the MSP airport is one example). Note that this method includes two Wisconsin cities.

An OSM "helper" key (MN_metro=TC) has been developed that is used to mark the “edge cities” of the metropolitan area. The key is used on each city that is both within the area and next to an area that is not. The area is shown below based on an overpass turbo query. The selection criteria in the query were chosen to show both the edge cities and Minneapolis and St. Paul.

TC metro area.jpg


The following shows a raw overpass turbo query showing both the metropolitan area and all the OSM motorways and trunk highways (as currently tagged).

TC metro area with motorways and trunks.jpg

Other alternatives considered

Several other options were mentioned in our Slack discussion but not adopted. In general, these areas seemed much larger than needed to encapsulate the area needing possible special attention. Discussed but not adopted are:

  1. An eight-county area used for Minnesota highway planning (that area can be seen in the overpass turbo query for MN_metro=TC_county.
  2. A seven-county area used for metropolitan area planning (the Met Council)
  3. A six-county area (subset of the above)
  4. A five-county area (a further subset)
  5. A Twin Cities & St. Cloud statistical area (includes another possible metropolitan area: St. Cloud)
  6. A census statistical area including Sherburne, Chisago and Isanti counties

Tier 1 Cities

Tier 2 Cities

Tier 2 Cities.png

Tier 3 Cities

Tier 3 Cities.png

Tier 4 Cities

Tier 4 Cities.png

Tier 5 Cities

Tier 5 Cities.png

Notes about the charts above

  1. The city name sometimes includes the named city and another nearby city or more. In one case it explicitly excludes another nearby city. Sometimes the additional city is in a nearby state.
  2. Cities with * (two of them) were not included in the original connectivity analysis. [This distinction will be removed in a subsequent update to these charts]
  3. Cities with ** (two of them) may be considered part of Tier 0 (the Twin Cities area). [This can be seen in the Tier 0 discussion about the metro Twin Cities above.]
  4. Any cities not named are deemed to be either part of the Twin Cities or considered to be less important than the ones named above
  5. The column MW+T is the number of Motorway and Trunk roads (as currently mapped in OSM) that enter or leave the city. A city with one Motorway going through the city would have MW+T=2. For this analysis, in several cases, the determination is made by zooming out a little from the city. So, for instance, a US Highway (trunk for this example) that bypasses the city to avoid disrupting the business district of the city would be counted as “touching” the city and would be MW+T=2.
  6. The column PR likewise counts the number of currently mapped Primary highways that enter or leave a city.
  7. Some cities can also be characterized by the fact that, while they are in Minnesota, they are “gateways” to important cities in nearby states or Canada. The Gateway Note identifies these cities. The fact that they are gateways factors into their final tier assessment.
  8. One city did not seem to achieve the importance it deserved (in the author’s view) based on the connectivity analysis alone. Hence the strange note of being a gateway to “fishing”. (The fact that the author has relatives from there did not affect this assessment!)

Proposals

This section contains the current proposals to highway classification in Minnesota. Items in this section are considered preliminary and open for review.

Agreed guidelines can be found in the next major section Agreed guidelines.

Previous proposals, analysis and discussion results can be found in the Archived Information section at the end of this wiki page.

To create a new proposal, create a new subsection with the name of the proposal and either include the proposed changes there (in this section), or provide a link to a new wiki page with the proposal details, or point to another document that has the proposal details

At this time there are no active proposals.

Agreed guidelines

This section contains guidelines that have been agreed by the participants of the classification discussion. This section serves two purposes: 1) to document the agreed guidelines; and, 2) to track progress as it is made against these guidelines. Before doing any OSM reclassification of highways be sure to read this section and the next section which details the process including the use of special hash tags and recommended changeset text.

Tagging general guidelines

Motorways

In general, Minnesota follows the US guidelines. Please review section 2.1 Motorway. The text here simply summarizes the general US guidance for motorways and does not provide any different guidance. The general guideline is that the highway is either a signed Interstate highway or it possesses a set of physical characteristics about grade separation, on/off ramps, at-grade intersections, divided carriageways, and that it is designed for high speed for long distances. That wiki (in section Exceptions and Borderline Cases) addresses how to address gaps in Interstate Highways. There are no such gaps in Minnesota.

