The River Waal has brought trade and wealth to 2,008-year-old Nijmegen, the most ancient city in the Netherlands. But it also presents danger: Nijmegen sits at a flood-prone river bend that is one of the narrowest in the nation. In 1995, tens of thousands of residents were forced to evacuate after heavy rain and snow upstream in the Alps swelled the Waal.
Scientists and engineers want to mitigate the danger of the Waal's narrowness at Nijmegen, create more capacity for the river, and ultimately lower the water level by just over 1 foot.
An existing dike will be demolished. A 2.5-mile-long, 650-foot-wide side channel for the river is being dug. A new dike will be built further inland. A new island will be created in the Waal. Cost: $470 million.
The side channel will be an essential spillway in times of high water. Most of the new island will be set aside as parkland and nature preserve. There will also be new housing and commercial development.
Half of the 100 families in the zone must move, and centuries-old homes will be knocked down. Lost wildlife habitat will be replaced. A new pond was dug and a newt population relocated.
A version of this article appeared in the November 2013 issue of Fast Company magazine.