The campaign to get Atlanta voters to OK a 1 percent sales tax for sewer projects got a boost of $50,000 in seed money from Mayor Kasim Reed's 2010 inaugural committee, according to a report filed with the state ethics commission.

Three weeks before Tuesday's vote, the inaugural committee, a nonprofit corporation, made a loan to Citizens for Clean Water 2012, a private advocacy group set up to get the municipal option sales tax reauthorized for another four years. The tax originally was approved in 2004 and renewed in 2008.

The contribution from Reed's inaugural committee was the only one listed in a February filing with the ethics commission. But the private campaign has raised more than $400,000 since the filing period, Reed told The Atlanta Journal-Constitution. The identities of the more recent donors should appear in future disclosures.

Atlanta leaders -- including Reed, members of the City Council and officials with the city's watershed department -- have said the tax is necessary to keep Atlanta's already high water and sewer bills from jumping as much as 30 percent. An Atlanta family using 6,000 gallons per month, considered average, spends $150 on water and sewer bills.

State law and Atlanta's code put limits on what local officials can do in support or opposition to taxes such as the MOST. Rick Thompson, former director of Georgia's ethics commission, said state law restricts public officers or agencies from making contributions to a campaign.

But when it comes to elected officials advocating for major initiatives, Thompson said the commission did not find a violation during his five-year tenure.

"As long as they weren't using city money or city resources" such as copiers, he said, there is leeway to advocate.

Reed said he kept his advocacy work separate from his work as mayor. He made fund-raising calls from a private office, rather than from City Hall. Outside legal counsel told him his inaugural committee could contribute cash to the sewer effort, but his campaign could not.

Citizens for Clean Water 2012 is chaired by former Atlanta Mayor Andrew Young. Attorney Robert Highsmith, an associate of Reed at the law firm Holland & Knight, serves as treasurer. Jan Prisby Bryson, an Atlantan who worked on the 2008 renewal campaign for the MOST, is coordinating the effort.

A document filed electronically Feb. 24 shows only two expenditures from the campaign to that point: $30,000 to polling group Anzalone Liszt Research of Montgomery and $5,000 to the Campaign Group Inc., a Philadelphia-based media firm. That left $15,000 in cash on hand and $50,000 in debt.

Mailings from Citizens for Clean Water 2012 show Reed standing in front of City Hall, arms crossed, striking a serious pose in support of the tax extension. He has been in radio ads, in televised public service announcements and has done a range of media interviews.

"We can use city resources to educate, but not to encourage a ‘yes' vote," Reed said. "On the private side, I can express my opinion. And I did."

Reed has called the timing of the vote, coinciding with Tuesday's hotly contested Republican primary, a concern for backers of the tax.

"Fortunately, we are working on it," he said in February. "We already know from the early results that Republican voters do not want their water bills to go up."

The ballot language is another concern for backers of the tax. The ballot question indicates that renewing the tax could raise up to $750 million for water and sewer projects and costs. But city officials say the tax would need eight more years -- with another reauthorization in 2016 -- to actually hit that number.

Over the next four years -- the period in question Tuesday -- the tax will yield between $400 million and $440 million, according to the city's estimates.