The city of Raleigh must grow smarter and include some transit system other than roads to help accommodate the region's growth, according to a national public policy expert.

"I cannot see a metropolis succeeding in the 21st century without a state-of-the-art transit system," said Bruce Katz, vice president of the Brookings Institution and an expert in demographic trends and transportation reform.

Despite unsuccessful attempts for a regional commuter rail in the Triangle, Katz believes a rail, along with dense development, is needed for Raleigh's transition into a large 21-century city.

"If you don't change how you are growing, you are going to have a lot of hurt, environmentally and fiscally, down the line," he said.

City-planning leaders realize missed opportunities, and as a result, are updating the city's comprehensive growth plan for the first time in 20 years.

"It's a blueprint of how we want to see ourselves over the next 20 years," Raleigh Planning Director Mitch Silver said. "It will look very carefully at our transportation network, our downtown, density and how we are going to push forward with parks, roadways and schools."

As for a regional commuter rail, the Triangle Transit Authority and other groups are now working on a new regional transit blueprint.

The goal is to identify future corridors along with possible transit modes within each corridor, such as rail, high-occupancy vehicle lanes or bus lanes.

Planners could identify a new corridor as early as this fall