The Environmental Court set the cap on Tuesday after reviewing water usage data from A&B’s subsidiary East Maui Irrigation Co., according to the Sierra Club of Hawaii, which is awaiting a decision on the contested case it brought forward over the 2021 and 2022 revocable permits for a dozen East Maui streams.

The new cap will be in place for the next 45 days or until the state Board of Land and Natural Resources makes a decision on the contested case.

“This is a big deal. This goes to show exactly how important the documentation of water usage is and why we’ve advocated for such data for years,” Wayne Tanaka, Sierra Club of Hawaii director, said in a news release Thursday. “Over the next 45 days, 225 million gallons of water will no longer be at risk of diversion to fill A&B’s leaky reservoirs and aging infrastructure. This water will stay in its rightful streams and go on to supply much needed nourishment to native ecosystems and downstream communities.”

A&B did not comment directly on the reduction in permitted water diversions but applauded the decision to allow the permits to continue.

“We are pleased the Environmental Court acted to extend the water permits, ensuring that important water supply to Maui residents, farmers, businesses and public facilities would not be interrupted, while the Board of Land and Natural Resources’ (BLNR’s) decision on the permits is finalized,” an A&B spokesperson said in an email on Thursday afternoon. “The BLNR issued its proposed decision on the permits on the same day the court took action.”

Environmental and Native Hawaiian advocacy groups have waged yearslong legal battles with the state and A&B over East Maui streams, which the company diverted for over a century through a complicated ditch system to feed sugar plantations in Central and Upcountry Maui.

The revocable permits, which were supposed to be temporary but allowed to continue for years, have fueled a large portion of that contention. In 2016, a First Circuit Court judge ruled that the annual rollover of permits violated state law, but the practice was allowed to continue after the state Legislature passed a bill extending it through 2019.

A June 2019 decision by the state Intermediate Court of Appeals to overturn the 2016 ruling reopened the door for A&B to seek revocable permits, and in October 2019 the Board of Land and Natural Resources approved another one-year permit for the company to continue diverting water from East Maui. The board approved permits again in November 2020.

At the time, the Sierra Club’s request for a contested case over the permits was denied, a decision the advocacy group challenged in court.

In May, First Circuit Judge Jeffrey Crabtree ruled that the board violated the Sierra Club’s rights by refusing its request for a contested case hearing. Crabtree went on to cut EMI’s permitted water diversions from 45 mgd to 25 mgd in July.

* Colleen Uechi can be reached at cuechi@mauinews.com.