In medium saucepan, combine wild rice and water. Bring to a boil. Reduce heat to low; cover and simmer 50 to 60 minutes or until rice is tender and water is absorbed.
Meanwhile, grease 1 1/2-quart casserole. In large skillet over medium heat, cook bacon until crisp. Remove bacon from skillet; drain on paper towels.
Discard all but 1 tablespoon drippings in skillet. Add onions, celery and carrot; cook and stir 3 to 5 minutes or until tender. Stir in mushrooms; cook and stir 1 to 2 minutes. Stir in soup and bacon.
Heat oven to 350°F. Add cooked rice to skillet; mix well. Spoon into greased casserole; cover. Bake at 350°F. for 30 to 35 minutes or until thoroughly heated.