1. Preheat oven to 400°F. Meanwhile, brown ground beef in large nonstick skillet over medium-high heat.
2. Combine sauce and water in large bowl. Stir in browned ground beef, ricotta and Parmesan cheeses, then uncooked ziti. Pour ziti mixture into 13 x 9-inch baking dish. Cover tightly with aluminum foil. Bake 55 minutes.
3. Remove foil and sprinkle with mozzarella cheese. Bake uncovered an additional 5 minutes. Let stand 10 minutes before serving.