Flood Watch Through Late Tonight, Water Levels Remain Above Normal at Kaupakalua Dam
Flood Watch in Effect Through Late Tuesday Night (Update: 3:17 a.m. 3.9.21)
A Flash Flood Watch continues for Maui, Molokaʻi, Lānaʻi, Kahoʻolawe, Kauaʻi, Niʻihau, and Oʻahu through late tonight.
The National Weather Service reports that deep moisture will remain over the state through tonight, bringing the potential for additional heavy rain that could lead to flash flooding.
“Additional heavy rainfall over windward Maui could cause the failure of the Kaupakalua Dam near Haʻikū, where water levels remain above normal,” the NWS advises. “If the Kaupakalua Dam were to fail, a life-threatening flood wave could occur downstream of the dam.”
According to the NWS forecast, significant flooding may occur due to the overflow of streams and drainages. Roads in several areas may be closed, along with property damage in urban or low-lying spots due to runoff. Landslides may also occur in areas with steep terrain.
The public is advised to be prepared to take action if a Flash Flood Warning is issued. If you experience heavy rain or rising waters, head to higher ground immediately.
A Flash Flood Watch means that conditions are favorable for flash flooding. Flash Flooding is LIFE THREATENING. Do not cross fast flowing water in your vehicle or on foot.
“Any additional heavy rainfall in the vicinity of the dam could lead to a short notice Flash Flood Warning for areas downstream of the Kaupakalua Dam, so residents are urged to closely follow the instructions provided by Maui Emergency Manangement officials,” the NWS states.
Flood Warning Until 3:30 a.m. for Maui (12:20 a.m. 3.9.21, 10:05 p.m. 3.8.21)
The National Weather Service has extended a Flash Flood Warning for the island of Maui until 3:30 a.m.
At 12:20 a.m. radar continued to indicate heavy rain over East Maui, from Haʻikū to Hāna to Kaupō, which includes the area upslope of the Kaupakalua Dam. Rain was falling at a rate of 1 to 2 inches per hour and area streams are running very high.
ʻOheʻo Gulch remains at a level that has produced serious flash flooding along the slopes of Haleakalā from Hāmoa to Kīpahulu in the past. Additionally, Hanawi Stream has risen to a level that has produced flooding along the Hāna Highway near Nāhiku in the past.
Heavy rainfall continues to develop just offshore East Maui and is expected to move onshore in the next couple of hours.