From Marietta to McDonough to Cumming, communities across the Atlanta region differ wildly in how much they consider their growth's impact on an increasingly precious resource: water.

[ Post your comments below. ]

Phil Skinner/AJC (ENLARGE)

Construction continues on a $100 million, 5.7 billion gallon reservoir that will serve the region's projected population growth and prepare for the next drought. The reservoir is being built by the Cobb County-Marietta Water Authority and the city of Canton.

PEOPLE KEEP FLOWING IN • Georgia is one of the most rapidly growing states — with population rising from 8.2 million in 2000 to 9.4 million in 2006, it is the third fastest-growing state in the nation. • In 2000, Fulton, Gwinnett, DeKalb and Cobb counties were home to more than half of metro Atlanta's population and have a combined public water supply withdrawal rate of about 438 million gallons per day. That was about 168 gallons daily per capita withdrawn for residential, commercial, and municipal uses. • Even though Georgia's high annual rainfalls — average 51 inches per year — are usually enough to recharge the aquifers from which residents get most of their water, the combination of recent droughts and ever-growing demand have strained groundwater resources across the state. • If every household in Georgia installed WaterSense labeled faucets or aerators, it would save more than 5 million gallons per day, which would fill every tank in Atlanta's Georgia Aquarium in just a day and a half. — Sources: U.S. Census; U.S. Geological Survey, 2000; U.S. EPA • Photos: A shallow Lake Lanier can be hazardous DEALING WITH THE DROUGHT: • Can I water? Here are the rules • 10 tips to save water • Map: Heavy demands on our water RELATED: State tries again to reduce Lake Lanier outflow  Atlanta area gets about an inch of rain  Rain predicted for Wednesday, just not as much  Rain coming! Look for it Tuesday night, Wednesday  Georgia drought persists, but not panic  • More on coping with the drought

In Cobb and Gwinnett counties, for example, officials considering building requests don't require developers to report how much water their projects will use.

In contrast, DeKalb and Henry county officials say they won't approve a new development unless there is enough water to serve it. But in DeKalb, officials are just now preparing to draft the first 25-year water infrastructure plan for their county — to include preparations for a drought.

In Forsyth County, officials have imposed a months-long moratorium on residential rezonings, partly to give them time to assess how much stress growth has put on the water supply. Fulton County sits somewhere among all these communities, giving water use some weight in building approvals.

This spectrum underscores how the Atlanta area lacks a single, unified approach to managing growth, even as it grapples with a dwindling water supply that has spawned a ban on outdoor watering, hefty fines for water hogs and legal showdowns between state and federal officials over Lake Lanier.

State law outlines which factors local planning departments should consider in considering rezoning requests for development. It says those factors should include whether projects could cause "burdensome use of existing streets, transportation facilities, utilities or schools."

That law, approved in 1985, applies only to Atlanta and Fulton and DeKalb counties, but other Georgia cities and counties are free to adopt those standards and reject proposed developments if they determine there is not enough water supply, said Frank E. Jenkins III, a Cartersville zoning attorney who helped write the law.

An official at the Association County Commissioners of Georgia said he has not heard of any Georgia counties rejecting a rezoning based solely on concerns over water.

"We don't have any counties out there that are innovative enough and have written a zoning classification that is tight enough to really make a decision based solely off of water supply," said Kem Kimbrough, the association's assistant general counsel.

Meanwhile, the Atlanta area's population has kept growing — and so has its demand for water. Georgia's municipal water use jumped by 29 percent between 1990 and 2000 as its population grew by 26 percent, according to the U.S. Geological Survey. (More recent statistics were not available.)

Not everyone in the region agrees that growth is a major factor in the state's water crisis. Environmentalists blame unchecked development. Homebuilders blame the environmentalists for blocking public water infrastructure. And the politicians and planners — who say they are hamstrung by property-rights and state zoning laws — blame the U.S. Army Corps of Engineers for releasing too much water from Lake Lanier to protect endangered mussels and support a power plant downstream in Florida.

"The elephant in the room that nobody is talking about is overdevelopment in metro Atlanta and the way we have developed for decades, which has resulted in very wasteful use of our water," said Sally Bethea, executive director of the Upper Chattahoochee Riverkeeper, a water-protection organization. "The attitude we have seen is basically unrestricted water for unrestricted growth."

Bethea and other environmentalists say local governments in the Atlanta area need to tighten restrictions on developers, including making them disclose in advance how much water their projects will require.

Homebuilders say environmentalists are to blame for the state's water woes by fighting the construction of new water reservoirs and treatment plants in Georgia.

"The term is deflection. That is what the environmental community is trying to do right now because they don't want to accept responsibility for what they have done in the past," said Ed Phillips, executive vice president of the Home Builders Association of Georgia, which represents more than 13,000 builders.

With an eye toward these concerns, a state-mandated planning body issued a water supply plan for metro Atlanta in 2003. It broke down what percentage of available water each local jurisdiction could expect long term, said Joel Cowan, the founding chairman of the body, the Metropolitan North Georgia Water Planning District.

Cowan said he expected each community to set development controls that would let them live within their water allotments. Instead, he said, "So far as I know, that has not been done. And I think that is a failing."

Without limits, the people who develop first will get dibs on all the available water and leave other land owners unable to develop, Cowan said. "I think we are building ourselves into a severe hole," he said

Wayne Hill, a former member of the same planning body and former chairman of the Gwinnett County Board of Commissioners, said he doesn't think such limits on development are realistic or right.

"We still live in a free country," said Hill, whose county is one of the fastest growing in the nation. "I don't think that was ever a thing we put out there and said, 'Limit the population.' "

Sam Olens, chairman of Atlanta Regional Commission and the Cobb County Board of Commissioners, has legal concerns about rejecting rezonings based on water supply.

"I don't really want that multimillion-dollar liability that could follow," Olens said. "I would much prefer to have a statute or a prior case on point telling me I was on a strong legal ground."

The Cobb County-Marietta Water Authority and the city of Canton are now building a $100 million, 5.7 billion gallon water reservoir in Canton to keep up with projected growth and prepare for the next drought.

Olens agreed growth has had an impact on the region's water supply. But like other local officials, he is targeting the federal government for releasing too much water from Lake Lanier, even referencing Hurricane Katrina in connection with the Atlanta region's "impending disaster."

"It would be a crime," Olens wrote in an opinion piece for The Atlanta Journal-Constitution Tuesday, "for our president and the two federal agencies involved to be fully aware, this time, of such an impending disaster for yet another major American city this decade — and just sit by and watch it happen."

But federal officials say the region's rapid growth is an undeniable factor.

"The combination of recent droughts and ever-growing demand," said Enesta Jones, a spokeswoman for the U.S. Environmental Protection Agency, "have strained groundwater resources across the state."

— Staff writers Nancy Badertscher and Matt Kempner contributed to this article.