County planners and others monitoring growth in Crestview, the 18,500-population county seat of Okaloosa County, are coming up with some startling numbers.

If all 8,300 housing units in the city's review pipeline are built, that new construction alone could add more than 21,000 residents. Outside the city limits, the pace of development is even more arresting. Between rezonings, land-use changes and subdivision plans processed last year and through February this year, another 13,996 housing units are being blueprinted for northern Okaloosa, including many around Crestview -- roughly equating to another 34,990 people, says county planning manager Terry Jernigan. Among the projects is a 900-home development by developer D.R. Horton that's being considered for annexation into the city. Annexations could eventually double Crestview's footprint.

To cope, the city plans to double sewage treatment capacity, add two fire stations and draft connector roads away from thoroughfares.

Driving the rush of residents to Crestview are an abundance of land and lower prices. The county's southern half is essentially built out, says Jernigan. The influx reflects metro-area job growth -- 4.2% between 2004 and 2005 -- along with scheduled Eglin Air Force Base expansion and in-migration of sun-seeking retirees.