I am wanting to show the distance of the "Restoration Path" Line at the bottom of my legend manually, as I haven't found another way to display the distance in the legend. My plan is to write a simple bit of text at the bottom of the legend such as "Restoration Path Distance: 1000 meters".
Does anyone know how to either automatically display the length of the "Restoration Path" line in the legend or to leave a gap between the last legend item and the bottom border to manually insert that info?
You can leave a gap between the border and the legend by adjusting the X and Y gaps on the Display tab of the Element pane.
Only downside to that approach for this particular purpose is that adjusting the Y gap would also expand it above the legend too.
One way is to create another marker, move to bottom of the points legend, and set color to Null ("West" in below example).
Then you can add text as you wish. In this case, I used dynamic text, pulling "Value" from the table of the line feature class, then appended the "ft".
If this was the only restoration path you needed with that name, you could just change the layer name to be Restoration Path: 1000 meters and that is how it would show in the legend.
You could also convert the legend to a graphic and edit it that way.
Why not just create a Rectangle type text box with the static text and format the box to have the same colour background and width as the legend and position it below the legend (but on top of it in the table of contents to the legend doesn't cover it up).
Additionally, you might be able to use the Dynamic text option instead of static text to place the Sum of a length field (i.e. Shape_Length) if it is in a Projected coordinate system. Add and modify dynamic text—ArcGIS Pro | Documentation