The places with strong tidal currents have a tendency of limiting construction to ebb and high tide, in other words lot of expensive waiting around. Regarding

The places with strong tidal currents have a tendency of limiting construction to ebb and high tide, in other words lot of expensive waiting around. Regarding the environment, under the sea it is quite fine compared to stationary platforms operating in the north sea or Mexican gulf(hurricanes) year around, so that should be easier.