The sky survey with high energy neutrinos is complementary to the survey with photons and will allow to better understand the mechanisms of emission and acceleration of cosmic rays. The detection of galactic and extra-galactic sources needs a huge under-water(ice) detector (1km#tex2html_wrap_inline736#). Compared to the old generation detectors this represents a great improvement in volume (#tex2html_wrap_inline738#SuperKamiokande) and a new method to work. Several projects are working or are in project. They may be considered as the prototypes of the future detector.