Why do today what you can put off until tomorrow? That saying resonates with many of us; we’re a species that likes to procrastinate. But there may be more wisdom in the old adage, “a stitch in time saves nine.”

It might seem like common sense that prevention is better than trying to fix problems after they happen, but a new study published in Proceedings of the National Academy of Sciences has quantified just how much better it can be when it comes to flooding — particularly the increased flooding we can expect as sea levels continue to rise.

The researchers found that it’s more cost effective for most coastal area economies to use flood prevention strategies — including green strategies like buffer islands — than it is to repair damages after a flood. “The global costs of protecting the coast with dikes are significant with annual investment and maintenance costs of U.S. $12–71 billion in 2100, but much smaller than the global cost of avoided damages,” which vary by area. Climate change-fueled sea level rise is coming, they say, and we must adapt, not wait and see where the cards fall. And there is a lot at stake here. It is estimated that as many as 1 billion people currently live in at-risk areas.

The study addresses both grey and green flood prevention infrastructure — grey such as levees and green such as coastal forests and wetlands. Last year, another report showed us just how many Americans these coastal buffers are protecting. Taken together, these studies say a lot about the benefits and potential benefits of our hardworking coastal buffers. It’s why many of our American Forests Global ReLeaf projects are working to protect buffers like wetlands and mangroves.