In a large bowl, combine the first five ingredients. In another bowl, combine egg, orange juice, water, butter and orange peel. Add to dry ingredients just until combined. Fold in the blueberries.
Pour into a greased and floured 8-in. x 4-in. x 2-in. loaf pan. Bake at 350 degrees F (175 C) for 65-70 minutes or until a toothpick inserted near the center comes out clean.
Cool for 10 minutes; remove from pan to a wire rack.