Mark Stettler's Camden roots go deep. As a kid he lived in Cramer Hill, playing at the fire-prone Harrison Avenue Landfill, near the ex-boatyard where his great-grandfather Rickenbach built tugs, barges, and yachts.

Now, he works rebuilding Camden: Stettler is vice president at T&M Associates, consulting engineers to the sprawling, taxpayer-backed Holtec International, Subaru, Camden County, and South Jersey Port Corp. projects transforming the waterfront and downtown of the Philadelphia region's long-depressed second city.

Though in 2007 he ran for county freeholder against the regular Democratic organization, and got creamed, Stettler today has nothing but praise for the political-

corporate-labor-nonprofit coalition that has secured massive state tax breaks as an incentive for suburban companies to move downtown.

"George Norcross has been great for Camden," Stettler says of the insurance broker, Cooper Medical chairman, unpaid Holtec director and political kingmaker who has lined up backers for the downtown and waterfront building boom.

"He has everyone working on the same page," Stettler tells me as we stop not too long ago by the fast-rising Holtec headquarters and power-plant parts factory complex, on the site of the old New York Shipbuilding & Drydock Co., which closed in 1969.

Camden presents special problems for builders. "There's not a job in Camden that doesn't have environmental problems," Stettler says.

There are spilled fuel and chemicals underground, to be excavated or sealed. The light soil is prone to crushing, even under roadbeds, let alone heavy construction. "The ground here is like very tight sponge," says Stettler, compacting over months as weight forces water out.

At the Subaru site near Campbell Soup headquarters, heavy dirt is pre-compacting lighter soil so Brandywine Realty Trust can start work on a five-story, 250,000-square-foot headquarters and 83,000-square-foot training center after testing later this year.

Over its 50-acre site, Holtec has half-completed a seven-story office headquarters facing Philadelphia, more than a mile away across the gray Delaware River, and at least two larger manufacturing structures and such high-end amenities as a helipad.

Initial plans call for 900 staff, many of them moved from the previous Holtec headquarters in Marlton.

It's also Holtec founder Krishna Singh's ambition to build a class of small nuclear-electric plants, which could in time employ several thousand, unlikely as that may seem in this era of cheap natural gas and oil.

Farther west, T&M is also helping with the $20 million rebuild of the Camden County office complex on Mount Ephraim Avenue, across from a site Stettler says is under consideration for an indoor agricultural facility.

Driving through Cramer Hill, Stettler names classmates who died young or scored long prison terms - but also hometown connections Frank Moran, who grew up to be City Council president, and the Sadler clan, whose patriarch, Rodney, chairs the Camden planning board.

Stettler also made useful friends at Rutgers, where he started a Pi Kappa Sigma fraternity chapter before transferring to get his engineering degree at night from Drexel.

There are sporadic traffic jams in downtown Camden now, outside the shining charter schools and the growing Cooper Medical complex. Parking on the surface lots is big business. Stettler looks up at the PATCO train crossing the Ben Franklin Bridge and laments the lack of a waterfront station: Why should people have to drive to this urban-renewal site, where Liberty Property Trust plans a billion-dollar, state-backed office campus designed to lure South Jersey's remaining corporate headquarters?

I asked Mayor Dana Redd earlier this summer whether she's worried that the building will force her constituents out of town. Forced displacement "is a real issue," she said, but she's more concerned about the continued voluntary exodus of Camden residents once they get good jobs. "We want to make sure we have the quality of housing here that can retain our residents in the city, our millennials."

I ask Stettler why so much public money is going into rebuilding a place that businesses and middle-income residents chose to leave.

In South Jersey - in all of suburban America, where half the people now live - "we've built more than we can sustain," Stettler tells me.

Without continued new development to help pay for maintenance, spread-out township roads, sewers and utilites wear out: They cost too much to maintain without constant tax increases. Densely populated cities are more efficient to maintain - if you don't defer maintenance for years, forcing costly catch-ups.

Suburban traffic (Stettler lives in neighboring Audubon) and rising suburban property taxes "are lighter fluid for our barbecue" in Camden, he says.

And the waterfront cranes, the charter schools, the Cooper complex, "this is our Kickstarter. We have reached critical mass. Enough projects are now underway. The next step is where we see private money coming in," without matching government-backed loans, grants, and tax breaks, he says hopefully.

But where, I ask, is that happening here? Camden's big developments are still like solar or wind power: They require a public subsidy.

"We've got some good stuff going," Stettler insists. "We are fortunate to be adjacent to Philadelphia, which has a lot going on." He looks happily across the gray Delaware to the big city, with its apartment and hospital boom and its population 20 times Camden's. "There's nothing wrong with a little Philly-Camden synergy."