In small saucepan, heat broth and water over medium-low heat; let simmer. In large saucepan, heat oil over medium-high heat. Add onion and peppers to pan, and cook 4 minutes, stirring. Add sausage and cook 2 minutes to brown. Stir in zucchini slices, garlic, and oregano; cook 4 minutes. Transfer vegetable-sausage mixture to bowl.
Stir rice into large saucepan, and cook 1 to 2 minutes, or until lightly toasted. Add warm broth, 1/2 cup at a time, stirring frequently with wooden spoon and waiting until liquid is absorbed before adding more (this will take about 20 minutes).
Stir in vegetable-sausage mixture and Parmesan. Cook to warm through. Serve immediately.