32' - 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' - 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 the Napa Valley. 20,000 acres possibly flooded in the Napa Valley. Between 5,000 and 7,000 evacuations occurred in the 2/18/86 record flood, 37,000 cfs, 30.20 feet.
29' - In the City of Napa, the Soscol corridor between the bypass and Lakepark in inundated, and the Lakepark area begins to flood and flow begins to leave the Napa River at Riverside Drive.
28' - 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 difficult throughout the Napa Valley. The 1/1/1997 flood measured 28.07 feet and cut off east-west travel except at Highway 29 over the Napa River.
27' - In the City of Napa, moderate flooding begins on the east side of Napa River near Milliken Creek Inn.
26' - 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 the Napa Valley becoming difficult. The flood of 2/3/1998 measured 26.72 feet.
25' - Flood Stage. Flooding of 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' - In the City of Napa, flow begins to leave the Napa River channel at Riverpointe (north of Lincoln Avenue).
22' - Monitor Stage. In the City of Napa, the Napa River Dry Bypass is fully inundated and flow begins to cross McKinstry Street.
20' - Erosion of lowest agricultural areas along river begins.