As she delicately unfurled her poster-size map of New Haven on the committee room table Thursday night, Donna Hall slowly shifted her weight from her left foot to her right and then stared sheepishly at the pack of 10 anxious men and women standing across from her.

A few seconds later, the map finally open before her, Hall — a senior project manager with the City Plan Department — was ready for the deluge.

Because the city could not find an outside consultant willing to take on the task, Hall and co-worker Roland Lemar have been assigned to help a Board of Aldermen special committee redraw the city’s ward districts. Using geographical information systems computer software and the results of the 2000 Census, Hall and Lemar had prepared a map showing how the committee might choose to redraw the 30 wards.

The reason for Hall’s nervousness Thursday soon became obvious: Like sharks in a feeding frenzy, the aldermen descended on the sheet of lines and colors, each examining his or her new ward to see how drastically it had changed.

Ward 25 Alderwoman Nancy Ahern, the committee’s sole Republican, pointed a shaking finger at her redrawn ward, which now straddled a river and bisected a park.

“This map just doesn’t take into account any topographical elements,” she said, explaining how the proposal would make it more difficult for her constituents to get to their polling places.

Ward 13 Alderwoman Rosa Santana, who is not actually a member of the committee but attended the meeting to see how her constituents would fare, was nervous about how the changes would affect one of her ward’s Hispanic communities.

Carl Goldfield, Ward 29 alderman and the committee’s vice chairman, finally intervened.

“Everyone needs to stop and speak one at a time,” he said, raising his voice above the din. “Otherwise we’re going to end up with this cacophony again.”

Hall, Lemar, Goldfield and the 10 other aldermen are faced with a difficult task. Without significantly altering each ward’s current racial and ethnic makeup, the committee must create 30 new wards of roughly equal population that do not cross the boundaries of newly redrawn state assembly districts.

Between 1990 and 2000, New Haven’s population dropped by 6,848, but several internal population shifts within the city mean some wards will grow in size while others shrink.

Hall and Lemar thought the map they presented was a good starting point. None of the new wards they had created varied more than 4 percent from the population of any other.

But somehow, wards of roughly equal population did not seem to satisfy the legislators.

For the two city planners, this was a lesson in politics: What seems right on paper may not pacify 11 different legislators who answer to different constituencies.

As Board of Aldermen President Jorge Perez, D-5, put it, not everyone would be satisfied once the process was over.

“People need to keep in mind that we have 30 wards and that at the end of the process, we’re still going to have 30 wards,” he said. “But at the end of it, no one is going to be happy.”