An irrigation ditch carries water across a dry landscape in Pulehu in June. A state hydrologist expressed caution on Tuesday about stream flow as the county continues to deal with drought. “We have sufficient need at medium flow to meet existing and planned uses, but when we get into a drought situation, which we are increasingly presented with, whether it is seasonal or just out of nowhere — in the middle of wet season this year we had major drought — we come into problems,” Ayron Strauch said at a state Commission on Water Resources Management meeting on Tuesday. The Maui News / MATTHEW THAYER photo

If drought conditions persist on Maui, this could create an issue in meeting the needs of those who currently and will rely on East Maui streams for water, a state official said on Tuesday.

“We have sufficient need at medium flow to meet existing and planned uses, but when we get into a drought situation, which we are increasingly presented with, whether it is seasonal or just out of nowhere — in the middle of wet season this year we had major drought — we come into problems,” hydrologist Ayron Strauch said at a state Commission on Water Resources Management meeting on Tuesday.

But Strauch added that some of those issues can be mitigated by increasing usage of ground water for drinking water supply and/or increasing storage “to level out some of those highs and lows of availability” of water.

Strauch, who is with CWRM’s Stream Protection and Management Branch, was presenting his analysis of water uses from East Maui streams. No decisions were planned or taken on Tuesday.

In his analysis, Strauch factored in water that is used by the county Department of Water Supply, including for residential use; the state Department of Hawaiian Home Lands’ future projects in Pulehunui as well as the Keokea-Waiohuli area; and Mahi Pono and the Kula Agricultural Park, along with other farms.

The larger users projected would be Mahi Pono with 45.1 million gallons per day, the Kula Ag Park and other farms with 3.9 mgd and DHHL’s Keokea-Waiohuli project, which includes residential and farm lots, with 7.87 mgd.

East Maui Irrigation, which is owned by Alexander & Baldwin and Mahi Pono, is applying for a 30-year water lease for some East Maui stream license areas.

Strauch noted the declines in mean annual rainfall in Maui and declines in water availability in East Maui streams and irrigation ditches.

Strauch also said other proposed solutions to help with the water situation include rebuilding and/or replacing diversions to Waikamoi Flume and Upper Kula pipeline, mainly fixing existing leakages at points of diversion; increasing storage of raw water at all surface water treatment facilities; reestablishing the pipeline pump from Lower to Upper Kula; adding pipeline capacity from Waikamoi to Piiholo water treatment facility; and increasing groundwater monitoring to understand shifting recharge patterns on basal aquifer.

Darren Strand, vice president of agricultural outreach at Mahi Pono, said the company is moving forward with its farm plan and continues to plant crops.

This includes planting 3,200 acres by the end of this year and another 3,500 acres in 2023.

There already have 5,500 acres in pasture.

“We are on target to finish planting the just under 16,000 acres by 2025,” he said.

He added that “we are implementing a lot of practices for water efficiency on the farm.”

This includes using materials and techniques to have less evaporation in the fields, along with using moisture sensors and timing the irrigation to have water coming across in the ditch systems and going directly into the fields that need to be irrigated.

They upgraded other irrigation systems so that the correct amount of water is applied to the right areas near the trees.

Mahi Pono is also pumping some ground water, doing so several days a week, and is using about 5 million gallons of water per day from that source.

Currently they are in the middle of harvesting watermelon. There are also pumpkins, carrots, sweet potatoes, beets, kale, lettuces and onions, and some first plantings of citrus trees are beginning to bear fruit.

He said 100 percent of what they have harvested to date has been sold in the state.

“We feel like we have been making a significant impact on local food production,” Strand added.

While there was no action scheduled on the analysis, some testifiers used the mention of East Maui water as a springboard to get their message out about pending in-stream inflow standards.

Tara Apo-Priest said she was testifying in support of setting “generous meaningful in-stream in flow standards” for 12 streams from Hoolawa to Kolea in East Maui.

“It is so important these streams are allowed to flow through every level of the watershed being an integral part of our ecosystems from mauka to makai,” she said.

Apo-Priest said that “community voices” from those who live next to the streams also need to be considered.

She said some of these residents are not connected to the county water system, but do not need to truck in water during drier times.

She added that in the past Mahi Pono “has overestimated” the amount of water it needs for diversified agriculture, and she also pointed to the “wasted water” via transmission and storage by the East Maui system.

“Reducing the amount of wasted water should be a number one priority,” she said. “Less water wasted means more water available for all needs.”

* Melissa Tanji can be reached at mtanji@mauinews.com.