Introduction

This is a step by step guide on how to classify Roadway Centerline lanes within the RCE editor. In addition to methodology, we will discuss general rules and rule exceptions.

Initiation

Before roadway attribute classifications can begin, a segment must be identified and directionality must be established for both the segment and the individual lanes/features within that segment. Defining a segment is dependent on feature classifications whereas directionality will follow a general rule.

Segment Directionality

Data are always collected in the ascending LRS geometry direction. Determining this direction is dependent on which DC quadrant a segment is in.  For example, if you are in the Northeast quadrant centerlines will either ascend to the north (for a mostly north/south facing roadway) or to the east (for a mostly east/west facing roadway).  Below is a graphic which should help to visualize this.

Lane Directionality

Once the segment directionality is determined then Lane 1 must be identifed. The numerical identifier for roadway sections will always increase from left to right starting at the origin measure of that section. In laymen terms, if you're standing at the "0" or start point of the segment and facing toward the end point of the segment then inbound would be towards you and outbound would be away from you, lane measures would move left to right. 

The visual below will give the general basis for this identification

Here are some general rules regarding segment and lane directionality:

• Lane 1 is typically going to be Inbound.
• Sidewalk directionality will typically follow the roadway direction adjacent.
• Lane directionality is based on segment directionality and quadrant.

Here are some general rule exceptions regarding segment and lane directionality:

• Interstates geometry may ascend in other directions (typically, this is because they can cross over quadrants without a break).
• Alleyway geometry may ascend in other directions.
• One way roads - Lane 1 may be outbound.

Classification - Step by Step

In order to relfect the most accurate current conditions for this project, Nearmap aerial imagery and Streetsmart by Cyclomedia street view was used for data capture. Here's how we used those tools to code the data in the RCE editor:

1. Setting up the Editing tab
   
   1. The "Roadway Updates" attribute set must be loaded in.
   2. The "Enable snapping" option must be selected.
   3. The "Layer: Roadway" must be selected.
      
      
      

2. Creating a New Line Event

1. 1. Select "Line Events" to open the "Add Linear Events" editor.
   2. Using the Roadway Selection tool, select the roadway you intend to code and the "Route ID" field will autofill.
      
      
      
2. Selecting the Line Segment to be Classified
   
   1. Using the "From" Measure Selector, select the from Measure in which you would like to begin a segment.
   2. Using the "To" Meaure Selector, select the measure in which you would like to end a segment.
   3. Make sure that "retire overlaps" is selected (checked).
   4. Go to "Next."
      
      
      
3. Identifying Roadway Sections
   
   1. Check on/off the correct number of roadway sections in your segement (each roadway section has a correcponding pavement section).
   2. Using the drop downs- select the section type, width, lane direction and pavment type for each roadway section based on Nearmap Aerial imagery (with street smart street view for verification).
      
      
      
4. Identifying Sidewalks
   
   1. Check on/ off which sidewalks are present.
   2. Determine width and pavement type based on Nearmap Imagery.
   3. Select Go to next measure upon save (if you wish to continue with the same segment at that time).
   4. Save and Continue 

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