Yes, you can substitute water with milk in pasta recipes. This substitution works well, especially when the recipe calls for a small amount of milk, as the taste difference is not very noticeable. If a richer flavor is desired, you may opt to use half milk and half water instead. Adding butter or olive oil to the cooking liquid will also add flavor if desired. Another option is to use evaporated milk, which adds a slightly creamy texture and flavor without having to add other ingredients. Keep in mind that using water instead of milk does change the overall texture of the dish; it will be less creamy and more al dente than if made with milk.