The 2015 Awards and Judging Policies pdf file contains the following:
The notebook may be delivered in electronic format (PDF only) or in physical format as determined
by the local hub and regional championship.
NOTE: The preferred delivery format is electronic (PDF). Please see the
Awards and Judging – Hub Logistics document for the specified
format and information on when and how the notebook is to be
So you'll have to ask your Hub contacts, and Regional if you get that far.
Many of the regionals like Texas BEST are requiring electronic only format,
to remove the logistical issue of moving the physical notebooks.
Sometimes you can use photo editting tools to change the contrast to help your sketches
be seen. Or duplicate them with CAD, or just go over them with a darker pencil.