Marin County experienced a second day of disruptive flooding on Saturday as exceptionally high king tides coincided with a winter storm surge and heavy rain, inundating roads and local businesses for hours. Floodwater rose rapidly at the Marin RV Park in Larkspur, cutting off the driveway in under 15 minutes and prompting hurried evacuations. Around 11 a.m., floodwaters overtook both directions of Highway 101, stranding multiple vehicles and prompting forced traffic restrictions. Emergency crews and business owners mounted a fast response as residents moved cars and sandbagging efforts began at affected sites.
Key takeaways
- Marin County faced a second consecutive day of flooding driven by the highest king tides recorded since 1998 combined with heavy rainfall and a storm surge.
- At the Marin RV Park in Larkspur, water cut off the driveway in less than 15 minutes, prompting residents like Roy Demicco to move family and vehicles to safety.
- Highway 101 was overtopped near central Marin at about 11 a.m.; California Highway Patrol initially held traffic and later allowed a single lane through, leaving several cars stranded.
- Reported local water depth reached approximately four feet in places within residential driveways; managers relocated some RVs to higher ground.
- Businesses including a car wash and a gas station at Shineology reported flooded garages and potentially damaged pumps; nearby Trader Joe’s was temporarily cut off by floodwater.
- Central Marin Fire Department answered numerous calls and emphasized the public safety message: “Turn around. Don’t drown.”
- A video circulated showing a car floating near the Lucky Drive exit; the driver was reportedly wet but uninjured and declined comment.
Background
Coastal communities around the Bay Area periodically face flooding when seasonal king tides align with strong Pacific storms. King tides are predictable, astronomically driven high tides that become hazardous when amplified by storm surge and heavy precipitation. Marin County’s shoreline and low-lying corridors, including parts of Highway 101, are particularly vulnerable because of limited elevation and constrained drainage. Local officials, emergency services and businesses have increased preparedness in recent years as sea-level rise has lengthened the season when high tides produce disruptive flooding.
Prior incidents have shown how quickly tidal flooding can cascade into transportation and business interruptions: a blocked driveway at an RV park can strand residents and their vehicles, while inundated arterial roadways force traffic closures and emergency responses. Property managers and municipal crews often rely on sandbagging, temporary barriers and rapid vehicle relocation to limit damage during short-duration, high-water events. The combination of the highest recorded king tides since 1998 with a strong storm surge presented a rare convergence that tested those short-term defenses on Saturday.
Main event
Floodwater rose rapidly at the Marin RV Park in Larkspur, where residents reported the access road became impassable in under 15 minutes. Roy Demicco described the scene as chaotic as he moved to protect his family and possessions while watching water encroach on parked vehicles. Managers at the park, including Sed Conklin, said some RVs were moved to higher ground and that driveway depth reached approximately four feet in places.
By about 11 a.m., floodwaters covered both directions of Highway 101 in central Marin, forcing the California Highway Patrol to suspend traffic briefly before reopening a single lane. Several drivers were stranded; one motorist in a Mini Cooper reported the car lost power while trying to traverse the deeper section and remained stuck until assistance arrived. A separate video circulated showing a vehicle floating near the Lucky Drive exit; the occupant exited wet but reported to be okay and declined on-camera comment.
Local businesses felt immediate impacts. Workers sandbagged the Shineology car wash after floodwater entered the detailing garage and managers warned gas pumps may be damaged. Staff at a nearby Trader Joe’s watched the water cut off access to the store, temporarily isolating employees and customers. Emergency responders from the Central Marin Fire Department handled a high volume of calls and reiterated standard flood-safety guidance to residents and motorists.
Analysis & implications
The incident underscores how even short-duration tide-driven flooding can disrupt transportation networks and local commerce. Highway 101 is a major regional artery; when it is overtopped, detours and delays cascade across surrounding streets, burdening emergency response times and local businesses. As maritime and meteorological patterns shift, these episodic but intense events may become more frequent, increasing maintenance and resiliency costs for local governments and private operators.
For property owners in low-lying coastal zones, the event highlights the limits of reactive measures like sandbags and vehicle relocation. While such tactics reduce immediate losses, repeated exposure increases the likelihood of cumulative damage to structures, vehicle fleets and underground utilities. Businesses that rely on street-level access — grocery stores, gas stations, auto services — are particularly exposed to revenue disruption when water isolates storefronts for hours.
Policy and planning implications include accelerated investments in permanent flood defenses, revised road-elevation projects, and updated emergency-routing protocols. Planners must weigh the costs of infrastructure upgrades against the increasing frequency of compound events: the concurrence of king tides, storm surge and heavy rain. Short-term measures should be paired with longer-term strategies, including improved drainage, protective berms, and zoning adjustments in the most vulnerable corridors.
Comparison & data
| Location | Time/Day | Notable detail |
|---|---|---|
| Marin RV Park, Larkspur | Saturday morning | Driveway cut off in <15 minutes; ~4 ft depth reported |
| Highway 101 (central Marin) | About 11:00 a.m. | Both directions flooded; traffic held then reduced to one lane |
| Shineology car wash | Saturday afternoon | Detailing garage flooded; pumps likely damaged |
The table summarizes verified on-scene details reported during Saturday’s flooding. These measurements and times come from live reporting and statements by residents and emergency personnel; they indicate rapid onset and short-duration inundation events that nonetheless produced significant local disruption. Historical context — king tides highest since 1998 — frames this as an unusually severe tidal event compounded by storm conditions rather than a routine tidal occurrence.
Reactions & quotes
Local residents, business managers and emergency officials voiced alarm and emphasized safety. Their remarks illustrate how personal impacts and institutional responses intersect during sudden flood events.
“So, it’s been a mess today,”
Roy Demicco, Marin RV Park resident
Demicco described fast-rising water and the urgent need to move family members and vehicles. Staff at the park corroborated that some units were relocated to higher ground in anticipation of further rising water.
“Turn around. Don’t drown. If you need help, call 911,”
Brian Peterson, Central Marin Fire Battalion Chief
Battalion Chief Peterson summarized the fire department’s central message, noting crews handled multiple calls and urged motorists to avoid driving through standing water. The department also coordinated with CHP on traffic control along Highway 101.
“We weren’t expecting this much water. Everybody is scared,”
Jose Son, Shineology manager
Managers at the car wash reported floodwater in the detailing bay and possible pump damage, prompting immediate sandbagging and cleanup efforts while awaiting damage assessments.
Unconfirmed
- Precise extent of structural or long-term damage to the Shineology gas pumps remains unverified pending formal inspection.
- Total number of vehicles irreparably damaged on Highway 101 and at the RV park has not been finalized by authorities.
- Any broader utility or underground infrastructure damage tied directly to this single event has not been publicly confirmed.
Bottom line
Saturday’s flooding in Marin County was driven by a rare convergence of the highest recorded king tides since 1998, an active storm surge and heavy rain, producing rapid inundation that cut off driveways, stranded vehicles and disrupted businesses. Short-term responses — sandbagging, vehicle relocation and traffic management — limited immediate harm but will not prevent repeated exposure if similar compound events become more common.
For residents and planners, the incident reinforces the need to review evacuation procedures, update flood-response protocols, and accelerate investments in infrastructure resilience. In the coming days local authorities and business owners will need to assess damage, restore services, and consider whether additional protective measures are warranted ahead of future king-tide cycles.
Sources
- ABC7 San Francisco — Local news (live coverage and reporting)