Abstract: An apparatus and method are provided for dewatering an interior of a hollow tension leg connecting a tension leg platform to a floor of a body of water. The apparatus includes a pump having a suction inlet defined on its lower end and a discharge outlet on its upper end. An elongated storage tank is attached to the upper end of the pump above the pump and has a tank interior communicated with the discharge outlet. The assembly is lowered on an electric wireline through which power is conducted to the pump. The pump fills the tank and then the assembly is withdrawn from the tension leg and the water is drained therefrom. The assembly can be repeatedly lowered into the tension leg and withdrawn therefrom until the tension leg is substantially completely dewatered. Solid debris can be removed from the tension leg prior to dewatering.