Mayor Charlie Hales' famously small cadre of senior staffers—meant as something of a fiscal symbol and political rebuke of Sam Adams—will find itself even smaller come Monday morning, the Mercury has learned.

Noah Siegel, one of Hales' handful of policy directors, is leaving to take a regional infrastructure policy and planning post with Metro. Siegel, though technically the mayor's liaison to the Office of Neighborhood Involvement, is best described as something of a "fixer" for Hales and chief of staff Gail Shibley. His name has been attached to the city's arts tax, hard-fought negotiations with the firefighters union, and issues involving water and sewer rates.

Siegel confirmed his departure in a brief interview this afternoon and said it was in the works for a couple of weeks.

"All the fun stuff," he said. "That seemed to be my role."

It's potentially a big loss. Siegel's also one of the most experienced staffers in Hales' office, at least in terms of the sometimes tricky political ecosystem of Portland City Hall. Before signing on to work in Hales' office, Siegel spent nearly four years as Adams' director of international affairs. Translated, that meant he played point in Adams' efforts on economic development, on trade and investments. Portland's economy relies, in part, on maintaining robust economic relationships with Asia.

Siegel's new job at Metro will hew a bit closer to that economic development work. He'll be helping guide the regional agency's Regional Infrastructure Enterprise, an offshoot of Metro's work grappling with the fallout from what could be steep population growth over the next several decades. Metro's estimating a $27 billion shortfall in the kind infrastructure spending required to provide all those new residents adequate job opportunities.

Siegel says he'll be working with the Port of Portland as part of his duties—and enduring a major political lift as he tries to focus government attention on the issue and reach out to the region's big businesses for support.

"I'm going to try to get things done," he said, before joking: "And there's lots of room for massive failure. It's great."

Siegel says he's helping Hales' office find a replacement—presumably someone willing to wear as many hats. Some city hall observers privately criticize Hales for not adding to his staff, if only a little bit—arguing his staffers are spread too thin on too many issues. But Siegel was more than diplomatic when asked about those dynamics and whether the office might struggle to find someone.

"It's a smaller office. That flexibility has been important," he says. "But it's an enviable thing to be close to a mayor in a small office."