User:Aweech/Draft:New Hampshire highways

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This is a draft of content to use on the New Hampshire page as replacement for the minimal road tagging guidance. It is based on discussions on Talk-us: US Trunk road tagging and the OSMUS Slack. Feel free to discuss or help edit this content prior to any inclusion on New Hampshire.

This page is planned to appear on the New Hampshire OSM Wiki page in order to help mappers make decisions about how to classify roadways in the state. It was developed in collaboration with mappers from across the northeastern United States, and the community in Vermont has already implemented similar guidance. The guidelines here were developed to try to reflect existing practice as much as possible. However, there are two major changes to the guidance. The first is to bring the definition of highway=trunk in line with what has long been used in other parts of the country and much of the world. The second is to expand the use of highway=tertiary and highway=unclassified, which are currently not used as much as they should be due to them not being included in the TIGER import.

Roads in New Hampshire

The general-purpose road network

In OSM, roadways are primarily categorized using a highway=* tag that indicates the roadway's importance in the road network. Because OSM is a global map, it is important that there is consistency locally, regionally, and globally in how roadways are slotted into the 8 highway=* levels the general-purpose road network:

  1. highway=motorway
  2. highway=trunk
  3. highway=primary
  4. highway=secondary
  5. highway=tertiary
  6. highway=unclassified
  7. highway=residential
  8. highway=track

It is important to note that the values of the highway=* tag come from the British road classification system, but, globally, they are applied as hierarchy of descending importance with highway=motorway being the only level that demands compliance with physical construction standards. All lower levels from highway=trunk to highway=residential are based on their importance to the road network.

1: highway=motorway

The top category, highway=motorway should only be applied to roadways that are either signed Interstate highways or have ALL of the following characteristics:

  • Limited access
  • Divided highway
  • Designed and maintained to support average speeds to at least 50 mph in urban areas and 65 mph in rural areas
  • Facilitate long distance travel at high speeds, or provide service in or between the more heavily populated areas of the state.

The only roads that should be tagged as highway=motorway in New Hampshire are the Interstates (I-89, I-93, I-95, I-293, I-393), non-Interstate highways built to the same standard (NH 101 between Manchester and I-95, the Spaulding Turnpike, and the Everett Turnpike), and short spurs from these ways like Hudson's Circumferential Highway. Other roadways that meet some, but not all of the criteria (such as NH-101 near Milford) should not be tagged with highway=motorway, but rather another highway classification that represents their importance in the regional road network, with expressway=yes and access_control=partial to indicate their enhanced level of construction.

2. highway=trunk

As the top non-motorway classification, highway=trunk should be applied to non-motorway roads that:

  • Serve as the principal connectors:
    • Between two cities of regional importance in cases where the cities are not directly connected to each other by highway=motorway; or
    • Between cities of regional importance and roads tagged highway=motorway
  • Are of a sufficient physical construction that they represent the shortest vehicular route between the two cities

In and around New Hampshire, the list of cities of regional importance includes:

  • Albany, NY
  • Boston, MA
  • Sanford, ME
  • Portland, ME
  • Keene
  • Nashua
  • Manchester
  • Concord
  • Portsmouth/Rochester/Dover (these cities are too close to one another to treat separately)
  • Laconia
  • Franklin
  • Lebanon
  • Claremont

Therefore, the following routes should be tagged as trunk:

  • NH 9, between VT and I-89 (Albany, NY - Keene - Concord)
  • NH 101 between Keene and Bedford (Keene - Manchester)
  • NH 101A between NH 101 and Everett Turnpike (Keene - Nashua)
  • NH 12 between MA and Keene (Boston, MA - Keene)
  • NH 125 from Epping to Spaulding Turnpike (Nashua - Manchester - Seacoast)
  • US 4 from I-393 to Spaulding Turnpike (Concord - Seacoast)
  • NH 11 from Rochester to Claremont (Seacoast - Laconia - Franklin - Claremont)
  • NH 12 from Claremont to I-91 (to connect Claremont to the Interstate network)

Also, being a state with 4 neighbors, there are roads that do not connect urban areas within New Hampshire, but do provide important connections for residents in other territories. These include

  • NH 26 from ME to Colebrook (Portland - Montreal)
  • US 3 from Colebrook to the bridge to Canaan, VT (Portland - Montreal)
  • US 2 through the whole state (Augusta - Burlington)
  • US 302 from ME to NH 16 (Portland - the White Mountains)
  • NH 16 from Rochester to US 2 (Boston - the White Mountains)

The trunk classification may also be used within urban areas themselves. A trunk road in an urban area should be a partially controlled access highway or expressway. Examples of these kinds of highways include:

  • NH 101 from I 95 to Hampton Beach (partially controlled access)
  • US 1 Bypass in Portsmouth (expressway closed to non-motorized traffic)
  • The first few hundred meters of the Spaulding Turnpike in Portsmouth (expressway closed to non-motorized traffic)
  • US 202 between I 93 and US 3 in Concord (expressway)
  • The super-two portion of NH 12 northwest of Keene (controlled access)

3. highway=primary

This second-level of non-motorway roads should be applied to US highways and higher-importance state routes that aren’t highway=trunk. As a guide, many Tier 2 roads (statewide corridors) should be tagged as trunk or primary. Examples of state routes tagged as primary include NH 106 south of Laconia, NH 28, NH 111, NH 104, and NH 25). Also some extremely important urban roads like the Daniel Webster Highway in Nashua and Granite Street in Manchester should be tagged as primary.

