Method of installing a flexible riser

A method of installing a riser to provide a continuous flow path from a relatively rigid pipeline lying on the bottom of a body of water to an above water connection on an offshore apparatus is disclosed. The riser according to one aspect of the invention is a tubular flexible conduit and in a second aspect is a rigid member connected to the pipeline by a flexible section. The method of the invention for installing the riser uses available equipment, relatively small lifting forces and avoids the deformation of rigid pipe. In one particular embodiment, the pipeline-riser combination is laid on the bottom of the body of water and according to the method, the riser member is thereafter raised to a vertical orientation with respect to the offshore platform. The method provides a riser which does not undergo deformation at the bending zone wherein fluid flow changes between the horizontal and vertical directions.