Abstract: A method of dewatering a subsea pipeline bundle assembly before lifting the assembly from the seabed comprises adding discrete buoyancy to an elongate carrier pipe of the assembly. The buoyancy elevates one or more portions of the carrier pipe disposed between drainage outlets of the assembly. Each elevated portion defines inclined falls that slope downwardly in opposed longitudinal directions toward the respective outlets. Water within the carrier pipe drains down the falls toward the outlets. Injecting a dewatering fluid into the carrier pipe promotes expulsion of water from the pipe through the outlets by downward displacement of the water. Drainage can be assisted by a venturi effect driven by accelerating the flow of the dewatering fluid at a location in line with an outlet.