Manteca is pushing for the reopening of the southbound offramp on Highway 99 at the Austin Road interchange by year’s end.

That’s when the work on the replacement Austin Road overcrossing is expected to be completed.

As things stand now, southbound traffic may not be able to exit at Austin Road for at least three more years. That assumes a best case scenario of full funding being nailed down for the second phase of the Highway 99/120 Connector Project in the near future.

Mayor Gary Singh believes the reopening as part of the initial phase is do-able.

That’s because when the work on the first phase is done, there will be four lanes, and not three, passing south under the replacement overcrossing.

The fourth lane is the second transition lane being added from the eastbound 120 Bypass to southbound Highway 99. That lane will eventually end once it clears the overcrossing with freeway traffic being forced to merge to the left.

The original plan called for the off-ramp to remain closed until the third phase of the Highway 99/120 Connector Project was completed.

That phase included elaborate — and expensive — braided ramps with bridge structures.

Union Pacific Railroad denial of a request to place a column support for a bridge structure in its right-of-way along Moffat Boulevard prompted the San Joaquin Council of Governments to rethink the next two phases.

That led to a new strategy to restore the southbound exit to Austin Road by taking it under the overcrossing and then having it curve back to northbound Moffat similar to the southbound ramp at the Pelandale exit on Highway 99 in Modesto.

Doing so would require the removal of the propane business.

The original three-phase approach with a braided off-ramp to Austin Road would have started between Main Street at the Moffat overcrossing on the 120 Bypass tying into a ramp to reach Austin for southbound traffic wanting to exit that would have started north of the 120 Bypass/99 interchange.

It was for what Caltrans called optimum traffic flow by minimizing the impact of traffic trying to reach the exit and transition traffic in the new outside lane from the 120 Bypass having to merge as it headed south on Highway 99.

The close proximity of the 120 Bypass and Austin Road interchanges on Highway 99 led to the original design.

Had the three-phase approach not been dropped in favor of the new two-phase approach, the earliest the ramp could be reopened was pinned at a minimum of 10 years out.

Meanwhile, funding has become more of a struggle to secure making the three phase approach with braided ramps difficult to pursue.

The working solution now is to restore the southbound ramp in a second and final phase when the second transition lane from northbound Highway 99 to the westbound Bypass is built.

In that scenario, the City of Manteca would still have to come up with funding for the new replacement ramp. It would be substantially less than the braided ramp approach.

The city is expected to devise an area of benefit fee to place on future southeast Manteca growth to cover the cost.

Future of the northbound

ramp from Austin Road

While most of the city’s attention and local commuter anguish has been focused on restoring the southbound ramp, keeping the northbound on-ramp in place may be a different issue.

The short merge with Highway 99 before 120 Bypass westbound effort contributes to the slowdown that leads to stop and go traffic during the morning commute and at various times of the day and weekends.

Commuters returning from the Bay Area in southeast Manteca where the city has over 1,500 acres yet to be developed, tend to use the southbound exit at Austin Road to avoid surface traffic on South Main with a lower number using the on-ramp in the morning.

That said, work is now underway on the 797 home Yosemite Greens neighborhood along Austin Road just to the northeast of the Austin/99 interchange.

If current trends hold, the vast majority of the future residents will head west out of Manteca to reach jobs in the Bay Area, Tracy, and Lathrop.

The city is not seeking to reopen the northbound on ramp at this time.

Instead, it will be restored in the second phase by creating a loop similar to the one for the northbound on ramp at Lathrop Road and Highway 99.

The loop will take the replacement ramp under the new overpass to allow for a longer lane merge before the transition lanes to the west 120 Bypass.

To contact Dennis Wyatt, email dwyatt@mantecabulletin.com