NEWS RELEASE: Wahiawā Dam Preparedness And Evacuation Information Ahead Of Incoming Tropical Storm Moke
2026-016
August 21, 2026
HONOLULU – As the state prepares for anticipated heavy rains and potential flooding from another approaching tropical storm, the Hawaiʻi Emergency Management Agency (HIEMA) is urging residents in the Wahiawā area to take necessary precautions, especially those living near or downstream of the Wahiawā Dam.
“Safety is our top priority and understanding how to prepare for possible evacuations is critical,” said HIEMA Administrator David Lopez.
Status – Wahiawā Dam
As of this morning, Friday, August 21, the water level in the Wahiawā reservoir is 77.5 feet. The Wahiawā Dam can operate up to water levels of 90 feet. Since last week, the state Agribusiness Development Corporation (ADC), the dam owner, has been discharging water at the maximum safe rate.
The contractor for the Wahiawā Dam Rehabilitation Project, Goodfellow Bros. LLC, has begun to install an Aquadam bladder, which will raise the height of the dam embankment by 1.5 to 2 feet. This will effectively increase the dam’s spillway capacity and help prevent water from overtopping the dam.
Speaking on behalf of the Department of Land and Natural Resources (DLNR) Dam Safety, which monitors regulated dams, Board of Land and Natural Resources Chairperson Ryan Kanaka‘ole said, “We want everyone to know that our teams have been working tirelessly for the past several weeks with dam owners and state and county agencies involved in emergency response. “DLNR will continue to issue critical information during the storm.”
Alert Levels
Based on multiple safety factors and the anticipated time required for emergency responders and the public to safely evacuate the inundation areas surrounding Waialua and Haleʻiwa, the ADC has established several elevation triggers in its Emergency Action Plan (EAP) to notify DEM:
| Alert | Definition |
| 82 feet: Non-failure Alert | An unusual event. |
| 84 feet: Potential Failure | High water, possible incident. |
| 86 feet: Imminent failure emergency level | High water level, dam could be overtopped. |
The County DEM will determine when warnings should be issued.
Additionally, the National Weather Service may issue flash flood warnings, which may or may not be related to the ADC’s notifications.
Possible Flooding Unrelated to Wahiawā Dam
Some areas from Waialua and Haleʻiwa, including Otake Camp, are situated in high-risk flood zones. These areas are prone to flooding during any heavy rains, as water flows down the north and northeast flanks of Waiʻanae Mountain Range and from the Mokulēʻia Forest Reserve on its way to the ocean.
Residents should understand their flood risk in these areas may not solely be from the discharge of Wahiawā Reservoir. A good way to confirm your flood risk is the flood hazard assessment tool. (https://fhat.hawaii.gov/)
Be Prepared
In anticipation of heavy rainfall, it is important for residents to be aware of potential changes to water levels and the possibility of controlled releases from the dam. As storms intensify, the likelihood of rapid increases in water levels can lead to dangerous flooding. Understand the importance of storm conditions and the potential impacts of rising waters from nearby dams.
What Residents Should Know:
- Evacuation Zones: Residents living in low-lying areas near the Wahiawā Dam are encouraged to familiarize themselves with designated evacuation routes. If you feel threatened by the approaching storm, consider self-evacuating to a safer location. Should authorities issue an evacuation order, it is crucial to comply promptly for your safety and well-being.
- Know if you are located in an evacuation area for Wahiawā or other dams in the area, see the City and County of Honolulu Oʻahu Dam Evacuation Planning Tool: https://experience.arcgis.com/experience/d9e2e0555cce49faa0917ba7fec99349
- Potential Flooding: Experts predict significant rainfall, which could lead to flash flooding in nearby streams, rivers and low areas. Pay attention to weather updates and heed any warnings from local officials.
- Communication: Stay informed through local news channels, the National Weather Service and community alert systems – such as HNLAlert. Ensure your cell phones are charged and have battery backups available.
- Preparation Tips: Prepare an emergency kit with essentials, including water, non-perishable food, first-aid supplies, medications, flashlights, batteries and important documents; plan for pets and ensure you have provisions, including food, water and any necessary medications; make sure your vehicle is fueled and ready for travel. Consider having a full tank of gas in case you need to evacuate. Be prepared to evacuate on foot.
“As we brace for the impending storm, I want to emphasize the importance of preparedness and community resilience,” said Lopez. “Local, state and federal officials are working diligently to ensure safety measures are in place, but we also need the cooperation of every resident. Please take this opportunity to prepare your homes and families, stay informed and look out for one another. Let’s navigate through this storm safely.”
By taking proactive measures and understanding the potential consequences of rising waters, residents can better protect themselves and their property.
For information on disaster preparedness and to find your designated evacuation zones, we encourage residents to visit ready.hawaii.gov.
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Media Contacts:
S. Kīelekū Amundson
Communications Director
Phone: 808-733-4300 Ext 522
Email: [email protected]
Andrew Laurence
Communications Director
State of Hawaiʻi Department of Land and Natural Resources
Phone: 808-587-0396
Email: [email protected]