Cook bacon in a 10-inch heavy skillet over moderate heat, stirring frequently, until crisp, about 5 minutes. Transfer bacon with a slotted spoon to paper towels to drain, then add butter to fat in skillet and melt over moderate heat.
Add corn, lima beans, bell pepper, and white and pale green parts of scallions and cook, stirring, 2 minutes.
Add cream, water, salt, and pepper, then simmer, partially covered, until vegetables are tender, 10 to 15 minutes
Stir in bacon, scallion greens, and salt and pepper to taste.