MIAMI—All roads lead to and through Miami. That was the theme of an event the Commercial Industrial Association of South Florida (CIASF) and CBRE Global Investors just held in Miami.

Tom Hudson, host and producer of WLRN's "The Sunshine Economy," moderated a panel that included Esteban Bovo Jr.,  Miami Dade County Commissioner (District 13); Oscar Gonzalez, Project Public Information Specialist for the 826/835 Expansion Project (Palmetto & Dolphin Expressways); and Ken Roberts, CEO of World City Magazine. Ultimately, there was a lot of talk about planes, trains and automobiles.

Gregory Owens, assistant director of Business Retention and Development for the Miami-Dade Aviation Department (MDAD), kicked off the discussion by laying out how Miami International Airport, or MIA, stacks up against other airports. Beyond ranking as the number one airport in the US for international freight and second for international passengers, MIA is the only airline in the US with over 100 airlines. (There are 102 to be exact).

What's more, MIA rose from 12th to 10th place this year for total passengers, with 43.3 million passengers in 2015 so far, according to MDAD. The department has overseen $6 billion in capital improvements to the airport.

"Everything happens around MIA—it's a real driver for the economy," said Roberts, whose Miami-based media and event company focuses on the role of globalization on local communities. His firm is tracking 1,400 multinationals from 55 nations around the world that are based in South Florida and contribute to the city's robust trade.

Although slightly down from previous years, trade through MIA totaled $39.93 billion through first nine months of 2015. He anticipates more trade in the future between Miami and Asia and Latin America.

More business means more traffic, which is why the $560 million dollar expansion of the Dolphin and Palmetto expressways, and creation of a four-level interchange, was necessary to keep commerce moving—literally—around the airport, according to Gonzalez. The interchange handles about 430,000 vehicle trips each day. The 826/836 project, which began in 2009 and wraps up in May next year, will enhance safety, increase capacity and make the roadways more efficient for motorists.

But the city's underdeveloped public transportation remains Miami's biggest hurdle to economic growth, said Bovo, who estimated gridlock is costing families between $3,000 and $4,000 per year in gas, parking and maintenance. "Your employees cannot be productive if they are stuck in traffic," he said. However, he added, "I can safely say you will never see another expansion of Metrorail unless somebody rains a lot of money on us."

Bovo, who chairs the commission's Transportation Committee, is advocating a plan to acquire a 11-mile segment of CSX railroad track that parallels the Dolphin Expressway, delivering the promised east-to-west commuter line voters thought they would get when they approved a dedicated tax back in 2002. He estimates the cost of constructing a commuter rail on 11 miles of CSX line to be about $100 million – about the cost of constructing just one new mile on the Metrorail.

Still, he acknowledges that the voters won't give the County any more money, which is why he is seeking state support to make it happen: "The hope is to create a mechanism … for public/private partnerships to develop the stations."

Bovo also issued a call to action to the 100 plus business professionals in the room: "We need corporate Miami involved in the discussion [about public transportation]. They've been absent a long time."