Hydrologists from the state Commission on Water Resource Management say this winter’s drought conditions will worsen considerably across the state if there is no significant rainfall between now and the start of the dry season.

Hydrologists are seeing record-low water levels not only in Kawaikoi Stream, which drains a portion of the Alakai Plateau on Kauai, but also in some East Maui streams, according to a Department of Land and Natural Resources release.

“Kawakoi Stream is flowing at record low flows for the last seven to nine months. Right now, we’re at about 20% of normal flow for this time of year, which does not bode well for the dry season. This is typically the wettest part of the year,” explains Dr. Aryon Strauch, CWRM’s lead hydrologist, in the release.

Strauch says they are seeing record-low flows in the roughly 109 years of recorded history for Kawaikoi and 105 years in some streams of East Maui. “But we’ve not seen low flows like this across the state to this extent ever before.”

Some streams are already completely dry, says Strauch, which is affecting water availability for drinking water supplies, traditional and customary practices, and agriculture.

Mike Faye (pronounced “fi-yah”), a water manager with the Kekaha Agriculture Association on Kauai, will soon be faced with distributing a dwindling supply of water to ag users, according to the release. And unless conditions improve, some of them will “be left high and dry.”

“Our role is to take care of the infrastructure, which consists of two ditch systems that come out of the mountains in Kokee— the Kekaha ditch and the Kokeeditch,” stated Faye.

The association also operates and maintains two hydroelectric plants — Mauka Hydro in Waimea Valley and Waiawa Hydro that was built in 1908 — along with 30 miles of power lines and 30 miles of roads. If water flows continue to drop, the power produced by the plants could stop along with water delivery to the nine licensees located on mauka lands above Kekaha Mana Plain. It’s a total of 13,000 acres that formerly supported Kauai’s plantation-era sugar industry.  The release states that the state’s Agribusiness Development Corporation licensed the agriculture tenants.

“One of the benefits of having long-term data sets is being able to talk about the severity of the drought conditions being observed relative to 100 years of record, and by explaining that these are unprecedented flows,” said Strauch.

Lead hydrologist Dr. Aryon Strauch says they are seeing record low flows in some East Maui streams. (Photo courtesy of the Department of Land and Natural Resources)

“For the last nine months, we’ve only had maybe 12 days of peak flow conditions, which is very unusual, and we can compare that to a normal year, where we might have 60 days of peak flow conditions. The availability of water is just severely limited. Despite the water flowing in the stream, it’s just not flowing very much,” Strauch said.

The CWRM team uses sophisticated instruments and data from permanent stream flow measurement stations to monitor regularly conditions of 80 waterways statewide. They say the outlook is especially bleak in west Kauai and in east and west Maui.

“Honokohau Stream in West Maui, the medium flow for this time of year is about 20 cubic feet per second (CFS), or about 12 to 13 million gallons per day,” Strauch said. Last week, the stream was flowing at eight to nine CFS, or five and a half to six million gallons per day, which is a third or 25% of normal flows. Recent rains have improved the Honokohau Stream flow to 11.8 CFS.

Iao Valley’s Wailuku River also saw improved stream flow over the last week, from 15 CFS to 22 CFS.

A dry stream bed in Maui. Maui County has already issued water conservation notices to prepare for the summer. (Photo courtesy of the Department of Land and Natural Resources)

“Normal flow is about 25 and again, these flows are supplying water for drinking water supply,” said Strauch. “They’re supplying water for in-stream values, and it becomes a real challenge to manage water demand and water availability when we’re trying to protect a number of competing public trust uses.”

The usually rain-rich East Maui is also experiencing record-breaking low stream flows. Maui County has already imposed water conservation restrictions due to the current water shortage and looking toward the summer and into the next wet season.

Strauch concluded, “Obviously this impacts people who are directly reliant on the streams. But long-term agriculture and other off-stream uses that may not be the priority of the public trust uses of water, they’re going to suffer, because we just don’t have enough water right now to meet the demands.”

Strauch is hoping late winter rains will improve the water situation statewide, but if that doesn’t happen, he says water conservation will be key.