Manteca will have a rare commodity when the end of 2014 rolls around - a freeway interchange with a major roadway in an urban San Joaquin County setting that isn’t hemmed in by development.

The $250 million widening of the 13.1-mile stretch of Highway 99 between Arch Road and the 120 Bypass includes a new Lathrop Road interchange complete with four travel lanes. Work is expected to start within the year on the interchange that also involves tearing out the Main Street flyover.

Part of that project realigns the West Frontage Road through Delta College’s 160 acres just northwest of the interchange and aligns it with Crestwood Avenue.

Delta College several years ago quietly proposed to Manteca city officials the possibility of developing 350,000 square feet of retail on the land. It is the interchange project and the potential for substantial traffic that has now sparked interest from a developer who wants to buy the land that once was promised to Manteca-Lathrop voters to be developed as a satellite campus. Delta trustees, though, opted to go instead with the Mountain House campus. The only educational use on the site is the Delta College school farm accessed via New Brunswick Road.

Not only would the Highway 99 project build a road through part of the Delta College property but it also will align that road with an extension of North Main Street as four lanes from Northgate Drive to tie into the Lathrop Road intersection and the southbound on and off ramps.

The 160 acres would have high visibility to more than 80,000 vehicles that pass the Lathrop Road interchange on Highway 99 daily. It is also a mile north of Manteca’s busiest intersection - Main Street at Louise Avenue - where the last traffic count had 37,400 vehicles a day passing through it.

“The interchange has the potential to make that area the next big area for retail in Manteca,” Manteca economic development specialist Don Smail told the City Council last week.

The interchange itself is designed to be a calling card of sorts for Manteca. The overpass will be brick-veneered complete with Tidewater-style street lights and landscaping.

Lathrop Road provides direct access to the 1,406-home Del Webb at Woodbridge age-restricted community that is nearly halfway mark for completion. It also connects at mile intervals with Manteca’s other two major north-south streets - Union Road and Airport Way. In addition Lathrop is moving forward with plans to build a second overcrossing of the train tracks. That means traffic will be able to move from Interstate 5 to Highway 99 without having to worry about trains blocking crossing.

It also means Lathrop consumers could also pass the 160-acre Delta College site.

And since Lathrop Road eventually connects with Cottage Avenue, it would effectively have the ability to draw consumer traffic from Manteca east of Highway 99.

The interchange is also expected to make the Rossi property that has been proposed for medical and retail between Highway 99 and the T-intersection of Northgate Drive/Main Street more attractive for development.

There is also undeveloped property between Crestwood and Highway 99 that flanks both sides of Lathrop Road. That is in addition to the northeast quadrant that is also undeveloped but is just outside eth city limits.