Current graphical techniques for design of water networks based on pinch analysis typically separate targeting from network design stage. In addition, most graphical allocation and network design tools that use the cleanest source to satisfy the cleanest demand fail when the flow rate of a demand is met but the mass load is not. This work presents a versatile and generic approach for simultaneous targeting and design of water networks. It includes new heuristics and significant new insights on source and demand allocation composite curves, and it introduces a new visualization tool known as the network allocation diagram (NAD). This approach can generate targets for cases with both flow-rate and mass-load constraints and simultaneously solve complex design problems involving multiple pinches. NAD also allows designers to graphically visualize, explore, evolve, and systematically choose networks that yield either the minimum water targets or the minimum number of streams.