Streams, once neglected, are now seen as assets for urban renewal
The Federal Emergency Management Agency publishes maps outlining 100-year and 500-year flood levels, but Becker said even those maps don’t go far enough. There’s an inherent tension, he said, because people are drawn to water and developers are likely to follow suit.
“And developers love creek land because it’s often cheap,” said Becker, author of “The Creeks Will Rise,” which details how people and creeks can co-exist.
And as communities turn to their streams for redevelopment, these assets come at a price due to the increased risk of extreme weather.
“The past is no longer a prologue,” Mr Becker said, adding that just because a stream hasn’t overflowed beyond its banks doesn’t mean it won’t ever happen.
In Lincoln, Neb., where Salt Creek meanders through the city, developers are considering developing some prime plots of land. Ben Higgins, the city’s recently retired stormwater superintendent, worries about putting too much of a hazard, a sentiment shared by the business community.
Most of the time, Salt Creek is no 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 an inch from sweeping 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 seen several episodes of “50-year floods” over the past 50 years. The one in May 2015, when the creek peaked at 2.28 feet, was considered a 100-year flood.
“Climate change can alter the legal limit of a floodplain,” said Zhenghong Tang, a professor at the University of Nebraska-Lincoln who has worked with the city on city planning and flood control issues. “I think some companies are quite adaptive and think strategically, especially the big national chains, when it comes to building. However, the premises are sometimes not.