HONOLULU (HawaiiNewsNow) - Last night's sudden rainfall had nowhere to empty out but the H1 freeway, and at the worst time, just before early morning traffic. It triggered a landslide.
"You put that amount of rain on any surface you're going to have a lot of run off," says Kevin Kodama of the National Weather Service.
A double whammy is to blame for the traffic nightmare for thousands of eastbound commuters on the H-1 freeway.
The National Weather Service says two storm systems merged creating intense downpours overnight. All that water had nowhere to go except onto the freeway.
"The side of the mountain didn't give away. It wasn't that kind of a landslide. But it was all of this water that kind of rushed over our property and then formed a groove and then hit the highway and just created this huge mud mess," said Dan Meisenzahl spokesperson for the State Department of Transportation.
Just feet from the Liliha over-pass, the water accumulated on School Street and found a small divot which acted like a funnel leading directly to the highway.
"We got the first call around 2:57 am, when our crews showed up thankfully the fire crews were there. They had started to spray the mud down which had reached all the way across all lanes of the freeway," Meisenzahl said.
Which resulted in this, commuters backed up for miles, with nowhere to go.
"We brought in some equipment as well, a water truck, a dump truck, a bobcat. We cleared away, one dump truck load of mud. Unfortunately it was a lot of work and it took us a little bit of time to get it done."
Nearly four and half hours later the DOT crews were able to open up all lanes again.
The National Weather Service says the severe weather could have been worse.
"Luckily they were moving enough so that they didn't stick to any particular spot and although we had a lot of run-off it didn't match some of the bigger floods like Manoa flood or the Mapunapuna flood," said Kodama.
"We're checking the area, if there is anything we can do to prevent this from happening again we're definitely going to do it," said Meisenzahl.
Kodama says the rain gauge in the back of Moanalua valley showed 7 inches of rain fell during a 24 hour period.