The Mall in Columbia, which sits in the very center of this planned community, is not the heart of Columbia, at least according to residents attending a series of planning workshops.

Rather, manmade Lake Kittamaqundi, just beyond the mall's eastern boundary, was the favorite of a group of about 200 who gathered Monday night to craft a new vision for Town Center. But right now, the lake is bypassed by the six-lane Little Patuxent Parkway and walled off by development in and around the mall. Over the next 30 years, some radical surgery may be called for, said planners with Design Collective, Inc., the Baltimore firm leading the week-long planning process known as a charrette.

Much of the charrette is being conducted at the Columbia offices of General Growth Properties Inc., which acquired the Rouse Co. last year. General Growth wants to develop 51.7 acres near Broken Land and Little Patuxent parkways. That's the last large undeveloped parcel in Town Center. In recent months, the company has been working with Howard County officials to take a comprehensive look at Town Center.

"Nothing is cast in stone yet," cautioned Design Collective leader Matthew A. D'Amico. Then he unveiled planners' renderings of the wish lists they collected from residents during the charrette's first workshops.

To create a more varied urban landscape, planners extended new walkways and existing streets such as Twin Rivers Road through mall property. They showed north and south extensions of Wincopin Circle and a longer boardwalk along Lake Kittamaqundi's western shore. They shrunk Little Patuxent Parkway from six to four lanes and added stores and restaurants that faced the road.

"We could really transform the character of Little Patuxent Parkway and make it a livable street," D'Amico said.

One sketch showed 10- and 15-story apartment buildings bordering Symphony Woods and Merriweather Post Pavilion, but some in the audience warned that residents would complain about the loudness of the music at the open air concert venue and that that might lead to the pavilion's closing.

Others in the audience said that Town Center should reach out more to the surrounding neighborhoods.

"This is a west Columbia happening," said Bill Chesnutt, a longtime resident. "You forgot east Columbia. We've got to do something about getting Oakland Mills, Owen Brown and Long Reach into Town Center."

Some residents were critical of proposals to increase density, but others said it was essential to shaping the Town Center's character.

"The Town Center is a natural, obvious solution to our growth in housing in the county," said Clarksville resident and urban planner Tim Sosinski. He added that the county could require General Growth to pay for the right to develop more densely.

"If we're afraid of density, we're going to create a ghost town," he said.

Ben Kleinberg, a resident of the Town Center and retired professor of urban sociology, told planners that their presentations are too sketchy.

"When you're defining a vision, it seems to me you need some specific numbers," he said, calling for more details on the proportion of proposed commercial and residential development.

The planning process continues this week, with a final presentation scheduled for 2 p.m. Saturday at General Growth's Spear Center off Little Patuxent Parkway.