Montecito Debris Flows

A Beach Nourishment Opportunity

Beach Erosion Authority for Clean Oceans and Nourishment

Sequence of Events

  • Thomas Fire – December 2017
  • Montecito Debris Flows – january 9, 2018
    • Perhaps 500,000 cy made it to the beach
    • About 70,000 cy deposited on public streets & flood control channels
    • About 400,000 cy deposited in local debris basins
    • Perhaps 1,000,000 cy deposited on private property
  • Aftermath
    • Street & f/c channel sediment taken to Goleta & Carpinteria Beaches
    • Debris basin sediment taken to Buellton & Santa Paula landfills
    • Private property sediment remains in place

What Does Debris Flow Look Like?

Montecito Debris Flows Stats

  • 25 people killed
  • Over 100 homes destroyed & more than 300 damaged
  • Widespread damage to property & infrastructure
  • About 2M cy of sediment released from foothills
  • Sediment mostly composed of sand (80%) along with rocks, logs, etc.
  • Sediment largely uncontaminated

Impact to Beaches

  • Sediment sorted rapidly by waves with finer material moving offshore & coarser material onshore
  • Rocks & boulders deposited at creek mouths – logs & other floating debris scattered along coast
  • Nearby beaches grew wider – new sand blended in well with existing
  • Trucked sediment at Carpinteria & Goleta Beaches had similar effects
  • Water quality impacts significant but short-term

Fernald Point – April 2017

Fernald - April 2017

Fernald Point – January 2018

Fernald Point - January 2018

Fernald Point – February 2018

Fernald - February 2018

Loon Point – April 2017

Loon Point - April 2017

Loon Point – January 2018

Loon Point - January 2018

Loon Point – March 2018

Loon Point - March 2018

Carpinteria Beach – April 2017

Carptinteria Beach - April 2017

Carpinteria Beach – January 2018

Carpinteria Beach - January 2018

Carpinteria Beach – March 2018

Carpinteria Beach - March 2018

Carpinteria Beach - March 2018-b

Carpinteria Beach - March 2018-cCarpinteria Beach - March 2018-d

Goleta Beach – June 2017

Goleta Beach - June 2017

Goleta Beach – January 2018

Goleta Beach - Janaury 2018

Goleta Beach – February 2018

Goleta Beach - February 2018

Goleta Beach – March 2018

Goleta Beach - March 2018

Predicted Shoreline Response

Predicted Shoreline Response

Unique Opportunity for Beach Nourishment

  • Large volume of sediment available on private property
  • Significant benefit if sediment taken to beaches
  • Sediment must be sorted & stored for placement in Winter/Spring
  • Comprehensive SCCBEP-type program needed to:
    • Establish sorting/storage areas
    • Identify beach receiver sites
    • Establish testing, placement & monitoring protocols
    • Secure environmental permits
    • Identify/develop funding mechanism

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