As Hurricane Helene slammed into the U.S. last weekend, causing an estimated $225 billion in damages, a critical gap in U.S. preparedness for weather disasters was exposed: Americans’ dangerously low levels of flood insurance coverage.

According to the Federal Emergency Management Agency (FEMA), about 4% of people in the United States have flood insurance. Louisiana has the highest adoption rate at 27%; Utah has the lowest at just 0.3%.

The gap between coverage and the risk it is intended to mitigate is widening, especially as climate change leads to more intense rainfall. Every US state is now affected by flooding, including California, Kentucky, Connecticut, Maryland and Vermont in recent years. Even Utah did not experience flooding until August.

“People just don’t believe something like this is going to happen to them,” said Richard Folkman, vice president of claims management firm Crawford & Company. “Even the people who have insurance would say, ‘I just never thought we’d ever see a flood.'”

Insurance literacy is part of the problem, says Talley Burley, director of climate risk and insurance at the nonprofit Environmental Defense Fund. Many people do not realize that flooding is not covered by home insurance. Burley calls flood insurance “the most important tool people can have to help repair and rebuild after a flood event.”

How much do you know about flood insurance? And if you don’t have it yet, should you? Take our quiz and find out.