Road file attributes

The access file is a combination of the existing and candidate future roads. These roads should exist in a single spatial file (coverage or shapefile). No matter how you process your road data the rows in the feature file should be described by the following type of fields (in either a shapefile or a coverage):

Table 15. Required fields for spatial route data

FNODE_ or FNODE#The starting vertex (node) id for the line segment.
TNODE_ or TNODE#The ending vertex (node) id for the line segment.
LENGTHThe total length of the line segment in meters. This field will be used to calculate cost information on a per km basis within the road network but can also be used within Patchworks to report on the active road length, active road by road type, etc.
Unique segment idA unique identifier for each segment. Unlike the other columns there is no fixed name for this column. The tool that processes this file will prompt for the name to use.

A classification of the line segments into categories that are used for descriptive purposes. Any number of categories can be defined. Usually this type of classification represents the speed at which wood could be hauled on a particular segment thus changing the cost characteristics. These classification may have similar cost characteristics for maintenance and construction as well as hauling. Some examples of road type classifications strings are:

  • Highway (H)

  • Primary (P)

  • Secondary (S)

  • Tertiary (T)

  • Candidate (C)

BUILD The cost in dollars to construct the road segment. This value could be based simply on the road type classification or could be derived from more advanced GIS operations. For example, this number could increase based on the distance from closest aggregate source or based on the type of substrate. This field is only relevant for roads that do not already exist in the route dataset. The dataset could however include planned road corridors or planned road sections that would have an associated construction cost.
MAINT The cost in dollars to maintain the road segment. This value could be based on the simply road type classification or could be derived from more advanced GIS operations. Considerations for maintenance may be snow removal, culvert repair, bridges and grating and depend on the surface type of the road segment.
HAUL The cost in dollars of hauling a cubic metre of wood on the road segment. Again, this may be based on the road type classification of the segment or on more advanced GIS operations (for example, slope or speed limits). The model will use this number to calculate the haul cost by multiplying the volume of wood crossing that segment.

Specifies whether the segment can be used in one direction or two directions. The model will recognize and interpret the following values:

  • 1 - single direction FNODE to TNODE

  • 2 - single direction TNODE to FNODE

  • 3 - both directions (no restrictions)


Additional fields can exist in the final road access file and will be ignored by Patchworks. For example, some intermediate values can exist in the file to help in cost calculations.