By Steve Tawa

PHILADELPHIA (CBS) — Mayors from cities large and small have gathered in Philadelphia to put pressure on Washington to invest in cities.

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Dozens of mayors surrounded their host, Michael Nutter — the leader of the US Conference of Mayors (at lectern in photo) — to discuss their national agenda for cities.

The Conference of Mayors wants to use its clout to get Congress to invest in our infrastructure.

Mayor Scott Smith of Mesa, Ariz., recalled previous generations that represented his grandparents and great-grandparents.

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“They invested in their cities,” he said.  “They invested in sewer and water systems, roads, ports, rails, and airports, so we could benefit today from the economic prosperity that we enjoy.”

Baltimore mayor Stephanie Rawlings-Blake notes that as she was leaving that city to come to the conference, it was dealing with a major downtown water main break.

“To me, it’s just as much a homeland security issue as the wars we fought,” she said today.  “This is potable drinking water!  And making sure our cities continue to function.”

The mayors released an economic report that shows public spending on infrastructure in the US is only 2.4% of the gross domestic product.  Europe invests 5% of GDP, and China 9%, on infrastructure spending.

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