Ummmm, I highly doubt this to be true. Let me qualify myself. I lived in Peru, my wife is Peruvian, and we return when we can.
Tumbes is located in the far north of Peru, all the way up by Ecuador. Tumbes is a tourist destination for the rich in Peru, but it's not the easiest place to get to. Flying is the best way to get there, by bus it sucks. There's not a lot of population there to sustain it either. Lima, which is where 1/3 of the population of Peru lives is a long ways away.
I have a feeling this is a hotel being built with some water slides and other nice ameneties. There's an awesome place in Ica Peru called Las Dunas that would probably be similar to what's being built.