As noted in the Crestwood to Ocotillo section, the abandoned sections of Old Highway 80 through Myer Creek Canyon were devastated by a massive flash flood as Hurricane Kathleen (by that time a tropical storm). Other canyons in the area combined to create a massive wall of water and mud that destroyed the community of Ocotillo. Below is a Youtube video of the effects on the community.
From Ocotillo to El Centro, Old Highway 80 is known as the West Evan Hewes Highway and is signed as County Highway S80, a nod to it’s history. The road continues to run West to East, north of present-day Interstate 8.
At El Centro City Limits, the road begins to be named West Adams Avenue. At the State Highway 86 intersection, Old Highway 80 and State Highway 86 briefly are coterminous and the highway turns ninety degrees to the South to become Fourth Street. At the corner of Fourth Street and Main Street, State Highway 86 continues South while Old Highway 80 (County Highway S80) continues East as East Main Street.
As Old Highway 80 leaves El Centro, the road reverts to East Evan Hewes Highway. The next major stop for Old Highway 80 is the City of Holtville, where it becomes coterminous with State Highway 115. The Highway turns North where at 5th Street, it continues East and moves Southeast back towards Interstate 8. State Highway 115 leaves the route at the Interstate, while Old HIghway 80 runs directly to the North of Interstate 8.
At Gordon’s Well, the highway is split by Interstate 8 and the All-American Canal. I believe the road continued through the Algodones Dunes as Grays Well Road. The pre-Highway 80 Plank Road can be easily located to the South of Grays Well Road as well.
Old Highway 80 picks up again along Araz Road signed as County Highway S24. The road again runs North of Interstate 8 until present-day Highway 8 business joins the road through the town of Winterhaven as Winterhaven Drive. On the West end of Winterhaven, County Highway 24 continues East (in California) as Quechan Road, while Interstate 8 business turns directly South and continues over the freeway and the Colorado River into the State of Arizona and the City of Yuma.