4. highway=secondary

This categorization level should be applied to middle-importance state routes and very important urban streets. This would be most state highways that do not have a higher-level classification. These roads are often built to lower standards that the ones above. Examples include: NH 107, NH 109, and NH 132. Bridge Street in Manchester is an example of a very important urban street that is not a state route tagged as secondary.

5. highway=tertiary

Unnumbered state roads (identified by the begin and end state maintenance signs) and important through roads in urban compacts. Unnumbered state roads can begin and end in places that are not intersections, and tertiary classification should be carried in a way that makes sense to a nearby road of equal or higher rank (for example Canterbury Road in Chichester is only a state road for a mile or two, but it is classed as tertiary all the way to King Road and Main Street). Some alternate state routes that only serve one community should also be classed as tertiary, for example NH 113B in Chatham.

6. highway=unclassified

Any other less-important connecting or non-residential road. This includes less-important rural roads that connect other less-important rural roads and residential roads.

7. highway=residential

The smallest and least important roads (from a connectivity standpoint). Many higher-classification roads have residences along them, so the presence of residences does not demand that a road be tagged as highway=residential. Rather, highway=residential should be used for roads that are primarily used to access residences. If there is no reason to take a road than to access the houses along it, then there is a good chance that highway=residential is the appropriate classification. The presence of another type of facility such as a business or trailhead doesn't necessarily negate highway=residential's applicability.

8. highway=track

These are roads that serve no connectivity function to motorized users. There are three types of road that should be tagged as track in New Hampshire.

  • Class VI roads that are not privately maintained to access properties. Class VI roads that are privately maintained to access properties should be tagged as either residential or service depending on how many houses are along it. Class VI roads should also be tagged with access=yes and any special regulations the town or city has created.
  • Discontinued roads where there is evidence of motorized use. These roads should be tagged with ownership=private unless a government is an abutter.
  • Roads servicing farmland and logging areas within properties. These roads should also be tagged with ownership=private unless the road is on a government-owned property.

Bureau of Trails Trails

A typical access posting on a Bureau of Trails trail

The Bureau of Trails (BoT) maintains a network of trails through the state. Some of this is on private land, and each landowner can post restrictions on the trails if they want. The most common tagging scheme for BoT trails on private land is highway=path + access=permissive + snowmobile=designated + atv=no + motor_vehicle=no. The BoT also owns trails outright and regulates access to them. These should be tagged with highway=path + foot=yes + horse=yes + bicycle=yes + snowmobile=yes + ski=yes + bicycle=yes + dog_sled=yes.

Department of Transportation Bike Paths

The Department of Transportation (NHDOT) is authorized to create bike paths under RSA 12-B:4. These paths should be tagged with highway=cycleway + foot=no where the way is adjacent to a motor highway and highway=cycleway otherwise. As best as we can tell, there are no such paths in the state. However, the NHDOT has created some pathways that it calls "bike paths" that do allow pedestrian access, even where the way is adjacent to a motor highway. These should be tagged with highway=cycleway + foot=yes. NHDOT also has a network of designated "bike routes". These are different from true bike routes (defined in RSA 230:75), which are required to be signed, and should not be included in OSM.

Ownership and Access

Due to the cost of road maintenance, there is a strong financial disincentive for New Hampshire towns to take over responsibility for small residential roads that only provide access to a few residences. As housing is built in an area the new roads default to being owned and maintained privately. These roads may be named and signed for wayfinding and E911 purposes, but their signs will include a "private" or "PVT" label, or be colored differently, to indicate that they are privately owned and maintained and that the Town is not responsible for their maintenance. Roads designated as "private" in this way should be tagged with ownership=private. Residents can petition their Town to accept a road, which would then lose it's "private" label and become ownership=public or ownership=municipal. Named private roads that serve 2 or fewer dwellings or businesses should be tagged as highway=service.

In contrast to this ownership and maintenance label, some roads may be signposted with signs say "No Trespassing", "No public access", "Keep out", or similar wording -- these should be tagged with access=private to indicate that the public is not allowed to use this road. Do not add access=private to roads simply because they are privately owned and maintained.

Other roads

Not all roads are part of the general-purpose road network. In addition to those above that are usually (though not always) publicly accessible and maintained, there are also highway=service roads for accessing buildings and facilities, and other special-purpose roadways such as highway=raceway. See highway=path for "roads" that are intended for non-motorized use.