Red Hill, One Year Later: A look 140 feet underground ― at a pristine water source at risk

The Board of Water Supply’s Halawa Shaft is part of the public’s water system and it’s still pristine. But it’s less than a mile from the Navy’s Red Hill Shaft.
Published: Nov. 22, 2022 at 4:07 PM HST|Updated: Nov. 23, 2022 at 8:12 AM HST
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HONOLULU (HawaiiNewsNow) - The Board of Water Supply’s Halawa Shaft is part of the public’s water system and it’s still pristine. But it’s less than a mile from the Navy’s Red Hill Shaft, which was contaminated last year.

That’s why it’s been shut down since last year ― to protect it.

You get to Halawa Shaft through an unimpressive building.

But once inside, you catch a ride on a cable car to the shaft 140 feet underground. HNN traveled to the shaft with Ernie Lau, Board of Water Supply manager and chief engineer.

The BWS shut down the Halawa Shaft to protect it from contamination. Ernie Lau takes us inside the facility to explain what's at stake.

The cable car leads to a different world ― and another era.

In 1940, with war on the horizon, Honolulu urgently needed water but supplies were strained. The war would mean more people coming to the island.


Board of Water Supply crews started construction of the Halawa Shaft on December 6, 1941, a day before the Japanese attack on Pearl Harbor. Workers witnessed the planes as the United States’ entry into conflict.

The dangerous work later resumed with men tunneling through rock in waist-deep water.

Few people get an up-close tour of this precious resource.

“We are actually walking in the escape tunnel,” Lau explains, on the tour. “The workers could actually get into this tunnel to avoid being drowned.”

The shaft is Oahu’s largest water source.

“Behind me are three large pumps, a pump that can pump 7,000 gallons every minute,” Lau says.

The Halawa Shaft is controlled remotely by computer, but it can also be manually controlled by hand-wheels that operate the valves.

Up until the Navy’s water crisis, Halawa Shaft supplied 20% of Honolulu’s water needs from Halawa to Hawaii Kai.

But on Dec. 3, 2021, Lau announced he was shutting down Halawa Shaft indefinitely over fears water leaving the shaft would pull contamination from the Navy’s underground fuel facility and into the civilian supply.

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“I didn’t know whether or not the fuel had migrated in the aquifer to the point where it would start pumping up into Halawa Shaft,” he said, adding there is no timeline for the shaft being put back into service.

He won’t turn it back on “until I can be darn sure” the shaft is safe from contamination.

He added, “Actually hearing the silence in Halawa Shaft, of the pumps not running, makes me really sad because this is one of our main water sources that we depend on for Honolulu,” he said.

At his news conferences, emotions from the soft spoken engineer have stirred the community.

It was Lau who eight years ago, in a letter to the Navy, warned that “a small release of several thousand gallons could produce a groundwater plume that impacts the Navy’s Red Hill shaft water supply,”

It was a prediction of the current disaster.

Back at Halawa Shaft, Lau took HNN to a viewing area over the water supply.

Lights inside give it a vibrant aqua hue. The water clean enough to drink right there.

The beauty of the water, Lau said, is a reminder of the need for its protection. “For me, it’s everything. It’s the essence of life for our community,” Lau said. “Without this clear, clean water, we can’t survive on this island.”

As part of a special series, “Red Hill: One Year Later,” Hawaii News Now is taking an in-depth look at an environmental and public disaster whose impacts continue to be felt. See more coverage here.