Control of a linear time-varying uncertain dynamical system with delayed inputs is considered. The model parameters, disturbance inputs and model structure errors are unknown but bounded, and the parameter value can abruptly change. The objective is to keep the system output within prescribed limits regardless of the uncertainty scenario. A model predictive type of controller is designed that utilises a set bounded model of the uncertainty and employs safety zones modifying the original constraints so that the control input feasibility can be guaranteed. The controller is applied to quality control in a benchmark Drinking Water Distribution System, and its performance is validated by simulation.