A study calls for new runways and other expansions at two of the three main airports serving the New York region, where airline delays and cancellations frequently wreak chaos on air travel throughout the United States.
But the report released this week by the Regional Plan Association, an advocacy group, also warns of major obstacles, including environmental laws and development that has eaten up land around the airports.
It offered four options to expand Kennedy airport, each calling for one or two new runways. Three of the four options would require filling in parts of Jamaica Bay, a part of the federally protected Gateway National Recreational Area.
The federal law that created the recreational area specifically prohibits the airport from extending its runways into the bay. The U.S. Congress would have to amend the law to allow construction.
At New Jersey's Newark Liberty International Airport, the association recommended building a third north-south runway. That would require demolishing one terminal and parts of two others.
"Choosing inaction will result in an economic drain on the region," the report said. "It will discourage business, limit visits and prevent our region from fully participating in the global economy."
Costs for the expansion plans range from $1 billion and $3.5 billion each, the report said. There is no room for expansion at LaGuardia airport, the third of New York's Big Three airports, it concluded.
The Port Authority of New York and New Jersey operates all three airports, along with Teterboro airport in New Jersey and Stewart International in Newburgh, N.Y.
The Port Authority provided most of the funding for the study. On Friday it said it was examining the proposals.
"The Port Authority continues to develop new ways to make our airport system the best and most efficient in the country," it said in a written statement.
New York's airports have struggled to keep up with passenger demand in recent years. In 2008 the Federal Aviation Administration imposed limits on flights in an effort to minimize delays, but in November a government report warned the limits were too generous.
The problems were underscored on Dec. 26, when a blizzard forced airlines to cancel thousands of flights over three days at the New York airports. The cancellations tangled up air travel across the United States.
Air travel through New York will rise from 104 million passengers in 2010 to 150 million by the 2030s, the Regional Plan Association report said.
A new air traffic control system being built by the FAA will increase capacity slightly by allowing planes to make tighter turns and fly more direct routes to runways, the report said. But the region still needs more runways if it is to keep up with passenger demand.
It said there were no sites in the New York area suitable for building a fourth major airport.