The man who led relief operations after hurricane Katrina devastated New Orleans in 2005 is in Winnipeg to give advice on disaster management.

Former mayor Ray Nagin's speech on Wednesday to a conference of emergency management experts will focus on the need to fund and build disaster-prevention infrastructure before storms hit.

He says the Red River Floodway, which diverts rising water around Winnipeg, is a good example of how spending on infrastructure can save billions of dollars in damage.

Nagin also says the U.S. government's response to last week's so-called superstorm Sandy has been much better than the response to Katrina, thanks in part to less political infighting.

The Democrat says the handling of the Katrina crisis was hurt partly by political friction with the Republican administration of George W. Bush.

He also says the Federal Emergency Management Agency, or FEMA, had an inexperienced director back then.

But one of the things he learned from Katrina is that handling the aftermath of a disaster is almost more difficult than the storm itself.

"We want things to happen almost immediately. I think it's the McDonald's effect — you go through a drive-thru and you get your fries and shake in three to five minutes; so we want to see our cities and our areas restored immediately," Nagin said.