Almost 99% of Hawaiʻi’s drinking water comes from water stored underground in aquifers across the islands, and groundwater supplies are impacted by changes in both land cover and climate. The NSF funded ‘Ike Wai (knowledge of water) Project at the University of Hawaiʻi spans multiple scientific disciplines and connects researchers to better understand how future land use and climate change might change groundwater recharge, and how, this in turn would influence water management decisions.. Following the stakeholder-driven approach used in the Pacific RISA Maui Groundwater Project, we worked with the State Department of Forestry and Wildlife, the Koʻolau Watershed Partnership, the City and County of Honolulu, and the State of Hawaiʻi Department of Planning to come up with a set of possible futures of conservation, urban, and agricultural land in the most heavily utilized aquifer on Oahu: the Pearl Harbor aquifer. Pacific RISA co-lead Laura Brewington developed the future land cover scenario maps as inputs to the groundwater model, which was run by the US Geological Survey. The scenarios reflected both transit-oriented development (dense development around the projected corridor for the Honolulu light rail project) and sprawl-type development (a business-as-usual approach), in combination with varying degrees of agricultural intensification or reduction and native forest protections.

Sustainable yield estimates and resulting differences in replacement costs were estimated for the six land cover scenarios crossed with two water demand scenarios under a potentially drier future climate. The results showed that both climate and land cover change were important drivers of changes in groundwater recharge. The degree of watershed protection, through preventing the spread of high-water-use, invasive plant species, had a much stronger impact than urban development. Specifically, protecting all of the aquifer’s native forests increased sustainable yields by 7–11% (30–45 million liters per day) and substantially decreased treatment costs compared with no forest protection. Furthermore, the greatest benefits to recharge occurred in the upper elevations of the watershed, which impacted the Waipahu-Waiawa and Waimalu subaquifers most substantially.

Running this through the groundwater optimization framework, we also found that watershed protection could increase sustainable yield by 8-12 MGD, which translated into $26-40 million in annual savings in water supply costs after 50 years. Today, the Pearl Harbor aquifer area is a mix of urban areas, military zones, agricultural lands (both active and fallow post-plantation), and conservation areas. The aquifer also supports numerous culturally and ecologically important springs, which have been rapidly declining since the rise of the plantation era in the mid 1800s. Nevertheless, there are still many important areas that rely on springs, including loʻi kalo systems, wetlands, and the Sumida watercress farm who were partners in this research. Our study found that even when confronted with the impacts of climate change, native forest protection in Hawaiʻi’ can play an important role in reducing the combined effects of land-use and climate change on groundwater resources.

Resources

• Click here to visit the University of Hawaiʻi ‘Ike Wai Project page
• Bremer, L.L., Elshall, A.S., Wada, C.A., Brewington, L., Delevaux, J.M.S., El-Kadi, A.I., Voss, C.I., & Burnett, K.M. (2021). Effects of land cover and watershed protection futures on sustainable groundwater management in a heavily utilized aquifer in Hawaiʻi (USA). Hydrogeology Journal. http://dx.doi.org/10.1007/s10040-021-02310-6

Featured image: Sumida Farms and the University of Hawaiʻi ʻIke Wai team. Credit: University of Hawaiʻi

Workshop participants included community freshwater managers and planners, decision makers, and climate experts from American Samoa, Samoa, Fiji, Tonga, and Hawaii. They represented local utilities American Samoa Power Authority (ASPA), the American Samoa Environmental Protection Agency (ASEPA), the National Weather Service, Meteorological Service experts, and local and regional resource and environment agencies (SPREP, etc). Using a climate scenario dialog framework, participants conducted interactive climate stories that contributed to the exploration of future best practices to preserve freshwater resources and minimize the impacts of drought, with an emphasis on the upcoming ENSO event. A key point raised was the need for improvement in inter-agency cooperation and communication to raise awareness of the state of knowledge of climate science, impacts, and adaptation and available climate and weather service products and services to support climate adaptation planning, disaster risk management, and “win-win” strategies for freshwater management.

At the workshop, Dr. Brewington presented the initial results of a study led by Pacific RISA Project Specialist Richard Wallsgrove on the Climate Adaptivity of Freshwater Regulations in American Samoa. The presentation evaluated the effectiveness of American Samoa’s adaptive policies and planning tools next to the criteria of being forward-looking, adaptive, integrated, and iterative. It also suggested 9 opportunities in which adaptive capacity could be improved in American Samoa. Also during the workshop, Chris Schuler, University of Hawaii graduate student, described the status of a groundwater model for the island of Tutuila being developed at the UH Water Resources Research Center (WRRC). The potential applications of the groundwater model include sustainable yield estimates, well-siting and future development, contamination potential, and climate change adaptation. Other presentations by the Fiji and Samoa Meteorological Services, SPREP, NWS, and ASPA contributed greatly to the enrichment of the climate scenario dialog.

