New Orleans is moving to become a national model of how a city can embrace green tactics to tame water.

The city once overwhelmed by Hurricane Katrina's floodwaters is recalibrating its old system of drainage canals and pumps by installing green infrastructure projects, potentially on an unprecedented scale for an American city.

New Orleans has received about $249 million in federal funds to turn neighborhoods into green infrastructure experiments, mimicking natural cycles of storing and filtering water rather than flushing out runoff with ditches and pumps. New zoning rules require new large commercial projects to install porous pavement, water-capturing land elements and ponding areas.

Architect Z Smith says the city's success and demise are tied up in whether the city learns to handle water.