The Latin American Giant Observatory (LAGO) is an international experiment with multiple scientific objectives. These objectives include the study of the extreme universe, space weather and atmospheric radiation at ground level. The observatory is composed of several experimental sites, distributed in the American continent, from Argentina to Mexico. The highest LAGO site is located on the Chacaltaya mountain, Bolivia, at an altitude of nearly 5300 m.a.s.l. In this document we report the status of the experimental site on Chacaltaya. In particular, emphasis is given on the development of a water Cherenkov detector. We describe the pilot detector that we are assembling, the energy calibration method and the characterization of the PMT employed.