Motorway islands

The US Exceptions section also defines and addresses how to handle "motorway islands". The US guidelines give the states some leeway in how to handle them. While it provides general guidance, it provides each state the ability to provide its own guidance provided there is discussion and consensus about the approach. Please review the US guidelines. Following are the agreed Minnesota specific guidelines.

If a section of highway appears to meet the US physical definition of a motorway and it is an "island", use the following guidelines to determine whether to categorize it as a motorway or trunk. (Note that while there may be instances of motorway islands that are parts of primary or lesser highways, none were encountered so far, so "trunk" is used here.)

General guidelines to follow for classifying possible motorway islands
1 If the candidate has three or more grade-separated interchanges it should be categorized as motorway motorway
2 If the candidate has two grade-separated interchanges it should be classified as motorway unless: motorway
a It is discussed in a forum such as Slack and the consensus is it should be a trunk (e.g. MN7a, MN13a, MN36b, MN51a) trunk
3 If the candidate has only a single grade-separated interchange, it should be classified as trunk unless: trunk
a It is actually part of (connected to) a larger motorway island (see for example: MN36a), or motorway
b In addition to the grade-separated interchange, it also has multiple bridges separating its traffic from other highways (e.g. US169i, MN65a, MN65b), or motorway
c It is discussed in a forum such as Slack and the consensus is it should be a motorway (e.g. MN15c) motorway

Where does the motorway island end? Consider each end of the island independently. For each end, as long as the other physical attributes apply, the end of the motorway island will be delimited by the first at grade intersection encountered. If the first at grade intersection for both sides of the divided highway is the same, then that is where the end should be marked. But what do you do if one carriageway has an intersection that is not shared by the other carriageway? If you applied the rule to each carriageway independently then one of motorway's carriageways would be longer than the other. The consensus in a discussion in the #highway-classification channel of slack seems to be that the longer one should be truncated to match the shorter one.

Example of where to end a motorway island.

The above example of the end of a motorway island (MN 36 East where it intersects with CR 15), as rendered by overpass turbo, shows the East bound and West bound carriageways ending at the same place (B). The mapper determined that the motorway "broke" at the driveway abutting the East bound carriageway and decided to end the West bound carriageway at the same "point". The West bound carriage way is not "broken" until point A, but the guidance proposed above says that point B is the correct place to end both sides of the dual carriageway highway (the motorway).

Motorway spurs

There is no clear guidance about "motorway spurs" in the US guidance other than the network of highway=motorway or highway=trunk roads "should collectively form a coherent network of interconnected roads without dangling spurs or 'islands' of disconnected roads." The following is how to handle motorway spurs in Minnesota.

A motorway spur meeting the US physical criteria that exists, or is created in the future, is acceptable in Minnesota if it connects to a motorway network. An example is a motorway leaving the Twin Cities metro area that peters out and becomes a trunk highway until it reaches some regional center. If the part of the highway "beyond" the motorway spur should be trunk and the spur meets the physical criteria of being a motorway, then it is appropriate to leave the motorway as mapped or, in the future, map it as a motorway if it meets the physical criteria of being one.

If there are motorway spurs that do not meet the above criteria (i.e. they do not morph into a trunk highway that connects to a regional center) then they should be discussed individually in the #local-minnesota Slack channel or the talk page as a possible exception to this overall guidance.

Where does a motorway spur end? Use the same guidance as for motorway islands.

Interstate non-motorways

In Minnesota, all Interstate highways (35, 35E, 35W, 535, 90, 94, 394, 494, 694) seem to be entirely mapped as motorways, although there are some gaps in the correct mapping and in one case very poorly mapped (I-535). So there are no cases of Interstates that are not motorways. But there are some Alternate or Business Interstate segments. They should be mapped correctly as for any other highway in the area. They may be trunk, primary, etc.

