Barbara Donnellan, Arlington’s witty but earnest county manager, is a tad self-congratulatory when talk turns to her hometown’s inarguable status as the most livable Shangri La in these United States. But she makes her case.

Donnellan spoke Dec. 8 at a banquet with the Arlington Committee of 100, that open-admissions club of county elite that meets monthly at Marymount University.  She declared how “lucky we are to be in Arlington at this time, this place.” She said her “caring community” is the “envy of others in the region” because of low tax rates and its mixed-use transit-oriented vision that “allows us to recover faster” from the recession.

She was just warming up.

A 27-year county veteran who has worked in finance and libraries, Donnellan shared thoughts on her first year in a job to which she was promoted from “acting” status following what felt like a “seven-month job interview.” Her familiarity was reassuring after the board’s unsuccessful attempt to have an outsider succeed Ron “walks on water” Carlee, who now walks the floors of the International City/County Management Association.

Donnellan moved here in the early ’80s, back when county offices used typewriters, the current courthouse was a parking lot and Clarendon nightlife meant Lum’s restaurant and Sears. Her role models then were two local political stars, the late Ellen Bozman and state Sen. Mary Margaret Whipple, who has since scaled the prestigious heights of being a columnist for the Falls Church News-Press.

Donnellan vowed to continue Arlington’s progressive zoning and transport vision laid out in the 1960s and ’80s. She honored the small businesses that died then to make room for 11 Metro stops and the canyons of the Ballston-Rosslyn corridor. “Sometimes you have to have a vision and be brave enough to see it through,” she said.

During Donnellan’s first week on the job, days before Thanksgiving 2009, a water main broke near Walker Chapel. It caused the death by electrocution of a county employee. Knowing the risks of a water shutoff for Arlingtonians preparing to bake pies and receive guests, she was thrilled that Fairfaxians helped by filling cisterns and supplying piping. When staff phoned her on Thanksgiving morning with news that the water was back, she knew she had a great team.

Now Donnellan presides over a huge agenda that includes revitalizing Columbia Pike and reconceiving Crystal City, forging a rare partnership with Fairfax and Alexandria to build light rail. She must preserve the social safety net, having just visited the county’s winter homeless shelter. And she can’t stint on amenities-the new Cherrydale firehouse, the Trader Joe’s bound for Clarendon, the area’s most plentiful bike paths, and the “generational investment” in open-space playing fields in Long Bridge Park.

“Don’t take these things for granted,” she said. The downturn forced the county to cut 160 positions and $33 million from the budget. Revenue growth is now at only 1 percent (last year it was minus 7.2). Employment will be impacted by coming cuts in Pentagon contracting.  The schools must accommodate 1,000 new students, and no one can find $2 million to refurbish the Lubber Run amphitheater.

“Change is necessary for sustainability, she said, and “we will continue to move forward and create new realities to adapt to change.”

The audience was its usual exemplar of politesse, but a few skeptics posed questions. Does Arlington need an inspector general? (“That’s a gotcha thing, and we prefer to do it in-house.”) What about the decline of free parking? (“Our goal is get more people out of their cars.”) What have all the tax hikes and new initiatives gained us? (“There’s no easy answer because it’s incremental,” but you wouldn’t do without technology such as computers in police cars.)

Donnellan said she learned a lesson after vocal citizens shouted down county proposals to close the Gulf Branch Nature Center and the Cherrydale Library.

Asked how she would reach out to the twentysomethings influxing into Clarendon- who’re more into social networking than reading the staid county newspaper-she joked, “I’m considering requiring all my staffers to go to bars every night.”

In running a $1 billion organization of 3,500 employees, Donnellan rightfully calls herself a “steward of the public trust.” She sleeps better now that she’s no longer just “acting,” enjoying confidence in her staff and clear board support. I won’t argue.

Charlie Clark may be e-mailed at cclarkjedd@aol.com