A marsh fire in the Bayou Sauvage National Wildlife Refuge in New Orleans East continued to burn on Tuesday, spewing smoke over the New Orleans area, while city officials surveyed the fire and stuck to a plan to allow it to burn itself out.

Mayor Mitch Landrieu flew above the fire in a helicopter Tuesday morning and reiterated that dousing it from planes or helicopters would have little effect on the large, mostly underground fire.

The Louisiana Department of Environmental Quality issued an air quality precaution day, because smoke from the fire continued to pose a health hazard to people with lung and heart problems, children and the elderly. The DEQ also recommended that everyone avoid exertion and prolonged exposure to the smell.

From the Westbank to New Orleans East, Metairie to the Warehouse District, smoke hung over the New Orleans area, sometimes limiting visibility to less than half of a mile. The haze obscured the tops of downtown skyscrapers for much of the morning.

City and state officials said the smoke was merely a nuisance to healthy people but urged anyone experiencing symptoms to seek medical help.

Weather forecasts called for rain on Thursday, which Landrieu and New Orleans Fire Department Superintendent Charles Parent said Monday they hoped would help extinguish the fire.

For information about air quality and for air quality forecasts, go to http://www.deq.louisiana.gov/portal/tabid/2505/Default.aspx

Citizens who want to report environmental concerns may call the DEQ at 225-219-3640 or 888-763-5424.

To sign up for air quality alerts, go to www.deq.louisiana.gov/enviroflash.