Expressways

The US Highway reclassification page has a section mostly devoted to expressways titled Exceptions and Borderline Cases. The guidance provided there seems to apply well in Minnesota. Note that as of December 2021 the expressway=yes tag has only been used on a single highway segment for a total in Minnesota of 19.4 kilometers.

Minnesota will follow the US Guidelines for expressways.

Minnesota will also follow the guidelines for using the expressway Key as documented in Key:expressway. For Minnesota it is assumed that the guidance given in both cited sources is sufficiently consistent. Minnesota mappers should refer to one or the other or both for clarification. The chart in the Key:expressway page in the section "How to Decide" might prove useful to mappers.

Refer to the specific route by route proposals listed below.

Trunk highways

As with the expressway consensus, Minnesota's trunk guidance tracks closely with US Highway reclassifcation guidance. Before this proposal was developed, highway=trunk was mostly used for high-speed routes with divided carriageways that did not classify as highway=motorway, as was true in much of the United States.

The agreed to consensus in Minnesota adopts the new view of highway=trunk that is most accepted in the United States today. That is, so long as they are reasonably well-built, highways are trunks if they connect population centers or regions. These trunks should form a network with motorways that is neither too dense nor too sparse.

Refer to the specific route by route proposals listed below.

Primary highways

Placeholder for presumed future guidelines about primary highways

Twin Cities metropolitan area

This section is used to provide guidance for the various highway types that are within the Twin Cities metropolitan area as described earlier. Refer to section Regional centers/Twin Cities Area (Tier 0).

Twin Cities metro area guidelines
Highway type Guidelines
Motorways Motorways in the metro area will follow the general guidance described above. They will not be treated specially in the Twin Cities metro.
Expressways Expressways in the metro area will follow the general guidance described above. They will not be treated specially in the Twin Cities metro
Trunk highways TBD
Primary highways Placeholder for future guidelines about primary highways in TC metro

Route by route guidelines

This section has the specific highway by highway guidelines. Also provided in each of the tables is a column to track progress. Refer to section 6 for process details.

Motorway detailed guidelines

This section provides details of what should be done for all highways in Minnesota that are either currently tagged highway=motorway or in the views of this project, should be. These details are based on the careful inventorying done in section 2.2 Motorways, above. For all of the highways listed below mappers should verify that the highway sections currently tagged as motorway actually meet the general guidelines given in section 4.1.1 Motorways. Consider for each section of each highway whether it ends in the right place. This includes especially considering the end points of motorway islands and motorway spurs. Additionally, any incorrect gaps should be fixed. A gap can be formed due to not tagging the segment with highway=motorway or not having the segment correctly part of a route relation for that highway. All highways named below should be carefully reviewed for all of these things. The table provides some indication based on the inventory for which highways are known to have islands, spurs or gaps. The inventory process may have missed something so it is important for mappers to carefully review the entire highway route.

The following chart provides a simple list of the motorways to be carefully mapped according to the guidelines. Notes follow to explain the columns in the table.

Class Highway Network Ref S I G SeeSpecial Progress
US I 35 US:I 35 G S2 done
I 35E 35E G done
I 35W 35W G done
I 535 535 S2
I 90 90 G done
I 94 94 S2 done
I 394 394 S2 done
I 494 494 G done
I 694 694 G done
US 2 US:US 2 S I G S1
US 8 8
US 10 10 S I G S1 S2 S3 done
US 12 12 S G done
US 14 14 S I G S1 S3 done
US 52 52 S I G S1 S3 done
US 53 53 I G S3
US 59 59
US 61 61 I
US 63 63 S S2
US 71 71 S2
US 169 169 S1 S3
US 212 212 S
US 169 Bus US:US:Business US 169 Business I
MN MN 5 US:MN 5 G
MN 7 7 I G S1 S3
MN 13 13 S3
MN 15 15 I S1 S3
MN 23 23 I S1
MN 30 30 I S1
MN 36 36 S I G S1 S3
MN 37 37 I
MN 47 47 S
MN 51 51 I G S3
MN 55 55 S I S1
MN 60 60 I
MN 62 62 S I G
MN 65 65 I S1
MN 77 77 S
MN 100 100
MN 101 101 I S1
MN 252 252 S2 done
MN 280 280 S
MN 371 371 S1 S3
MN 610 610 G
County CR 34 (Hennepin) US:MN:Hennepin 34
CR 21 (Scott) US:MN:Scott 21 S S2
CR 101 (Scott) 101 I

