These are diagrams of the traffic switch.

Highway 18 culvert repair update

Caltrans continues operations on a culvert repair project on State Route 18 (SR 18) from 48th Street in San Bernardino to the State Route 138 Crestline bridge.
Crews are ahead of schedule and anticipate conducting two new traffic switches, originally estimated to be in mid-November, beginning the week of Oct. 17.
On Monday, Oct. 17 at 7 a.m., crews will start the prep work by removing the center guardrail and placing K-rail in the area, along with placing signage and indicator markers.
The traffic switch will occur at PM 8 (near 48th Street) and PM 11 (north of Lower Waterman Canyon). Each traffic switch will be a length of approximately 1.5 miles each.
The northbound (upbound) and southbound (downbound) lanes will be brought down to one lane in each direction approaching the traffic switch areas. Traffic in the northbound lane will be pushed onto the other side of the highway, where the guardrail will be removed, so that motorists can drive safely around construction crews and the culvert that is being repaired. Traffic will then be brought back to their original side with all lanes open in both directions.
Motorists are asked to follow all advance warning signs that will be placed to indicate the traffic split and merges. Additionally, they are asked to slow down in the work zone regardless of the crew’s presence.
These traffic switches will be in place for approximately three months and remain overnight.