A method for magnitude constrained phase contrast magnetic resonance imaging (MRI) is provided. The method utilizes an assumption that the image magnitude is shared across a series of images reconstructed from a set of phase contrast enhanced k-space data. In this manner, one common magnitude image and a plurality of phase images are reconstructed substantially contemporaneously from the acquired image data. The method is further applicable to other phase contrast MRI methods, such as phase contract velocimetry. Moreover, simultaneous phase contrast velocimetry and chemical shift imaging, in which water and fat signal separation is achieved, is provided.