The completion of the new four-lane Austin Road interchange at Highway 99 is expected to lead to a rethink of how Manteca grows to the southeast.

The 1,080-acre area straddling Austin Road south of the freeway was annexed to Manteca in 2010.

The zoning adopted could accommodate up to 13,000 jobs and 10,200 based on planning documents.

It also required a new interchange midway between Austin Road and Jack Tone Road.

That interchange carried a price tag in excess of $80 million at the time as it would require shifting Highway 99 to the east.

A lot has happened since 2010.

The Great Recession derailed the Austin Road Business Park plan.

A push to improve the traffic flow and safety at the 120 Bypass/Highway 99 connector called for a new interchange at Austin Road that wasn’t on the radar even 10 years ago.

The interchange — that Manteca contributed $3.2 million to replace with four through lanes instead of two — was recently completed.

The second phase, that Mayor Gary Singh expects now to be at least four years from groundbreaking, will restore the northbound on ramp and the southbound off ramp with loop ramps under the Austin Road overcrossing.

That is in addition to adding a second transition lane from northbound Highway 99 to the westbound 120 Bypass as well as making the Bypass six lanes between Airport Way and Highway 99.

The mayor said the new interchange when the ramps are restored will eliminate the need for a new expensive interchange that Raymus Parkway was originally going to be connected to as development occurred.

Singh points out such an interchange would now have significantly more benefit for Ripon than it would Manteca.

Singh instead believes a rethink should still take Raymus Parkway east across Austin Road.

Instead of tying into an expensive and now unnecessary interchange from Manteca’s perspective, Raymus Parkway should curve to the north and then intersect with the new connecter street with Atherton just beyond the southern base of the new interchange.

The mayor said the loop — saddling Austin Road with ties into Atherton Drive as it heads south and Raymus Parkway that will cross south Manteca and connect with McKinley Avenue — could support more intense commercial than originally envisioned.

It would create an opportunity for higher density housing east of Austin Road — possibly rows of townhomes similar to near downtown Livermore, apartments, and such to help further enhance the potential for commercial.

The mayor also said the business park portion may not to be as large but it could be rethought to maximize the ability to have rail spurs to offer Manteca an advantage over Tracy and Stockton when it comes to landing major distribution centers that rely heavily on rail movements.

To contact Dennis Wyatt, email dwyatt@mantecabulletin.com