The time to prepare for flash flooding is when skies are blue
It began with three long buzzes and a long beep, followed by an ominous computerized voice. The National Weather Service Emergency Alert broadcast an emergency evacuation order for the area downstream of the Kaupakalua Dam, described as “in imminent danger of failure.”
Between 7 a.m. and 3 p.m. on Monday, March 8, 13.2 inches of rain had fallen in the Haiku area. It swelled streams into raging rivers and ripped through gulches and riverbeds, sweeping away rocks, trees, structures and everything else in its path. The flood, described by kama’aina as “unprecedented,” closed roads, ruined bridges and damaged or destroyed at least 17 homes.
As soon as the evacuation was announced, the Maui Fire Department received more than a dozen calls from Haiku residents needing help geting out of harm’s way. Five crews from the Paia, Makawao and Wailea stations, plus Rescue 10 and Hazmat 10 responded. Thanks to the county’s highly trained, professional first responders, there was no loss of life or major injury.
Maui County is prone to flash flooding because our steep mountainsides and extensive stream systems make perfect pipelines for huge volumes of rainwater to rush downhill at high speeds. Flash floods can happen at any time but are common during Hawaii’s wet season from October through April.
Honolulu’s National Weather Service office reports most flash-flood deaths in Hawaii happen when drivers attempt to cross rushing streams. Vehicles stall and folks get trapped inside. Just one foot of water can eliminate steering control and two feet of rushing water will easily carry most vehicles away. Never try to drive, or walk, across floodwaters.
Hikers, listen for distant thunder and watch for dark mountaintop clouds; both are signs that runoff could be headed your way. If you see rapidly rising water, immediately head for higher ground. If you feel you must cross a flowing stream to leave, turn around and go another way or wait until flooding subsides.
Herman Andaya, administrator of the Maui Emergency Management Agency, says that being informed and prepared can keep you safe. All Maui Nui residents should sign up for the county’s Maka’ala Alert System to get emergency alerts in real time. Knowing a flash flood watch is in effect is valuable safety information.
Maka’ala sends alerts tailored to the subscriber’s location using Everbridge’s SMARTWeather service. Sign up is free and easy–just visit https://www.mauicounty.gov/70/Emergency-Management-Agency and scroll down to Maka’ala Alert System.
In case of an imminent safety threat, Wireless Emergency Alerts automatically go to mobile phones in affected areas. There is no need to sign up for this service. Those without cellphones should keep a battery-operated radio nearby for emergency broadcast information.
In life-threatening situations, outdoor warning sirens will sound. Sirens are designed for tsunami coastal evacuations but can be used in other emergencies. Warning sirens will blare a solid, steady tone for three minutes. If you hear an outdoor warning siren, immediately tune your radio to a Maui County station for emergency information and instructions.
Even after the danger of active flooding has passed, effects can linger. In the aftermath, local responders may not be able to reach you immediately. If roads or bridges are washed out, electric lines are down or debris is blocking roadways, it could be a long time before you can leave or help to come to you. That’s why MEMA recommends every Maui County household prepare to shelter in place for at least 14 days.
Disaster preparedness includes a household emergency communications plan, familiarity with nearby shelters, a home emergency kit stocked with sufficient water, nonperishable food, mechanical can opener, flashlight and radio that don’t need electricity, extra batteries, solar cellphone charger, personal hygiene needs, first aid kit and a whistle to signal first responders.
Pre-pack an emergency evacuation kit with copies of important documents sealed in a plastic bag, medications, extra clothing, sleeping gear, personal hygiene products and nonperishable snacks. For detailed disaster preparation guidance, visit www.mauicounty.gov/DocumentCenter/View/119395/Disaster-Preparedness-Guide-for-Maui-County.
The time to prepare is now — when skies are blue. Please don’t wait. Most natural disasters happen quickly and without advance warning. Be informed, be prepared and be safe.
* “Our County,” a column from Maui County Mayor Michael Victorino, discusses county issues and activities of county government.