Notes

  1. Network is the network identifier used in the route relation for this highway
  2. Ref is the reference number used in the route relation. For example: network US:US ref 169 refers to US Highway 169
  3. S I G indicates whether this highway has a S(pur), I(sland), or G(ap) (some of the data in this column may be iffy)
  4. See Special means that one or more of the three "special" tables below are relevant to this highway. The special tables have captions Table S1 ..., Table S2 ..., and Table S3 ...
  5. The Progress column is explained in section 6.2 (Mapping steps and progress tracking) below.
Special concerns

The following charts detail some special concerns to be addressed for some of the highways listed above.

The chart below is a list of all the current motorway islands that have been agreed should remain classified as highway=motorway.

Table S1: Motorway islands
Highway Island ID Progress
US 2 US2a
US 10 US10b done
US10c done
US10d done
US 14 US14b done
US14c done
US14d done
US14e done
US 52 US52a done
US52b done
US52d done
US 169 US169a done
US169h
US169i
MN 7 7b
MN 15 MN1560 done
MN15b
MN15c
MN 23 MN23a
MN23b
MN 30 MN3060 done
MN 36 MN36a
MN36c
MN 55 MN55a
MN 65 MN65a
MN65b
MN 101 MN101a
MN 371 371a

The following chart identifies some other special concerns. Also included are two special areas of concern in Minneapolis and St. Paul.

Table S2: Additional motorway special concerns
Highway Concern Progress
I-35 I 35 has a number of issues in Duluth including apparent use of older aerial photos and gaps caused by not hooking correctly to I-35 route relations. done
I 35 does not connect to I 535 correctly (Duluth)
I-535 I 535 is not totally mapped (Duluth)
I-94 I 94: near Monticello, should the MnRoad Mainline bet tagged Motorway? On 8 March 2022 this seems mapped correctly. It is tagged as motorway. It is currently not part of the US:I 94 route relation, which seems OK. It only becomes "part" of I-94 when MnDOT opens it up for testing. done
I-394 I 394: where is W end? Based west end on signage visible east bound on the I-494 overpass. done
US-10 It seems like the connection from I-94 to US-10/US-61 should be motorway links, not motorways. Look carefully at this and decide one way or another. On 23 July 2022 this seems mapped correctly. The connection in question is part of US-10/US-61 so it is correctly a motorway, not a link. done
US 10 between the intersection with Ramsey Co 96 and I-35 W and also Ramsey Co Rd 10 between I-35 W and Ramsey Co Rd H has to be carefully classified. In some stretches motorway is used when it should be motorway link. In other parts expressay=yes seems more appropriate. This section was thoroughly reviewed and corrected on 23 July 2022. done
US-63 For a lot of US 63 in Rochester, while the road seems typed correctly, it is missing its US 63 relation
US-71 US 71 Business relation in has a ref=71 but should have a different ref to distinguish it from US 71 proper. See for example US 169 Business (US:US:Business, ref US 169 Business; US 71 Business in Wilmar should be a motorway link, not motorway. (May have to check with Slack #tagging or #highway-classification.
in Bemidji, the portion of US 71 near Bemidji looks correct but portions of the primary part of US 71 near the interchange with US 2 are not properly part of the US 71 relation
MN-252 MN 252, south segment; convert all motorway S from 65th Ave until it joins I-94 near the River (around 61st ave N). Convert to motorway link. This results in only I 694, I-94/US52 being motorways. All others are links. The only reason to go S from 65th is to link to those motorways or MN 100. done
MN 252, north segment: from 85th Ave N, convert motorway to link. The only reason to go N from 85th is to link to MN 610. This decision supported by Freeway Entrance sign just N of 85th. Also note there is a "252 Ends" sign not far from 85th (in order to establish end of 252 in route relation) done
Scott 21 CR 21 (Scott): from signalized intersection at County Road 18, there are several issues: not all segments are part of the CR 21 relation; there is an at-grade intersection at Hanen Avenue; it seems better to classify everything N of CR 18 intersection as motorway link instead of motorway. Except for the at grade intersection at Hansen, the only purpose of CR 21 is to link to other motorways.
Minneapolis in downtown Minneapolis, determine where the N end of Hiawatha Avenue is; then determine where the N end of its motorway segement should be. There is at least one issue: the ramp from S 8th St is motorway: should be link
St. Paul In downtown St Paul it seems like a thorough review should be made of the use of motorway vs motorway link. It looks like some of each may be wrong. It seems like all through carriageways of I-94, I 35E should be motorway, almost all others should be links.
How route concurrency might suggest an order of handling

