Kind of cool if it turns out to have validity. The idea is that the lines have something to do with marking underground water sources, like wells. Note that no alien help would be needed for this, either. Here’s what’s needed: (1) knowledge that there is water / a well / a stream under your feet; (2) the notion that “hey, we should mark where this is”; and (3) adding an artistic flair to the markings — and devising a way so that one points to another.
At some point I need to post on the Nazca lines. Very interesting and often-studied item.