Napa County Sees 14 Inches Of Rain; Flood Concerns Not Over

NAPA VALLEY, CA—Yountville had the second-highest rainfall total from the most recent atmospheric river to hit the Bay Area, the National Weather Service reported Wednesday.

From Friday through Tuesday, the Napa Valley town received 14 inches of rain. Mount Tam, where nearly 18 inches of rain fell, had the highest rainfall total in the region, preliminary figures showed.

The rain led to flooding issues throughout the county and the North Bay. Tuesday night, the Napa River crested at 18.39 feet in St. Helena, reaching the "minor" flood stage. In Yountville, the Napa River rose to 24.27 feet — just below minor flood stage.

Napa River Flood Scenarios From The National Weather Service

• 32 feet: Disastrous flooding. Widespread flooding occurs in the entire Napa Valley, with transportation impossible. Disastrous damage to homes and businesses in the Napa Valley, especially in the city of Napa.
• 30 feet: In the city of Napa, flooding in the south oxbow area expands south towards Tulocay Creek and Imola Avenue begins to flood on both sides of the river. Major flooding continues in the Napa Valley, with major damage to homes and businesses, especially in Napa. Transportation impossible in Napa Valley. 20,000 acres possibly flooded in the Napa Valley. Between 5,000 and 7,000 evacuations occurred in the Feb. 18, 1986 record flood, 37,000 cfs, 30.20 feet.
• 29 feet: In the city of Napa, the Soscol corridor between the bypass and Lakepark is inundated, and the Lakepark area begins to flood and flow begins to leave the Napa River at Riverside Drive.
• 28 feet: Major flooding. In the city of Napa, significant flooding occurs near Lincoln Avenue with some secondary roads inundated. Major flooding of towns within the reach of the gage, especially in Napa. Inundation of agricultural land and major damage from bank erosion and sediment deposition in Napa Valley. Transportation becomes difficult throughout the Napa Valley. The Jan. 1, 1997 flood measured 28.07 feet and cut off east-west travel except at Highway 29 over the Napa River.
• 27 feet: In the city of Napa, moderate flooding begins on the east side of Napa River near Milliken Creek Inn.
• 26.0 feet: Moderate flooding. In the city of Napa, flow begins to leave the Napa River channel in the South Coombs area (north of Imola Avenue) and the south oxbow (near Taylor Street). Crop losses and erosion damage become serious. Moderate flood damage in lower parts of urban areas along the reach. Transportation in Napa Valley becoming difficult. The flood of Feb. 3, 1998, measured 26.72 feet.
• 25.0 feet: Flood Stage. Flooding of the lowest parts of towns in reach begins. Inundation of lowest agricultural land in Napa Valley. Some secondary roads are inundated. Moderate damage from bank erosion and sediment deposition throughout the reach.
• 24.0 feet: In the city of Napa, flow begins to leave the Napa River channel at Riverpointe (north of Lincoln Avenue).
• 22.0 feet: Monitor Stage. In the city of Napa, the Napa River Dry Bypass is fully inundated and flow begins to cross McKinstry Street.
• 20.0 feet: Erosion of the lowest agricultural areas along the Napa River begins.

More Rain, More Flood Concerns

Due to flooding from this week's heavy rainfall, Caltrans implemented one-way traffic control on state Highway 29 in Mt. Saint Helena from Robert Louis Stevenson Park north to the Lake County line.

In Sonoma County, a mudslide caused a home to slide into the Russian River in Forestville and led to mandatory evacuation orders for residents along the river from Guerneville to Jenner.

Although Wednesday brought a slight break in the rain, a 90 percent chance of rain is forecast for Thursday in the North Bay and Napa Valley. This brings the possibility that river levels could peak higher than originally forecast, the city of Napa warned.

Moderate rainfall —mainly on Thursday —was likely to result in minor roadway ponding and slow the recession of ongoing river flooding, National Weather Service forecasters said.

The Napa County Office of Emergency Services encouraged community members to keep driving to a minimum.

"Due to the atmospheric river several county roads are currently flooded, or in danger of flooding," Napa County OES said. "Please use caution when navigating roads as not all flooded areas have yet been identified. You are encouraged to keep driving to a minimum until the rains subside. Remember turn around, don’t drown and never drive through a flooded road or area."

The city of Napa cautioned that water from the Napa River could flow over the banks in some general low-lying areas, such as:

• Lake Park and Shoreline Drive area
• Lincoln Avenue from Silverado Trail to the railroad tracks
• Areas just south of Central Avenue to Vallejo, east of Soscol Avenue
• Imola and South Coombs and in marsh areas around the river near Napa Valley College
• Downtown block to First Street bridge and in the vicinity of the Oxbow

"If you are in an area with flood potential, consider moving vehicles to higher ground," city officials said.

Personnel with the City of Napa Fire, Police, Public Works and Parks departments continue to monitor conditions and respond to any issues that occur, the city said.

The city's Corp Yard at 770 Jackson St. is stocked with sandbags for community members who need them.