X Marks the Spot: Knowing Where the Drain is

In every basement floor, by virtue of most building codes, there must be drain, and the floor must slope towards those drains.  However if you are finishing the floor, as we did with Dricore under-flooring with a laminate flooring finish, then these drains may be covered.

I believe it is important to at least remember where the drains are for future reference.  We have chosen to simply mark or measure and record the position of the drain.

What do think the correct practice should be?
  1. Mark or record the location but keep covered? or
  2. Cut a hole corresponding to the drain and install a low profile drain cover in the floor covering?
Related Links:
DriCore - The Revolutionary Subfloor System - Step-By-Step Installation Video