<div dir="ltr"><p></p><p>There seems to have been a certain number of edit wars over the classification of various major bridges in New York City. As far as I can tell, there's no consistent method used here right now for determining whether a bridge is <span style="font-family:monospace">highway=motorway</span> or <span style="font-family:monospace">highway=trunk</span> or <span style="font-family:monospace">highway=primary</span>.<br></p>
<p>One of the main criteria for what is a <code>highway=motorway</code> 
is that it has no intersection controls on the main roadway (such as 
traffic-signals, rotaries and roundabouts, and stop signs or stop 
markings). Bridges usually don't have intersections, so that is not 
useful here. Another is that the different directions are physically separated, this applies to most of the bridges.</p>
<p>Another important factor is that <code>highway=</code> tags should 
apply where reasonable to the whole road, not just a segment of it. Many
 of these bridges were built to carry a major street, but when highways (<code>highway=motorway</code>s)
 were built later ramps were added only where convenient, resulting in 
incomplete interchanges with them. Whether the bridges are considered an
 extension of the highway or the major street might factor in.</p>
<p>I'm hoping we can come up with a reasonable method for determining what <code>highway=</code> tag bridges like these should have.</p>
<p>In the below table I've catalogued some area bridges with varying 
characteristics. The Carries column gives the street the bridge was 
built to carry and its classification. The <code>motorway_link</code> column counts the number of directions on the bridge that can be entered/exited (each counting 1) from a <code>highway=motorway</code>.
 This ignores that not all lanes/roadways go to all exits or all 
directions on the connecting motorway etc. Vehicles only is whether 
bicycles and limited-use motorcycles are banned from the main roadway as
 indicated by signage.</p>
<table>
<tbody><tr>
<th>Bridge</th>
<th>Carries</th>
<th>motorway_link</th>
<th>Separate roadways</th>
<th>Pedestrian separation</th>
<th> Vehicles only<br></th>
<th>Present tagging</th>

</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/Brooklyn_Bridge">Brooklyn Bridge</a></th>
<td>highway=primary Adams St</td>
<td>3/4</td>
<td>Separate</td>
<td>Separate</td>
<td>Yes</td>
<td><a href="http://osm.mapki.com/history/way.php?id=432550255">highway=trunk</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/Manhattan_Bridge">Manhattan Bridge</a></th>
<td>highway=primary Flatbush Ave Ext</td>
<td>1/4</td>
<td>Separate</td>
<td>Separate</td>
<td>Yes</td>
<td><a href="http://osm.mapki.com/history/way.php?id=46189305">highway=trunk</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/Williamsburg_Bridge">Williamsburg Bridge</a></th>
<td>highway=primary Delancey St</td>
<td>2/4</td>
<td>Separate</td>
<td>Separate</td>
<td>Yes</td>
<td><a href="http://osm.mapki.com/history/way.php?id=40337615">highway=motorway</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/Queensboro_Bridge">Queensboro Bridge</a></th>
<td>highway=primary NY 25/NY 25A</td>
<td>0/4</td>
<td>Separate</td>
<td>Separate</td>
<td>Yes</td>
<td><a href="http://osm.mapki.com/history/way.php?id=198924625">highway=motorway</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/Triborough_Bridge#Harlem_River_lift_bridge_(NY_900G)">Triboro Bridge (Manhattan span)</a></th>
<td>highway=motorway NY 900G (unsigned)</td>
<td>4/4</td>
<td>Separate</td>
<td>Barrier</td>
<td>Yes</td>
<td><a href="http://osm.mapki.com/history/way.php?id=5669174">highway=motorway</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/Willis_Avenue_Bridge">Willis Ave Bridge</a></th>
<td>highway=primary Willis Ave</td>
<td>2/2</td>
<td>One-way</td>
<td>Barrier</td>
<td>No</td>
<td><a href="http://osm.mapki.com/history/way.php?id=5670524">highway=primary</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/145th_Street_Bridge">145th St Bridge</a></th>
<td>highway=secondary 145th St</td>
<td>0/4</td>
<td>No</td>
<td>Curb</td>
<td>No</td>
<td><a href="http://osm.mapki.com/history/way.php?id=5670765">highway=secondary</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/Washington_Bridge">Washington Bridge</a></th>
<td>highway=secondary 181st St</td>
<td>4/4</td>
<td>Median</td>
<td>Barrier</td>
<td>No</td>
<td><a href="http://osm.mapki.com/history/way.php?id=33117565">highway=motorway</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/University_Heights_Bridge">University Heights Bridge</a></th>
<td>highway=primary Fordham Rd</td>
<td>0/4</td>
<td>No</td>
<td>Barrier</td>
<td>No</td>
<td><a href="http://osm.mapki.com/history/way.php?id=19174360">highway=primary</a></td>
</tr><tr>

<th><a href="https://en.wikipedia.org/wiki/Broadway_Bridge_(Manhattan)">Broadway Bridge</a></th>
<td>highway=primary US 9</td>
<td>0/4</td>
<td>Median</td>
<td>Curb</td>
<td>No</td>
<td><a href="http://osm.mapki.com/history/way.php?id=126140593">highway=primary</a><br></td></tr></tbody></table></div>