The document helps the corps decide how much water should be released or retained at any given time in each of the ACF system’s five reservoirs. It needs to be revised so that it reflects current conditions, such as drought and population growth.

Jim and Brenda Duggan, who bought a home on Lanier in 2004, came to the meeting looking for answers from the corps.

"We wanted to know what is their logic (for releasing water from Buford Dam)," said Jim Duggan. "And I want a better understanding of what the mission statement is for control of this basin."

The open-house meeting began at 5 p.m. at the Georgia Mountains Center, and by 6:30, more than 350 people had registered.

The Gainesville meeting was the last of five; others were held last week in Apalachicola, Fla.; Dothan, Ala.; LaGrange; and Marietta.

Pat Robbins, spokesman for the corps, said there has been intense interest throughout the ACF basin.

"We’re seeing a lot of participation, a lot more people submitting comments than at meetings in the past," he said.

A dozen laptops were set up at the meeting so people could type in their comments online, and the computers were occupied most of the time. A court reporter was also available to take verbal comments.

Those who could not attend one of the meetings can still submit comments online or by mail until Nov. 21.

Brenda Duggan said she planned to comment later, after she had time to think about what she wanted to say.

"We don’t know enough. That’s why we’re here today," she said.

Many people attending the meeting wanted to learn more about the endangered mussels in Florida’s Apalachicola Bay, which the corps has cited as a reason for letting more water flow downstream on the Chattahoochee River. But Brenda Duggan had a different concern.

"A lot of us feel that this water is being released to flush out the city of Atlanta," she said. "Why aren’t we taking into account the problems with Atlanta’s sewer infrastructure? You don’t really hear much about that."

The corps has to maintain a certain amount of flow in the Chattahoochee River at Peachtree Creek in order to dilute Atlanta’s wastewater discharges.

Robbins said all of the comments collected at the public meetings will be considered as the corps writes a draft environmental impact statement and a draft water control manual.

"Both of those documents should be ready in spring 2010," he said. "But our time frame could slip if there’s no funding. Our budget has to be authorized by Congress year by year."

At the open house, booths were set up addressing topics such as socioeconomics, environmental resources, and water management. Officials from the corps and its consulting firm Tetra Tech were available to answer questions.

But for the first hour of the meeting, the exhibit room was so crowded that people could barely move, and they had trouble even getting close enough to the tables to ask their questions. Some just picked up handout sheets to read at home.

"I’m not sure how useful this kind of format is," said Darcie Holcomb, director of headwaters conservation for the Upper Chattahoochee Riverkeeper in Gainesville. "It’s really crowded and loud and it’s hard for people to talk. I don’t know if they’re able to absorb all this information."