Historic flooding hits Marin’s low-lying areas

Historically high king tides magnified by a winter storm surge inundated Marin’s low-lying coastal areas on Saturday.

As the tide crested before noon, main arteries like Highway 101 near Lucky Drive were entirely submerged and remained paralyzed for hours. To the north, eastbound Highway 37 was completely flooded and closed. By 2:30 PM, receding waters on 101 near Lucky Drive allowed a single lane of cars to pass in both directions.

Nearby businesses and residential areas in Corte Madera and Larkspur also flooded Saturday, in some instances for the second day in a row. Businesses along the Seminary Drive frontage road near Mill Valley flooded. County officials reported nearby highway exits and on-off ramps were impeded.

Flood-prone lowlands such as northern Sausalito’s Gate 5 neighborhood, the nearby Manzanita park and ride lot under Highway 101, multi-use path into Tam Junction and Mill Valley, and portions of Mill Valley’s Miller Avenue and Camino Alto were also flooded and closed by police.

An estimated 1,500 homes in parts of Tiburon and Marin City lost electricity for several hours, according to public officials.

Low-lying areas of west Marin saw localized flooding in Inverness and Stinson Beach, public safety officials reported.

“We are seeing a significant amount of flooding throughout the county,” said Laine Hendricks, county spokeswoman. “We’re seeing a lot of flooding in the Canal neighborhood (of San Rafael), on North San Pedro Road (in Santa Venetia). But also on the opposite side, as you’re going to Peacock Gap, to China Camp.”

By 4 p.m. a more complete picture of the flooding emerged, based on interviews with public safety and elected officials.

Belvedere Mayor Sally Wilkinson said Beach Road, the paved-over levee connecting that island to downtown Tiburon, was nearly breached by bay waters that were inches from the road’s surface. The inbound lanes of Tiburon Boulevard were “completely covered in water,” she said.

Tiburon was hit with flooding for a second day in a row. “Main Street was closed yesterday and our businesses and restaurants experienced a power outage due to the PG&E equipment flooding due to the king tides,” said Councilmember Holli Thier, a former mayor.

In San Rafael’s Santa Venetia neighborhood, the levee near Vendola Drive was “damaged by flood waters,” Hendricks said. “(The) breech is not catastrophic, but did have a high rate of seepage. Public works assisting with response and immediate repair.”

In Marin City, the pumping system kept water from inundating its low-lying areas, said Sarah Canson, a community services district board member.

“It’s flooding on the other side (of 101),” she said. “That’s the only backup into Marin City; that’s stopping us from making the turn to the highway.”

Canson praised the county’s emergency alert system, Nixle, for texting people about the power outage. “Everybody heard it, which was really nice.”

In central Marin, police also sent out repeated Nixle alerts about road closures around Highway 101, Lucky Drive, Doherty Drive and Fifer Avenue.

Larkspur Mayor Stephanie Andre said flooding extended from east of the highway, where a Trader Joes and mobile home park are located, to west of the highway and the back parking lot at Redwood High School.

“Our public works people are making sure that the pumps are all working,” she said. “The issue is simple — there is too much water.”

Sausalito Mayor Steven Woodside said he saw bay waters reaching Bridgeway, the main thoroughfare, in the city’s north end. Sausalito’s southern waterfront was lucky that winds did not create waves that could have pushed water inland, he said. “When there is true wave action, the bigger waves come across.”

Brayben Murdoch, a National Weather Service meteorologist, said historically high king tides more than seven feet above sea level on Friday and Saturday and a storm surge from the most recent atmospheric river caused the flooding.

“The high tide comes in, it overflows certain areas,” he said. “A lot of times there’s what we call ridge lines where it gets over a certain point, and then when the low tides comes through, the water doesn’t have an opportunity to go back to the bay.”

“Tomorrow (Sunday) looks to be much less, as we hit a high tide of 6.92 feet at the San Francisco gauge,” Murdoch said. “As we head into the next high tide after that, going into Monday afternoon, that one doesn’t look to be in flooding (zone) criteria.”

Most of the rain in coming days will be in the Santa Cruz mountains, he said. But pockets of floodwaters will remain for several days or longer.

“It’s going to be a struggle for certain areas that are pretty much inundated already to get rid of that over time,” he said. “As far as rainfall goes, we’re starting to see a bit of a lull.”

“Most likely, we’ll have to anticipate closing some roads tomorrow (Sunday),” said Mill Valley Police Sgt. David Kollerer. “It just depends on how everything shakes out, especially with the ground being saturated and the rain.”