<p>A lower riser assembly connects a riser to a seabed mooring and to a subsea hydrocarbon fluid source. The assembly includes sufficient intake ports to accommodate flow of hydrocarbons from the hydrocarbon fluid source, as well as optional flow assurance fluid. The upper end of the member has a profile suitable for fluidly connecting to the riser. The lower end of the member includes a connector suitable for connecting to the seabed mooring. An upper riser assembly connects the riser to a near-surface subsea buoyancy device and to a surface structure. The assembly includes sufficient outtake ports to accommodate flow of hydrocarbons from the riser through a subsea flexible conduit to the surface structure. The upper end of the member includes a connector for connecting to a subsea buoyancy device. The lower end of the member comprises a profile suitable for fluidly connecting to the riser.</p>
