Counties work on $30 million effort to widen McHenry, replace Stanislaus River bridge

Stanislaus County officials and their counterparts in San Joaquin County keep working on a plan to remove the bottleneck at North McHenry Avenue and River Road, just north of the Stanislaus River bridge, and improve the traffic corridor between Modesto and Escalon.

San Joaquin County replaced the four-way stop with a roundabout two months ago, reducing a 20-minute wait for some motorists to less than a minute.

But the ultimate fix is much more involved and costly – exceeding $30 million. In the fall, contractors could bid on a project to replace the Stanislaus River bridge with a four-lane span. San Joaquin County, the leader for the effort, hopes to begin construction on the two- to three-year bridge replacement in spring 2017.

Tuesday, Stanislaus County supervisors are expected to hire Dokken Engineering of Folsom for environmental work and designs for widening North McHenry to four lanes between Hogue Road and the bridge. The $783,785 engineering contract is a consent item set for routine approval.

Dokken was among four firms that submitted proposals.

In 2009, an engineering firm completed the design for a wider McHenry from Ladd Road to Hogue. San Joaquin officials also have plans for improvements north of River Road on their side of the river.

Dave Leamon, deputy public works director for Stanislaus, said the northern-most portion of McHenry is traveled by 13,000 vehicles a day. Before the roundabout, the stop sign at McHenry and River Road caused peak traffic to back up for a mile south of the intersection.

“You definitely need to start widening a two-lane road at 18,000 (vehicles per day),” Leamon said.

The new bridge over the Stanislaus River is expected to cost $18.5 million, with a federal program providing 89 percent of the funding, Leamon said. San Joaquin and Stanislaus counties each will pay slightly more than $1 million to cover the 11 percent.

The $12 million estimate for widening the 2-mile stretch of McHenry is especially costly because of a slough bridge, officials said. County Public Works is studying what needs to be done with the smaller bridge.

A combination of local and state transportation funds will pay for the additional two lanes and turn lane for McHenry. Officials said the state transportation funds have been delayed until 2020, so they won’t begin the McHenry work until then.

Leamon said traffic will continue using the Stanislaus River bridge during construction of the larger span. The current lanes will remain open as the additional lanes are added on the east side. The new bridge also will have a turn lane for the McHenry-River Road intersection.

The Board of Supervisors will meet at 9 a.m. Tuesday in the basement chamber of Tenth Street Place, at 1010 10th St., in Modesto.

This story was originally published June 27, 2016 at 7:28 PM with the headline "Counties work on $30 million effort to widen McHenry, replace Stanislaus River bridge."