How is flood related to maslow's hierarchy of needs?
how do the people relate?

Explanation:

First we need to see what exactly Maslow's Hierarchy of Needs is, what it stands for and what things it cover.

According to Maslow's Need of hierarchy, humans have the following needs;

Physiological Needs: Basic biological needs, like air, water, food, shelter, clothing, primary health needs etc

Safety Needs: Need of personal security, property, resources etc

Need of Belonging: Having friends, family, people to talk to with etc

Esteem Needs: Need for self respect, freedom, status, recognition etc.

Self-actualization Need: Reaching the heights where one can go and attaining the most highest form of something which one desires.

After reading all the above needs, it is very much clear in understanding that if whenever flood comes, people's foremost priority will be their own survival, after saving their own life first, followed by the securing things needed to continue life like food, water clothing etc, they will start moving towards saving other people life, rescuing them and proving them the facilities they have saved for themselves. That's how people will prioritize their moves and actions according to Maslow's Need of Hierarchy.