Tom Butt
  E-Mail Forum – 2023  
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  Update on Seacliff Slide
January 6, 2023

City of Richmond Fire and Police were able to reassess homes in the incident area to confirm vacancy.  No homes are occupied, and currently there is no need to evacuate additional homes.  The Police Department is staffing the roadblocks to prevent anyone from accessing the homes or target area.  The road closures are:

  • Seacliff Drive between Seacliff Way and Canal Blvd
  • Seaview Drive from Seacliff Drive to Admiralty Way
  • Seacliff Way from Seacliff Drive to Admiralty Way

Site access is limited to necessary Richmond personnel and public utilities including Veolia, Pacific Gas and Electric (PG&E), and East Bay Municipal Utility District (EBMUD).  We are monitoring the site for earth movement and debris flow. 

On January 4, Veolia and EBMUD checked their utilities in the area.  EBMUD and Veolia reported no leaks in the water system or cracks in the sanitary sewer pipelines respectively.  As a precaution, EBMUD shut off two fire hydrants in the area.  The Fire Department will add an extra fire engine to support the incident

On January 3 and 4, the City’s on-call consultant CSW|ST2, and Cal Engineering & Geology, Inc. (CE&G), subconsultant of NCE, the City’s on-call consultant, reviewed the site.  On the morning of the January 4, a geologist from CE&G confirmed there are two slides present in the hillside east of Sea View Drive.  One of the slides is older potentially occurring several years ago.  The current slide commences near the top of the ridge with its toe likely at the base of the hill along Sea View Drive.  The large cracks at the top of the hill illustrate the landscape scarp.  Cracks in the curbs along Sea View Drive illustrate the presence of the slide at the bottom of the hillside. The geologist will investigate to determine if the slide continues below the homes, which are currently evacuated, including 300 to 314 Sea View Drives. It is anticipated that NCE/CE&G will provide a report with more information late by Friday, January 6.

Early Wednesday morning, January 4, the City retained WR Forde to support the effort.  WR Forde crews completed a video inspection of the storm drain pipe that collects runoff from the concrete ditches located along the hillside.  The investigation found that the pipe is conveying some, but not all, stormwater.  Stormwater is traveling through voids in the trench backfill surrounding the pipe.  Because the grade is steep, the water could be running down the hill in this void space.  This is concerning as this water enters into the subsurface soils of the hillside, which could exasperate instability of the slope.

In the early afternoon of January 4, WR Forde crews attempted to install plastic sheeting to cover cracks in the earth near the top of the hill as recommended by the geologist of CE&G.  Unfortunately, the winds were very strong and destroyed the sheeting.  The contractor brought heavier material, but the winds had increased, and it became unsafe to install.  By 4 PM, the contractor had mobilized plastic sheeting, ropes, sandbags, and stakes near the landslide area with the plan of installing the material on the morning of the January 5 when weather forecasts predicted the winds would lessen.

In the evening of January 4, representatives from the Sea Cliff homeowners association (association) notified the City that they would take over the mitigation effort using the materials brought to the site.  The association agreed to reimburse the City for the material. I will continue to provide updates as this situation evolves.