The City's contractor has completed the mudflow debris removal work that began on September 30 in Hurricane Gulch. In total, approximately 2,200 tons of debris were removed from an area that includes the Crescent Avenue right-of-way, the Marin Municipal Water District pump station, and private properties above and below Crescent.
With debris removal accomplished, engineers have been able to assess the condition of the section of Crescent Avenue that was impacted by the slide. The surface of the roadway has been significantly damaged. As a result, it will need to remain closed to through traffic until it can be resurfaced in the spring after the rainy season.
Now that the debris field is clear, the City is working with project managers from Harris & Associates to implement winterization and long-term stormwater management measures in the gully. This is because the stormwater infrastructure that was used to manage runoff in the gully was significantly damaged by the mudflow event.
The winterization measures, which should be finalized by the end of November, will help control stormwater runoff and protect the slopes during the coming winter season. Above the gully, stormwater runoff will be temporarily collected in a drainage inlet and diverted from Sausalito Boulevard to an alternate storm drain. In the gully, winterization measures will include stabilization of the slopes by hydroseeding and installing jute netting to promote grass growth and protect against erosion. A complete set of long-term measures will be implemented in the spring after the rainy season.
Any questions about mudflow debris removal, stormwater management, or slope stabilization may be directed to Public Works Director Kevin McGowan at firstname.lastname@example.org or (415) 289-4176.
About the February 14 Mudflow
A mudflow struck Sausalito's Hurricane Gulch neighborhood in the early morning of Thursday, February 14, 2019
The mudflow originated upslope of Sausalito Boulevard on land belonging to the National Park Service
The City Engineer estimates that the slide consisted of between 6,000 and 7,000 cubic yards of earth and debris
The fast-moving earth and debris swept downhill, crossing Sausalito Boulevard and carrying with it the duplex at 406/408
The house at 57 Crescent Avenue was destroyed at the bottom of the slope
There were no fatalities as a result of the mudflow
Total property damage is estimated at $10 million
Crescent Avenue remains closed between 47 Crescent and Main Street due to the large debris pile deposited at the base of the mudslide
Clean up of the debris pile and the slope between Sausalito Boulevard and Crescent Avenue is expected to begin in early September 2019
June 11, 2019:
Approve and Adopt Continuing the Declaration of a Local Emergency Related to
Storm Activity and Landslides and Authorize Extension of Construction Hours for
Debris Removal (agenda and documents)
May 28, 2019: Mudslide Update and Authorization for the City Manager to Execute Amendment No. 1 to the Professional/Consulting Services Agreement with Harris & Associates for Sausalito Emergency Disaster Recovery Advisory Services (video, agenda and documents)
March 12, 2019: Update on the Local Emergency Related to Storm Activity and Mudslides / Renewal of Emergency Declaration (video, agenda and documents)
February 26, 2019: Report on the Local Emergency Related to the Mudslide Occurring on February 14, 2019 (video, agenda and documents)
February 18, 2019: Consideration of a Resolution Declaring the Existence of a Local Emergency Related to Storm Activity and Landslides Occurring in February 2019 (video, agenda and documents)
Bid notice for re-bid of debris removal project with submission deadline of August 19, 2019