There is often the overlapping of highway routes where two different routes use the same carriageways (for example in the north metro I-94, I-694 and US-52 are all co-located for a short stretch of highway). It makes some sense to fix the longest and/or "most senior" routes first. By accomplishing them, the lesser routes will often be easier to complete. A rough meaning of "most senior" is: Interstates, followed by US routes, followed by Minnesota highways, followed by county highways. The following chart tiers or groups routes in a possible order. Whether mapping is done in this order or not is not mandated. This is optional. It is just provided for consideration by mappers when implementing these guidelines.

Possible general order making changes
Tier Highway Progress Sub to Peer with
1st I 35 done
I 90 done
I 94 done US 52
US 52 done I 94
2nd I 35E done I 94, US 52 US 12
I 35W done I 94, US 52 US 12
I 494 done
I 694 done I 94, US 52 I 35E, US 10
US 10 done I 94, US 169 I 35E, I 35W
US 12 done I 94, US 52 I 35W
US 14 done I 90, US 52
3rd US 2 I 35
US 61 I 94, US 10, US 12
US 212 MN 5, MN 62
MN 5 I 494 US 212
MN 23 I 35
MN 55 I 94, US 52,I 35W MN 62
MN 60 US 14
MN 62 US 212, MN 55
MN 100
4th I 394 done US 12
US 59 I 94, US 52
US 63 US 52
US 71 US 2, MN 23
MN 30 MN 60
MN 36 I 35W
MN 47 US 10
5th I 535 US 53
US 53 I-535 MN-37
US 169 Bus CR-101
MN 37 US-53
CR 101 (Scott) US 169 Bus
6th US 8
MN 7
MN 15
MN 51
MN 65
MN 77
MN 101
MN 252 done
MN 280
MN 610
CR 34 (Hennepin)
CR 21 (Scott)

Notes

  1. Tiers are ordered from highest to lowest. Higher tiers could be done before lower tiers.
  2. Within tiers, highways are listed in the same order as in the first chart of all motorways.
  3. "Sub to" means that this highway is co-located with a highway in a higher tier. This information may prove useful.
  4. "Peer with" means this highway is co-located with a highway in the same tier. This information may prove useful.
  5. Blank cells indicate there is no co-location with other highways listed in this chart.

Expressway detailed guidelines

A highway segment currently (MN 60 between the Iowa border and Worthington) that is tagged with expressway=yes does not meet the criteria for being an expressway. Specifically there are numerous at grade intersections and there are no grade separated interchanges. The tagging should be removed. This step should be done prior to adding any new expressway tags. This tagging has been removed on 3/7/2022.

The following chart details specific places where expressway=yes should be used in Minnesota.

Note that this chart will be reviewed in detail and modified as required during the implementation phase of the September 2022 agreed proposal for using the expressway tag. The original table S3 was developed prior to this proposal and was developed based only on the motorway island analysis. It is expected that some of the details in this chart will be revised, including possibly adding expressway=no to some segments of some highways.

It is also expected that other changes will be made to this section during implementation where explanatory notes are required to describe specific situations. The reason for making changes to the chart and adding explanatory notes at all is to communicate more clearly to future mappers what specific changes (and rationale) were made to the map based on these guidelines.

