What is the lake?

The nameless lake is a strong, dangerous presence throughout the book. It always threatens to take back the town. The spectacular derailment off the railroad bridge into the lake claims the most victims. Early in the book it floods the whole town and sends four inches of water into the house, and strands Ruth, Lucille, and Sylvie in the upstairs bedrooms for a week. In winter when it freezes, the townspeople go out on the banks to celebrate, but the lake is never free from danger. Sylvie says, "the lake is full of dead people", and it has killed at least two of Ruth's immediate relatives, her grandfather who dies in the train derailment and her mother, who drives off a cliff into the lake, killing herself.