An apparatus and method for providing a controllable supply of fluid, and optionally power and/or communication signals, to a subsea equipment are provided. The fluid may be a water-based fluid, oil-based fluid, or chemicals. The apparatus includes a reservoir disposed on a seabed for storing a supply of fluid for delivery to the subsea well equipment. A subsea pumping device is configured to receive the fluid from the reservoir, pressurize the fluid, and deliver the pressurized fluid to an accumulator of a hydraulic power unit disposed on the seabed. The hydraulic power unit can store the pressurized fluid and control an output of the pressurized fluid to the subsea well equipment, thereby providing a subsea fluid source for the subsea equipment.