User:Whoaitspete/Bridges Draft

For the Bridge Segments function in WME, see Creating and editing road segments and Overpasses, Underpasses and Bridges.

A bridge place is used to represent a named bridge with local or navigational significance. With more than 600,000 bridges in the US, these guidelines are in place to prevent app clutter from polygons, labels, and search results of bridges with little to no significance for navigation.

In general, a bridge place should only be mapped if its significance entails: 1. An official and/or locally-used name, such as a signed name, a name used in traffic reports, or a commemorative name that differs from the feature the bridge crosses or the road that crosses the bridge 2. Use of the bridge as a destination, waypoint, and/or landmark for navigation

Bridge Place

Bridge places serve as a routing destination and/or a landmark in the app. As destinations, these places allow users to navigate to a bridge for purposes such as visiting a pedestrian accessible bridge, driving to the designated viewing area of a non-accessible bridge, or adding the bridge as a stop during navigation to get a preferred route. As a landmark, a bridge place is represented by a label and polygon on the map to help users orient themselves.

Geometry

Bridges should be added as area places. The geometry of the polygon should be limited to the area of the bridge span(s) and, for multi-span bridges, care should be taken not to cover any significant open area between spans. This prevents the area place layer from covering portions of other map layers between the spans in the app.

Given their height above ground level, bridges are subject to parallax on aerial imagery. This may cause the bridge to appear shifted, curved, and/or wavy in WME imagery compared to its actual position. To resolve this issue, a bridge place should be drawn offset from its position on the imagery to match the segments that cross the bridge when available (see more about segments below).

Example of preferred geometry for a multi-span bridge. Note that the polygon is shifted south from the bridge on the imagery due to parallax.

Address

If the bridge is an active road bridge, use the street name and city of the segments crossing the bridge with no HN. If the segments on the bridge are divided and labelled for each direction, the street name should not include the cardinal direction.

When a bridge crosses two or more city names within a state:

• If the segments share a common street (primary or alternate), select that street name and check the none box for city
• If the segments do not share a common street (primary or alternate), check the none box for street and city

If a bridges crosses state or country borders, select the state that encompasses a majority of the bridge or consider mapping two area places in their respective state and/or country.

Non-road bridges that are destinations should have their address set to their main entry point. If a non-road bridge is added purely as a landmark and/or would not be navigated to (e.g., active railroad bridge with no designated viewing area), do not add a street or HN in the address category.

Bridge officially named after and signed for the feature it crosses (top) versus a unnamed bridge only signed for the feature it crosses (bottom)

Name

This should be an official or locally-used name, preferably signed at each approach. Do not map unnamed bridges signed only for the feature they cross or the name of the road that crosses the bridge, unless this is an official name of the bridge. Bridge areas may also be used to add a signed or known commemorative name that is different than a bridge name which is used in the street name. Bridges should follow the general standards for naming Places; do not abbreviate the word "Bridge".

Categories

In addition to bridge, add any categories relevant to the bridge as a destination. These may include categories such as Tourist Attraction/Historic Site, Scenic Lookout/Viewpoint, Park, etc. Do not add additional categories to bridges that serve only as a landmark.

Entry Points

As of April 2021, Multiple Entry Points (MEPs) are not usable in the production app. When adding entry points, keep in mind that production users are routed only to the originally created entry point.

Entry points should be added according to the navigation needs of the bridge place:

• As a destination
  • If a bridge has (a) parking area(s) for pedestrian access near the approach for the bridge and on the same road, they should be set as an entry points and named accordingly.
  • If a bridge does not have pedestrian access but has a nearby lot designated for viewing, the entry point should be set to that lot
  • If a bridge is added purely as a landmark, do not add an entry point unless it is necessary to prevent undesirable routing (e.g., routing to a nearby interstate, private driveway, etc.).
• As a routing aid
  • For single span with an undivided road, add a single entry point that allows a route to come from either direction. If the bridge already has a destination entry point near the approach to one or both sides of the bridge, this point does not need to be added.
  • For a single span with divided roads or multi-span bridges, an entry point should be added at the entrance of the bridge from each direction to allow routing from the selected direction. The name of the points should indicate the direction of the segment they are set to.

Lock

Completed bridge places should be locked to at least 2, though regional guidance may suggest a higher level based on road type, landmark importance, etc.

Segments Crossing Bridges

The addition of or edits to a bridge place may also require edits to the segments utilizing the bridge, given the association of their geometry, names, and navigation purposes.

Geometry

Like the geometry of the bridge place, bridge segments are subject to parallax and the resulting offset can be significant enough to disrupt the app's snapping algorithm. Segments should be adjusted to compensate for this shift by using the GPS points layer or official sources to align the segments to their real-world position.

Name

Drivable segments crossing a bridge should follow road name standards and should not be changed solely to the name of the bridge unless it is the road's official name. If the bridge's significance warrants the inclusion of the name for navigation purposes (i.e., as part of the "let's take..." TTS at the start of navigation, in hazard, closure, and other reports, etc.), the bridge name can be appended to the primary name using a bullet (•) and proper abbreviations and acronyms (e.g., "I-75 N • Mackinac Br").

Non-drivable segments that cross a bridge should follow their standard naming conventions, including no name if applicable, but should not be appended with the bridge name since it provides no navigational benefits.

Elevation

Segment elevation should be set according to regional elevation guidance.

Examples

• Bridge place versus no bridge place
  • Meridian Bridge - Old bridge (bridge place) next to modern, unnamed US-81 bridge (no bridge place)
• Bridge with destination entry point(s)
  • Dingman's Ferry Bridge - Entry point as both a tourist destination and as a routing aid as a preferred river crossing
  • Walkway Over the Hudson - Pedestrian bridge accessible by parking lots on each end
  • Starrucca Viaduct - Non-accessible historic railroad bridge with viewing area in a nearby park
• Non-accessible bridge set only as a routing aid
  • Mario Cuomo Bridge - Routing aid entry points set for each direction (typically a preferred crossing by users instead of using bridges/tunnels near NYC, not always given as a route due to routing server limitations). While the bridge has pedestrian access, the access to these paths are off of the interstate that crosses the bridge and are mapped separately.
• Landmark only bridge
  • Alfred H. Smith Memorial Bridge - Major railroad bridge with no designated viewing area but useful as a visual aid