A valve assembly including a main body, a gate and an actuator. The main body defines a fluid chamber, with an inlet fluidly coupled to the fluid chamber, and an outlet also fluidly coupled to the fluid chamber. The gate has a first portion and a second portion connected to one another and both are subjected to a fluid pressure within the fluid chamber. The first portion is configured to close the outlet when the fluid chamber is pressurized due to a closing fluid force acting on the first portion. The second portion provides a counter- acting fluid force to the closing fluid force when the fluid chamber is pressurized. The actuator is coupled to the first portion or the second portion and is configured to provide a net opening force on the gate to open the outlet.