Write-up

Path of Flood Trail
Line Name   surface  routes  total miles  gap  off_road  on_road  closed  unknown  other   
map Passage under Rail Tracks.  Trail Open Surface Unspecified  pathofflood,ne,pgh-harr,  0.0889    0.0889            
map /pathofflood10.kml 672  Trail Open Surface Unspecified  pathofflood,ne,pgh-harr,  0.8065    0.8065            
map Johns Street to Roosevelt Blvd  Trail Open Surface Unspecified  pathofflood,ne,pgh-harr,  0.5331    0.5331            
map Jim Meyer Riverwalk  Trail Open Surface Unspecified  pathofflood,ne,pgh-harr,  1.3297    1.3297            
map Mineral Point to Erenfeld  Trail Open Surface Unspecified  pathofflood,ne,pgh-harr,  2.621    2.6210            
map trhough Mineral Point  Road Low Volume Asphalt  pathofflood,ne,pgh-harr,  0.6015      0.6015          
map Staple Bend Trail  Trail Open Surface Unspecified  pathofflood,ne,pgh-harr,  2.8391    2.8391            
           
Path of Flood Trail  total for Trail    8.8198    8.2183  0.6015          
           

Trail Lines are typically entered by tracing satellite imagery to extract latitude/longitude coordinates. The accuracy of these coordinates changes depending on the source of the photo and the precision of placement. I have seem satellite edges mismatched on the order 55 feet. Line work is sometimes extracted from the Open Street Map Project and from Strava heat maps.
>Milepost Known milepost (are placed on the map when they are visible in the satellite image or can be located via to visible features in the image. Other miles posts are extrapolated using calculations along the rail line. Note Railroads have also been known to realign trackage and not move existing mileage markers, only making an annotation on their paper maps.
Distances Above are based on the google map distance between two points along the line work.