Sunny skies and ceremonial shovels marked the start of a massive 2,300-acre, $2B, 15-year buildout for Arlington's sustainable Viridian mixed-use community in Arlington last week. It's one of the largest urban infill projects in the US.

Here's Huffines Communities prez Robert Kembel, Arlington Mayor Robert Cluck, and co-owners Donald  and Phillip Huffines celebrating the launch of 400k SF of office and medical space and 400k SF of retail, plus single-family homes, condos, and high-end multifamily. The project got financing in mid-April (Equity also from CrossHarbor Capital Partners and debt from Plains Capital Bank, as well as bonds underwritten and sold by First Southwest and Stiefel Nicholas), Robert K tells us. And now, the 12-month process of extensive hydraulics, water infrastructure work, and other site development has begun. The Inaugural Village segment will feature seven builders and homes ranging from $250k to $2M that'll start in May 2012.

Located in North Arlington, the site stretches from SH 360 on the east to Collins Street on the west and from the Trinity River near I-30 northward to 1.5 miles south of Hwy 183. Viridian will include more than 3,600 single-family homes. Calthorpe and Associates? Peter Calthorpe will design and plan it. Other partners include Graham Associates, TBG Partners, Applied Ecological Services, River Legacy Foundation, and Woodley Architects. Last fall, Huffines also started construction on a 90-acre $300M infill multifamily community in Lewisville.