Final answer:
The sewing of a plastic tarp to a geotextile section provides the protective cover with watershed characteristics.
Step-by-step explanation:
The seam formation that provides your protective cover with watershed characteristics during fabrication is the sewing of a plastic tarp to a geotextile section.
The cover used in this case is made of a traction-resistant plastic tarp sewn to a geotextile section, which is used in construction. This seam formation ensures that the cover is watertight and prevents water from seeping through.
By sewing the plastic tarp to the geotextile section, the cover is able to effectively repel water and provide a protective barrier that acts as a watershed.