Table S3: Expressways
Highway Island ID Progress
US 10 US10a done (see note below)
US 14 US14a done
US14a2 done
US 52 US52c done
US 53 US53a
US 169 US169b done
US169c done
US169d done
US169g
MN 7 MN7a
MN 13 MN13a
MN 15 MN153060 done
MN 36 MN36b
MN 51 MN51a
MN 371 371b
MN371c

Note: When implementing the agreed guidelines, it turned out the original analysis of US10a was incorrect. It is actually much longer and has many more intersections than originally noted. Almost all of this island is now deemed to be motorway. The ends have been properly mapped. One end has been typed a trunk/expressway, the other end just trunk.

Trunk highway detailed guidelines

After much discussion and a handul of proposals, the map at the top of this Slack thread depicts the consensus acheived on trunk highways in outstate Minnesota.

Below are listed the agreed to trunk corridors, generally listed from north to south and from east to west and their implementation status:

Trunks agreed to in outstate Minnesota
Road number(s) Route code (from proposal stage) North/east endpoint South/west endpoint Progress
MN 61 N/A Canadian border north of Grand Portage Duluth at I-35 done
MN 194 N/A I-35 in Duluth US 53 near Miller Hill Mall in Duluth done
US 53 14 Canadian border in International Falls I-35 in Duluth done
US 2 13a, 13b, 30a, 30b, 30b2 I-35 in Duluth North Dakota border in East Grand Forks done
MN 33 N/A Intersection with US 53 I-35 in Cloquet done
US 169 11, 12, 13c, E US 53 in Virginia US 14 in Mankato done
MN 210 16a, 16b, 22 I-35 south of Cloquet US 10 in Motley done
MN 371 18 US 2 in Cass Lake US 10 in Little Falls done
US 71 15 Canadian border in International Falls US 2 in Bemidji done
MN 11 26b, 26c, US 71 in International Falls MN 32 in Greenbush done
MN 32 26a MN 11 in Greenbush US 59 in Thief River Falls done
US 59 7b, 7c, 7d, 7e, 26a MN 32 in Thief River Falls MN 23 in Granite Falls done
MN 210 17 I-94 near Fergus Falls North Dakota border in Breckinridge done
ND 210 17 Minnesota border in Wahpeton ND 13 in Wahpeton done
ND 13 17 ND 210 in Wahpeton I-29 in North Dakota done
MN 336 N/A US 10 near Dilworth I-94 near Dilworth done
US 10 B, 21a US 63 near Ellsworth, WI MN 336 near Dilworth done
MN 23 5a, 5b, 5c, 5d, 5e, 5f1, 6a, 6b, 6c, 29b, 29c I-35 near Hinckley I-90 near South Dakota border done
US 8 20 US 53 in Cameron, WI I-35 in Forest Lake done
MN 65 N/A MN 23 in Mora I-694 in Fridley done
MN 15 4a, 4b, 31a, 31b, 32b, 32c US 10 in Sartell I-90 near Fairmont done
Stearns CR 75 29a MN 15 in Saint Cloud I-94 near Collegeville done
US 63 9.3, 9.4, 9.5, 23c US 8 in Turtle Lake US 61 in Red Wing done
WI 64 23 US 63 east of New Richmond Minnesota border near Stillwater done
MN 36 23 All done
WI 35 21b I-94 in Hudson, WI WI 65 in River Falls, WI done
WI 65 21b WI 35 in River Falls, WI US 63 in Ellsworth, WI done
US 12 2a, 2b, 2c, 2d I-694 in Minnetonka I-29 in South Dakota done
US 212 27b, 27c, 27d I-494 in Eden Prairie MN 23 in Granite Falls done
US 61 N/A I-494 in Newport I-90 in Dakota done
US 52 19 I-494 in Inver Grove Heights Iowa border south of Canton done
US 63 8 US 52 in Rochester Charles City, IA done
Dakota CR 47 9.1 US 52 in Hampton MN 3 in Waterford done
MN 3 9b Dakota CR 47 in Waterford I-35 BUS in Faribault done
I-35 BUS 9b MN 3 in Faribault I-35 in Faribault done
US 14 1a, 1b US 52 in Rochester I-29 in Brookings, SD done
MN 60 A US 14 in Mankato Iowa border south of Worthington done

Note: sections that meet motorway guidelines as layed out elsewhere in this wiki should be marked as such. All Interstates are motorways.

