Kauai struck with record-breaking rainfall over the weekend, more expected this week | Global Resilience Institute

Unusually intense rainfall pummeled Hawaii’s island of Kauai over the weekend. The National Weather Service reported Monday that, in just 48 hours, some parts of the island were hit with upwards of 32 inches of rain. In Wainiha, the 24-hour rainfall total measured 19.54 inches, smashing the previous record of 16.7 inches set in January of 1969. CNN meteorologist Pedram Javaheri contextualized that figure, explaining, “That amount of rainfall would climatologically take nearly 18 months to fall in London and over 24 months to fall in Los Angeles.” As the University of Hawaii at Manoa illustrates, Kauai is not unaccustomed to rain, but such heavy precipitation in such a short period of time proved disastrous for the island.

Kauai Flooding
This image taken from video provided by the U.S. Coast guard shows flooding in Kauai’s Hanalei Bay, Hawaii, Sunday, April 15, 2018. Hawaii Gov. David Ige issued an emergency proclamation for the island where heavy rainfall damaged or flooded dozens of homes in Hanalei, Wainiha, Haena and Anahola. (Petty Officer 3rd Class Brandon Verdura/U.S. Coast Guard via AP)

The rain inundated many neighborhoods, tearing apart homes and triggering several mudslides along Kuhio Highway and severe flash flooding. The resulting damage to roads, bridges, and other infrastructure has made rescue efforts particularly difficult; responders have been forced to use jet skis and helicopters to conduct search and rescue operations where the destruction had isolated certain communities. By the end of the day Monday, over 340 residents had been either airlifted or otherwise evacuated from Haena and Wainiha on the north shore of the island alone.

Kauma Anahata, a resident of Kalihiwai Valley, described the flooded landscape to KHON2 News: “Before we knew it, [the rain] was to the roof of our vehicles, to the top of them. Our outside building had been just destroyed. The one blue Jeep just floated out of our carport. By then, the water was at least six feet high, and it’s like a raging river now, and we’re up on the stilts of our bamboo home just getting scared because there’s no way out at this point.”

All of Kauai, except for Keoniloa Bay, was placed under a water quality advisory. Some residents have been instructed to collect rainwater for non-drinking purposes. The Kauai Emergency Management Emergency Operations Center, Hawaii Emergency Management Agency, the U.S. Coast Guard, the U.S. Army, and the Honolulu Fire Department, among other actors, continue to conduct rescue operations and provide immediate support to area residents.

However, experts like Matthew Foster, a National Weather Service meteorologist based in Honolulu, worry that Kauai still has more to endure: “That low-pressure system that brought us all that weather this weekend is about 800 miles west of us now. It’s going to weaken and then it’s going to start moving back towards us [Wednesday]. It probably will be another round of heavy rain and potentially thunderstorms. The grounds are already very saturated, so it’s not going to take as much to bring the flooding back.” Estimates were later revised to push back the start of the rain to Thursday night local time and all of Hawaii remains on a flash flood alert.

Sources and Further Reading

Public Information Statement — National Weather Service

Hawaii rescuers airlift residents after floods, landslides on Kauai — CNN  

Hawaii’s Rainfall Patterns — University of Hawaii at Manoa

Rescue operations to continue in flood-ravaged areas of Kauai — Hawaii News Now

Unprecedented rainfall, landslides force water rescues and strand entire towns in Kauai — Accuweather

Landslides, floods, air rescues ongoing on Kauai — KHON2 News

Open Water Quality Advisories — Hawaii State Department of Health

Water Service Outage for Haena and Wainiha on Kauai — KITV News

Approaching storm system to threaten flood-ravaged Kauai later this week — Honolulu Star Advertiser

Kauai Struggles With Severe Flooding, As More Rain Is In The Forecast — NPR