In the aftermath of Superstorm Sandy's devastating blow to New York City, Mayor Michael R. Bloomberg (R) called for a special initiative to rebuild a stronger and more resilient city. That would be a smart investment, but the challenge, once again, will come in funding it.

Research has shown that flood- protection infrastructure consistently offers at least $4 of benefit for every dollar spent. The challenge is finding the funds to plan and build defenses rapidly at times when damaged communities have less to invest and the appetite for large public projects is low.

Recent experiences in New Orleans could offer answers—in particular, by showing how policy shifts that encourage public-private collaboration and partnering could help ease the way.

After Hurricane Katrina in 2005, Congress appropriated more than $14 billion for a Hurricane Storm Damage Risk Reduction System. Congress gave the U.S. Army Corps of Engineers only four years to build it.

The Corps addressed that challenge by introducing design and project-delivery innovations that allowed completion of an enormous amount of construction at lower cost and in a fraction of the time usually required for federal civil works. That let families, businesses and local governments take practical steps to relocate, rebuild to suitable standards and restore economic activity.

When Hurricane Isaac struck New Orleans last year, the system prevented damage far in excess of its cost. It paid off in one storm.

Although the full construction costs were federally funded—a scenario unlikely to be repeated—the experience gained still can improve future programs.

Historically, engineers have relied on data from past events to inform design. We now have scientific tools for a forward-looking approach that rigorously assesses anticipated sea-level rise, increased storm intensity and geomorphic changes. Those tools were applied extensively in planning the designs for New Orleans. For communities grappling with risks from climate change, innovative science, engineering, construction and financing, such as public-private partnerships, can facilitate infrastructure projects that make business sense today and far into the future.

Designs developed with science-based foresight were vetted by independent review, plans were shared with stakeholders, and, for the first time in a major Corps civil-works project, design-build delivery was used. Contractors participated in reviews and provided critiques and input that improved quality, cost and schedule.

In the analysis of flood risk, the most extreme flood potential was along the Chalmette Loop Levee in St. Bernard Parish. Improvements now include 23 miles of levees raised 10 to 15 ft, topped by new floodwalls with highway and railroad closures, navigation gates and a pumping station.