1. Some residents are returning home in southeast Texas, a week after Harvey began battering a 300-mile stretch of the state.

Many of them found extensive damage, and Gov. Greg Abbott stressed that it will be “a multiyear project for Texas to be able to dig out of this catastrophe.” The White House said it would ask Congress to approve $12 billion as a down payment for disaster relief.

The authorities are urging people to avoid floodwater and take safety precautions. Here are answers to the most common questions about health risks.