MEUST (Mediterranean Eurocentre for Underwater Sciences and Technologies) is a second generation permanent submarine observatory to be deployed offshore of Toulon, France, as a follow up of the pioneering ANTARES neutrino telescope. The MEUST submarine network has a modular topology designed to connect up to 120 neutrino detection units,i.e. ten times more than ANTARES. This may allow to instrument one km3 of water for neutrino astronomy or, with a denser instrumentation, several Megatons for measurement of neutrino properties, and to deploy sensors for environmental sciences on an array of ten km. The topology and functionalities of the network comply with the specifications of the KM3NeT neutrino telescope, which plans to use MEUST as one of its 3 deployment sites, as well as with those of the environmental sensors developed for the Ligurian site of the EMSO submarine observatory network. The technical solutions developed for the MEUST infrastructure are adapted to any large deep sea detector array located within 50 km from the coast. After a brief reminder of the MEUST scientific motivation and submarine sensors, this document details the technical design of the infrastructure and summarizes the organization of the project