The state has recently redefined water as a public resource. Now it’s going to start studying how best to use and protect that resource.

In September 2008 and May 2010, the state Commission on Water Resource Management (CWRM) set standards for how much water must be left in 21 streams in East Maui. Part of those decisions involved setting up programs to manage and evaluate how the streams are used.

One such program is now one step closer to becoming a reality.

At its monthly meeting Thursday, the commission authorized new Chair William Aila to partner with the U.S. Geological Survey (USGS) on a $130,000 efficiency study.

“For over a century, the East Maui Irrigation Company’s (EMI) surface-water diversion systems have diverted water from streams in east Maui, Hawaii for large-scale sugarcane cultivation by Hawaii Commercial and Sugar Company (HC&S) and for general agriculture and domestic use through the public water system(s),” states a submittal [pdf] from commission staff regarding the program. Both EMI and HC&S are under the corporate umbrella of Alexander and Baldwin, one of Hawaii’s oldest and largest land holding companies.

“Results from this study will be useful for determining system efficiency and will aid in the management of surface-water resources in east Maui.”

The 18-month study will evaluate water seepage rates from 75 miles of East Maui Irrigation Company’s ditches and tunnels, according to the submittal. It will do so by measuring seepage from various sections of three categories of ditch construction — lined with concrete or cut stone; partially lined; and unlined (dirt only) — and determining how many miles of each category are used. From that data, the study will be able to estimate how much water is lost — or gained — by the irrigation system.

Presumably, the commission will weigh the results of the study as it considers permanent instream flow standards or amendments to the flow standards in the future. If the study finds the system is inefficient, it could undermine arguments in favor of offstream water uses as the commission balances agricultural interests and health of the streams’ ecosystems.

EMI will be paying for one-third of the project, but it won’t be an even three-party split. At the meeting, water commission staff said the USGS can’t be counted on for its share of the funding. So the balance — a little less than $90,000 in all — will need to be included in the Department of Land and Natural Resources budget or otherwise allocated by the Hawaii Legislature.

“HC&S and EMI are in full support of the study proposal that was approved by the CWRM this week,” HC&S General Manager Chris Benjamin said in a written statement. “We, in fact, worked closely with CWRM staff and USGS representatives to develop the proposal that was presented. We have already agreed to pay our share of the study, and will assist in the implementation of that study.

“The EMI system collects, transports and delivers water to meet the needs of residents, farmers and ranchers in Upcountry Maui, not only HC&S,” Benjamin said. “The information from this study could be of benefit to many.”

The study’s results are expected to be published in July or August 2012.

DISCUSSION: What do you expect the study will find after its review of East Maui’s ditch system? Join the conversation.*

About the Author