Rob Hunter is an engineer by trade, but the man in charge of Atlanta's water and sewer system has a major sales job in front of him next week.

Atlanta's Watershed Management commissioner and a team of attorneys will try to persuade a federal judge on Wednesday to give the city more time -- another 15 years past the current 2014 deadline -- to complete a $4 billion overhaul of its sewer system.

Some South Georgia leaders, who've seen their share of pollution in their waters, courtesy of Atlanta, say no way to an extension.

"In 15 years, they'll be asking for another extension," LaGrange Mayor Jeff Lukken said. "Atlanta needs to step up and do the right thing."

Early this decade, Atlanta embarked on an aggressive and expensive effort to straighten out its antiquated sewer system and improve water quality. Citizens took the unique step of voting for a sales tax to help pay for the work. Sewers became as sexy a subject as sewers can become. City officials boast that Atlanta added $17 billion of new development in the past decade, much of which they say wouldn't have happened if the city hadn't improved its water infrastructure. Some worry an extension will slow that momentum.

Hunter argues an extension is necessary because the city is receiving less money to pay for the work. Noting that Atlantans will soon have the highest water and sewer bills in the nation, Hunter says the city doesn't want to charge homeowners even more. One-quarter of Atlantans live below the poverty level.

"It's a high financial burden," Hunter said in an interview.

Atlanta wants to focus on finishing some major projects, such as completing the South River Tunnel. Some sewer rehabilitation work would take longer to complete, the commissioner has said.

The city's watershed department is at a watershed moment financially.Officials project revenue will fall $52.1 million below what they anticipated in the 12-month period ending June 30. And the department is spending slightly more than $200 million a year -- about 40 percent of its general budget -- to pay off its debts.

Its bond ratings, which are used to determine loan interest rates, are just above junk status. One bond agency, Fitch, told the city in October it is worried about the department's rising debt levels and would monitor its progress closely. Hunter's staff, then-Mayor Shirley Franklin and others first began detailed discussions last year about requesting an extension. The paperwork was filed last week.

Lukken and others say they are sensitive to Atlanta's plight, but there are limits to their empathy. Atlanta has done a better job of stopping pollution from flowing to West Point Lake, they say, but the mayor said his city still sees hypodermic needles, road signs and other trash that he says flows from the Chattahoochee River.

LaGrange, the mayor said, spent around $40 million about two decades ago to improve its own sewer system and to stop polluting waterways farther south. The city, he said, is still paying off the bond debt.

"It was a ton of money for our small community to do," said Lukken, whose city has a population of about 28,000. "We expect no less from everyone upstream from us."

Atlanta's century-old sewer system was designed to carry a mixture of raw sewage, rainwater and polluted streams through pipes buried underground. It's a system designed like other big cities.

Until the mid-1980s, any amount of rain would send untreated wastewater, along with toilet paper and other materials into streams and eventually to the Chattahoochee and South rivers.

While many other cities began fixing dilapidated systems in the 1970s, Atlanta did not react until it was sued in 1995 by Upper Chattahoochee Riverkeeper group, along with a coalition of downstream counties and cities.

At one point in the 1990s, the city was paying as much as $7 million a year in pollution fines. In recent years, the annual fine total has typically been below $100,000.

In 2002, Franklin, then in her first year as mayor, pushed for a 1 percent sales tax, significant rate increases on its customers and more financial help from federal and state officials to fund an overhaul of the sewer system and improve water quality. Proudly, Franklin became known as "the sewer mayor."

Atlanta, the former mayor wrote in an e-mail to The Atlanta Journal-Constitution, became known "as a city committed to improving its infrastructure and making the hard decisions required to meet current federal standards."

City leaders hope they have earned the benefit of the doubt for the extension by underscoring the generally good reviews Atlanta has received from Thomas Thrash, the judge monitoring the consent decree.

"I trust the last seven years of performance by [Watershed Management], the commissioner, the commitment of [the City Council], my administration and the public will add advantage in the city's appeal to the court," Franklin wrote.

EPA officials said most consent decrees in similarly sized Southern cities cover 10 to 15 years. An EPA spokeswoman said the agency has worked with cities when they’ve had trouble financing the costs to meet the decree guidelines.

Federal and state environmental protection officials agree the work has generally been done on time. They say they need more time to review the city's detailed 125-page extension request before responding to the request.

Joe Maltese, who works on water resource issues for LaGrange and other neighboring communities, said he's concerned about the extension request. Fifteen years past the current deadline seems to be too much time, he said.

"We don't want to see harm to Atlanta, but gee whiz," Maltese said.

Sally Bethea, executive director of the Upper Chattahoochee Riverkeeper, said she has spoken with city officials in recent months about the extension request. She wants to make sure the major work is done before 2014.

"We just want to make sure the job gets done and there's some relief for rate payers," she said.