The Federal Emergency Management Agency publishes maps outlining 100-year and 500-year flood levels, but Mr. Becker said even those maps did not go far enough. There is an inherent tension, he said, because people are drawn to water, and developers are likely to follow.
“And developers love the creek land because it is often low priced,” said Mr. Becker, author of “The Creeks Will Rise,” which details how people and streams can coexist.
And as communities turn toward their creeks for redevelopment, those assets come with a price because of the increased risk of extreme weather.
“Past isn’t prologue anymore,” Mr. Becker said, adding that just because a stream has not flooded beyond its banks does not mean that it will not happen one day.
In Lincoln, Neb., where Salt Creek meanders through the city, developers are considering some prime parcels of land for development. Ben Higgins, the city’s recently retired superintendent of storm water, worries about putting too much in harm’s way, a sentiment echoed by the business community.
Most days, Salt Creek is not more than two feet deep in most places. But in May 2015, a thunderstorm over the Salt Creek basin sent it to near-record levels and within an inch of sweeping away a pedestrian bridge. Lincoln built a series of levees in the 1960s to protect the city from a 50-year flood, but Salt Creek has had several bouts of “50-year-floods” in the last 50 years. The one in May 2015, when the creek crested at 2.28 feet, was considered a 100-year flood.
“Climate change may change the legal boundary of a flood plain,” said Zhenghong Tang, a professor at the University of Nebraska-Lincoln who has worked with the city on urban planning and flood control issues. “I think some companies are pretty adaptive and strategically thinking, especially the big national chains, when it comes to building. Still, local ones sometimes aren’t.”