Primary highway detailed guidelines

placeholder for future

Process to follow

This section has two parts: the overall process to be followed by the states in their highway classification effort and some guidance specific to Minnesota on how to actually make map changes.

Overall process

The US 2021 highway classification guidance describes a recommended process to be followed by the states. The following table summarizes the approach recommended and an easy to refer to status of the entire project.

As we expect to do this project in phases, some of these steps will be repeated. New charts may be developed below for new phases of the project. For the first phase the emphasis is on Motorways and Trunk highways.

Minnesota Motorways, Expressways, and Trunk Highways
Step Step description Notes Status
1 Read and digest US approach Done
2 Draft specific guidelines This wiki page is the repository of Minnesota guidelines Ongoing
Specific guidelines for trunk highways were drafted and revised several times. Done
Specific guidelines for motorways were drafted and revised several times. Done
Specific guidelines for expressways were drafted and revised several times. Done
Develop a primary highway proposal
3a Contact other local mappers A number of local mappers have been invited to the discussion both in Slack and via direct messages in OSM. Done
3b Achieve consensus A trunk highway proposal was circulated for comment Consensus achieved
A motorway proposal was circulated for comment Consensus achieved
An expressay proposal was circulated for comment Consensus achieved
Achieve consensus for a a primary highway proposal
4 Achieve buy-in and update guidelines Agree general guidelines and revise wiki. Wiki updated
Agree trunk highway guidelines and revise wiki. Wiki updated
Agree motorway guidelines and revise wiki. Wiki updated
Agree expressway guidelines and revise wiki. Wiki updated
Agree primary highway guidelines and revise wiki
5 Re-tag highways per guidelines See some notes below about the re-tagging process See Mapping steps and progress tracking section below; Re-tagging for motorways and expressways and trunk highways has begun

For communications and consensus building the primary mechanisms are this wiki and its discussion page as well as the Slack #minnesota-local channel.

Mapping steps and progress tracking

This section provides a suggested approach to making changes based on the agreed guidelines.

While anyone can update anything in Minnesota in any order based on these guidelines, it is suggested that mappers communicate in Slack (if possible) about their intents and progress. This will help avoid two mappers updating the same highway at the same time. Alternatively to using Slack you may update this wiki page with status information.

Each of the tables for motorways, expressways and trunk highways have a tracking column (called Progress) which will be updated periodically by a wiki editor with these statuses:

  • blank (i.e. not started);
  • in progress (i.e. started but not finished);
  • done (i.e. this highway is done).

Any line in the tables that is not marked done is a candidate for work. The main motorway table refers to three special tables (S1, S2, S3). It is recommended that as each highway is being worked on that the three special table entries for that highway also be handled.

For all work done for this re-classification project the following changeset comment is suggested:

Implementation of agreed Minnesota highway classification changes.  https://wiki.openstreetmap.org/wiki/Minnesota/Minnesota_highway_classification #us-highway-classification #mn-highway-classification

The above will notify other mappers of the guidelines being followed and provide some hash tags that might be trackable to measure progress US wide.

It is important to carefully map the entire highway (e.g. the motorway or expressway segments) as there are often gaps. These gaps may be because the individual part is not tagged correctly or that it is not properly part of a highway route relation. Even most of the Interstates in Minnesota have gaps!

The US classification page recommends using expressway=yes under certain conditions and ensuring highway=trunk and highway=trunk_link roads (whether existing or newly classified) address whether or not bicycle and foot traffic are allowed. In Minnesota bicycles and pedestrians are allowed on any road not otherwise posted, so in general bicycle=yes and foot=yes tags should be used.

