Images

The USGS landslide team monitors and continues to update the hazard map models based on data collected in burn areas. This information improves future models and provides better hazard assessments used by officials for emergency response and decision making. Many of the steep hillsides burned and denuded in California fires repel water rather than soak it in.

The atmospheric river, a narrow, powerful track of water vapor that can deliver tremendous volumes of rain, hit the central California coast and stalled there between January 26 and 28, 2021 — with catastrophic consequences.

The storm that hit California’s coast between Jan. 26 and 28, 2021, blew out a portion of Hwy 1 near Big Sur. On Saturday, a USGS reconnaissance flight snapped this dramatic photo above the Rat Creek drainage showing the debris flow.

The atmospheric river, a narrow, powerful track of water vapor that can deliver tremendous volumes of rain, hit the central California coast and stalled there between January 26 and 28, 2021 — with catastrophic consequences.

The atmospheric river, a narrow, powerful track of water vapor that can deliver tremendous volumes of rain, hit the central California coast and stalled there between January 26 and 28, 2021 — with catastrophic consequences.

On May 20, 2017, this section of the Big Sur coastline experienced a huge landslide that wiped out scenic coastal Highway 1. By July 2018 the roadway was reopened.

California's Highway 1 snakes its way along the steep terrain of the Big Sur coast. The bridge over Villa Creek can be seen in the left of the photo, as well as a retaining wall built under the freeway towards the center. These are just a few of the engineering feats by Caltrans to keep the roadway intact.

A section of Highway 1 along the California coast in Big Sur with more examples of the numerous debris flows and mudslides that occur following a heavy rain. This section is just south of the Rat Creek debris flow that completely washed out a large chunk of the highway.

A two-day rainstorm from January 26-28, 2021 caused numerous mudslides, debris flows, and other issues along California's coastal Highway 1 through Big Sur. This section is just north of Kirk Creek, at a drainage where mud was washed across the roadway. Plumes of the muddy runoff are clearly visible in the ocean.

A two-day rainstorm from January 26-28, 2021 caused numerous mudslides, debris flows, and other issues along California's coastal Highway 1 through Big Sur. This section is just north of Kirk Creek, at a drainage where mud was washed across the roadway. Plumes of the muddy runoff are clearly visible in the ocean.

A two-day rainstorm from January 26-28, 2021 caused numerous mudslides, debris flows, and other issues along California's coastal Highway 1 through Big Sur. This section is just north of Wild Cattle Creek. Mud washed across the roadway from the cliffs in numerous locations along the 70+-mile stretch of this scenic coastal road.

USGS photographs taken from a contracted small airplane are used to build three-dimensional representations of the hillslopes of Big Sur, California, as shown here for the Mud Creek landslide site in 2017.  Blue symbols show the locations of individual photos obtained on the flight, and the gray area shows the hillslope landscape created from the photos using S

Computer images showing the coastal cliff area of Mud Creek on the Big Sur coastline, central California, where on May 20, 2017 a catastrophic landslide destroyed over 400 meters of scenic California State Highway 1. These illustrations show the changes to the digital surface models of Mud Creek during the three primary phases of the landslide: (

Shaded-relief map of central California showing location of the Big Sur area (white dashed line). Red line shows the San Gregorio-Hosgri fault (SGHF) and the Big Sur Bend between Point Sur (PS) and Piedras Blancas (PB). Black lines show other faults.

Perspective view of part of the Big Sur Bend in the San Gregorio-Hosgri fault. The steep slope beside the fault results from uplift along the fault, which is part of the strike-slip fault system that forms the boundary in California between the Pacific and North American tectonic plates.

USGS scientists produced an animated GIF in coordination with the California Department of Transportation (Caltrans) re-opening of State Highway 1 through Big Sur on July 18, 2018. In 2017, the massive Mud Creek landslide buried a quarter-mile of the famous coastal route with rocks and dirt more than 65 feet deep.

Close-up views of the toe of the Mud Creek landslide created from air photos taken May 27 (top), June 13 (middle), and June 26 (bottom). Caltrans built roads on top of the slide for assessment and monitoring activities.

Big Sur coast. Red squares mark some of the sites damaged by 2016–17 winter storms, including Mud Creek and Paul’s Slide areas.

Mud Creek slide from south side of north upper terrace (above north and south berms). Note tension cracks and offset on the terrace to the north.

A series of images from various sources of shaded-relief topography show the progression of the Mud Creek landslide area, from 2010 through October 12, 2017.

Sources:

In 2017, the massive Mud Creek landslide buried a quarter-mile of the famous coastal route, California’s Highway 1, with rocks and dirt more than 65 feet deep. USGS monitors erosion along the landslide-prone cliffs of Big Sur, collecting aerial photos frequently throughout the year.