When the town of Hamburg faced another potentially devastating flood risk at the end of May, 11 residents took action and raised the levy on their own — protecting a community already struggling to rebound in the aftermath of massive March flooding. Over at NPR, this year’s headlining flood season raised the question: What are these 100-year flood events when some communities seem to experience so many of them? Experts say the probability is difficult to understand, even for educated citizens and elected officials. A 1-in-100-year event has a 1% chance of happening every year — and if a home has a 1% chance that it will flood each year, that means there’s a 26% chance it will flood over the course of a 30-year mortgage. Now researchers and hydrologists are attempting to transition the language of risk away from 1-in-100 or 1-in-500, and instead focus on annual probabilities.