To provide a method of mobile type for taking deep water required in a measure against shore ruining using the deep water and a multipurpose working device for mobile ocean deep water intake, water supply, and water sprinkle.

A thermally insulated water storage tank in a floating body 110 and a water intake device 10 for taking the deep water at a depth of 200-700 m are provided, and the deep water taken by the water intake device 10 is stored in the water storage tank for transporting.