The US page gives some tips on using JOSM to do the updating and gives some ideas about useful Overpass Turbo queries (in support of JOSM -- not sure if they work with ID). It also provides a possibly useful query to validate what you have done.

Remember that there are Minnesota specific "helper keys" (see very next section) that might be useful for some of your editing.

Do not remove any MN_Mway_island keys at this time.

Helper keys

A potentially useful set of OSM keys is under development that may help in our inventorying, analysis, proposal writing, discussion and updating. A Helper keys wiki page has been developed to provide the bigger picture about the keys and summary descriptions of each with images to show how the keys could be used. Use of the keys by any mapper is not required. They are provided to help if they prove useful or ignored if they do not.

Potential scope expansions

 The following are not within scope at this time. The overall guideline might be to follow the normal tagging guidance for this (point to US, or point to the generic wiki pages?) highway=primary, secondary, tertiary, unclassified, residential, service roads (including driveways and parking aisles), tracks
possibly include additional metro areas (e.g. St Cloud, Duluth, ROchester)
Consider how to handle "special highways" such as Great River Road, Memorial highways
scenic roads (Minnesota and national -- https://en.wikipedia.org/wiki/National_Scenic_Byway)
see how New York and Vermont deal with naming issues (names, refs, syntax to use...). We may want to do the same thing here.
Minnesota Legislative & Constitutional Routes? (see plain text below this "banner") 

text from the previous version of this wiki about them follows

  • In the state of Minnesota a number of constitutional and legislative routes were created that are enshrined in the Minnesota Constitution and in law. No decision has been made how to treat these routes in OpenStreetMap. There is some current practice in Minnesota that will eventually be discussed and documented here. For more information refer to the Wikipedia article.

this from a Slack discussion in American-map-style on 1/15/2022:

  • If there are no actual shields on the road (which will require us to do some serious mapping), then the suggestion is to change the relation ref=* to unsigned_ref=*

Call to action

This section provides a current list of ways community members can contribute to the Minnesota highway classification effort. This list is expected to change frequently as progress is made or stumbling blocks are encountered. Please feel free to add to this list. All items in this list should be things that can be worked on right now as opposed to future work.

Read, Write, Review

These items are about the wiki and the proposals. They include advancing the community understanding of what needs to be done in Minnesota in the short term. The unordered short list follows:

  • If you have not reviewed the entirety of this wiki, a good first step is to look it over. It is the most detailed description of what we have done so far and what is left to do.
  • If you are not now participating in Slack, consider joining the Slack #local-minnesota channel. It has the most current and active discussion this author knows of dealing comprehensively with mapping topics in Minnesota including highway reclassification. It also has other focused discussion channels on a whole range of US mapping topics.
  • If you are aware of any other active discussions about highway tagging that would be relevant to Minnesota, please let us know (you can add pointers right here!)
  • Reach out to other mappers you know that are actively mapping motorways or trunk highways in Minnesota. Let them know about this wiki and also Slack if they are so inclined.
  • Resolve the question raised by Ian about US 61 as it leaves I-90 to head north along the river. Has its own thread in Slack 1/28/2022.

Change the OSM Map

The motorways, expressways and trunk highways guidelines have been agreed and mappers may begin making changes based on the guidelines. Please also refer to section 6.2 which provides some minimal process steps to ensure that mapping is done in an orderly fashion and that other mappers can be notified that the changes conform to these guidelines.

Archived information

This chart contains links to pages that include information that is historically important but not being maintained. This information includes inventories, proposals and analysis.

Category Description Link When archived
Inventory Detailed inventory of motorways, trunk highways and expressways link 26 January 2022
Motorway & Expressway Original proposal link 24 January 2022
Discussion & conclusions about original proposal link 26 January 2022
Motorway island survey results and conclusions link 6 March 2022
Proposal version 2 link 6 March 2022
Expressway Proposal in September 2022 to conform to then-current US Highway guidance link 30 October 2022
Trunk highways Version 4 (agreed) [includes versions 1, 2, and 3] link 14 April 2022