Washington —- Mayor Shirley Franklin told a Senate committee Thursday that Atlanta taxpayers and utility customers are reaching their limits in paying to fix the city's "severely neglected infrastructure."

Franklin said Atlanta needs help from the state and federal governments for roads, bridges, mass transit, water treatment and other such projects because residents are already complaining about utility bills.

She said the question she is asked most often is, "Why are water and sewer rates so high?" and right after that comes, "Why didn't the federal government help us more?"

Along with New York City's Michael Bloomberg and other big-city mayors, Franklin testified in support of a proposal to create a National Infrastructure Bank that would base federal funding on merit, rather than the legislative clout that enables senior members of Congress to secure pork-barrel projects.

"The bank would mark the first federal effort to prioritize infrastructure projects across different modes of transportation and of water treatment," said Sen. Chris Dodd (D-Conn.), who co-authored the bipartisan bill with Sen. Chuck Hagel (R-Neb.)

As chairman of the Committee on Banking, Housing and Urban Affairs, Dodd called the hearing to question mayors about their needs on infrastructure.

Dodd said he hopes to mark up the bill in July in his committee and have it on the Senate floor for a vote shortly afterward.

The new bank would raise capital by issuing up to $60 billion in tax credit bonds.

"The bank would give loans, grants or loan guarantees to states and local governments for major infrastructure improvements," Hagel said.

The mayors agreed that such help would be welcomed by their cities.

Franklin said when she took office in 2002, "it did not take me very long to realize that the city's severely neglected infrastructure would require my immediate attention, particularly the rebuilding of our water and sewer infrastructure."

She told the committee that Georgia should raise its gas tax to pay for transportation and other infrastructure needs.

She noted that the state's gas tax of 18.5 cents a gallon is among the lowest in the nation.

Kansas City, Mo., Mayor Mark Funkhouser agreed with Franklin that gas taxes should be raised. Jacksonville Mayor John Peyton said it isn't politically feasible with gas selling at $4 a gallon. Bloomberg left the hearing before the gas tax was discussed.

Because the $4 billion Clean Water Atlanta Initiative has so marked her administration, Franklin said she has become known as the "Sewer Mayor."

On the need for improving the infrastructure, she said, "The bottom line is that the cost is greater than our city can bear long-term."

She said the court-ordered water and sewer project has built more than 120 miles of new water mains, reduced sewer overflows, separated sewers except in downtown, inspected more than 1,000 miles of sewers and rehabbed about 250 miles of sewers.

As a result, she said, "one of our primary waterways —- the Chattahoochee River —- is cleaner than it was 10 years ago."

The cost has been borne "largely on the backs of the city's residents, some 25 percent of whom live at or below the poverty line," she told the committee.

—- D.L. Bennett contributed to this article.