Highway 1 at Big Sur set to reopen in September

Highway 1 at Big Sur was first closed in early 2017. The last portion of the scenic route is expected to reopen in September. Highway 1 at Big Sur was first closed in early 2017. The last portion of the scenic route is expected to reopen in September. Photo: Kodiak Greenwood / Special To The Chronicle 2017 Photo: Kodiak Greenwood / Special To The Chronicle 2017 Image 1 of / 8 Caption Close Highway 1 at Big Sur set to reopen in September 1 / 8 Back to Gallery

A seven-mile length of Highway 1 along the southern Big Sur coastline that has been closed for a year, forcing long detours, is expected to reopen in September, Caltrans announced Monday.

The gorgeous stretch of roadway at Mud Creek has been closed since April 2017 — shortly before a tremendous landslide dislodged more than a million tons of rocks and mud onto Highway 1 and into the sea on May 20.

Amazingly, no one was hurt. Perilous conditions had prompted Caltrans to close off access three weeks earlier to visitors, then to locals, and — with a week to spare — even to their own workers. The slide, the largest in known history along the Big Sur coast, enlarged the coastline by 15 acres, Caltrans said.

“It’s like Mother Nature went bananas,” said Caltrans spokeswoman Susana Cruz. “Nobody else could have done that.”

The closure begins to the north of the tiny enclave of Gorda and continues seven miles south to just above Salmon Creek Falls.

Caltrans’ solution for drivers has been to build a quarter-mile stretch of roadway across the landslide, buttressed with stabilizing material, including rocks, netting and berms.

The road closure has forced visitors from the north, hoping to take scenic Highway 1 to reach such favorite sites as the elephant seals at Piedras Blancas and San Simeon, to cut inland.

The new estimate for the new road to be open to traffic is mid- to late September, Caltrans officials said.

Nanette Asimov is a San Francisco Chronicle staff writer. Email: nasimov@sfchronicle.com Twitter: @NanetteAsimov