Through the collaborative efforts of the workshop participants, local knowledge was combined with specialist technical advice to identify accurate, timely and regionally-relevant content that helps to preserve fresh water resources and minimize the impacts of drought. As a result of the dialogue, the user community is better informed about the current state of knowledge of climate variability and its impacts, and the provider community is better informed about what problems and questions are most relevant and better able to match products and services to user requirements. Click here for more information on the Pacific Climate Information System (PaCIS) Drought Dashboard.

Pacific RISA research assistant Duncan McIntosh recently attended the “Pacific Islands Climate Services Dialog: Preserving Freshwater Resources and Minimizing the Impacts of Drought” workshop which was held 23 to 25 April, 2014 in Majuro, Republic of the Marshall Islands (RMI). The U.S. National Oceanic and Atmospheric Administration (NOAA), through the U.S. Agency for International Development (USAID), is conducting a series of activities to enhance scientific and technical capacity to support climate change adaptation in the Pacific Small Island Developing States (PSIDS).  These activities include the development and delivery of new or enhanced products and services that focus on climate issues critical to the region and respond to unique user needs.

To support RMI decision makers who are preparing for and responding to climate conditions that affect fresh water resources, a team of researchers is gathering relevant resources that may provide early warning and descriptions of potential impacts to the RMI area in one place – a web-based “dashboard” with real-time updating. This effort is a collaboration between Pacific Climate Information System (PaCIS), Pacific RISA, the Pacific Islands Climate Science Center (PICSC), and the Pacific Islands Climate Change Cooperative (PICCC), with support from USGS, University of Guam, Pacific ENSO Applications Center (PEAC), and NOAA.  Product development will focus on the collection and aggregation of information from disparate sources and the tailoring and transformation of that information so that it is specific to sector and locale, and targeted to the nature and timing of decisions. Pacific RISA supported the development of the drought dashboard prior to the workshop by conducting interviews with high-level decision makers in RMI who manage freshwater and community during drought, and compiling the results into a report identifying key characteristics of the stakeholders, their climate-sensitive decisions and information needs, and the broader contextual factors that influenced drought management decisions.  A semi-structured interview protocol guided discussions with interviewees to identify their main responsibilities and duties, specify key decisions affected by climate variables, determine current understanding of climate impacts and use of climate information, and identify climate information needs for managing drought and fresh water resources.  At the workshop, key findings of the Pacific RISA report were presented to the plenary and utilized as a spring board to initiate discussion of climate stories from the local decision-makers’ perspectives.

At the workshop in Majuro, local knowledge was combined with specialist technical advice to identify accurate, timely and regionally-relevant content that helps to preserve fresh water resources and minimize the impacts of drought.  As a result of the dialogue, the user community is better informed about the current state of knowledge of climate variability and its impacts, and the provider community is better informed about what problems and questions are most relevant and better able to match products and services to user requirements.  Click here to view the workshop proceedings.

A persistent drought in the Republic of the Marshall Islands (RMI) has reached a severe level, affecting 8,000 to 10,000 people of the northern atolls. There has been little rainfall in the northern Marshall Islands this year, and well water is turning brackish, making it unsafe to drink or use for crop irrigation. With no alternative source of fresh water, the Marshallese Government has declared the drought a national disaster. In addition to the drinking water shortage, island communities are facing the threat of communicable disease as well as food shortage, as many subsistence food gardens have suffered from the drought.

Clint Simpson of the National Weather Service Office in Guam told Radio New Zealand that a high pressure system is lingering over the Central Pacific, causing the dry weather conditions. Typically, dry spells are offset by Trade Wind showers, but not this time. Forecasters warn that the drought is likely to get much worse in the weeks to come, as no rain is forecast for the near future. In fact, the drought may last through July, or possibly longer.

The Marshall Islands’ Foreign Minister, Phillip Muller, reports that the government conducted an assessment of the impacts on communities and says that the situation is “quite dire.” The United States government is making their own assessment, and if the need is found to exceed one million dollars, the US President will allow for additional aid to the country.  The US has already delivered solar-powered reverse osmosis equipment that can supply a small amount of water (about 300 gallons daily), but it will not be enough for island populations. The Australian government has also provided US$100,000 in emergency desalinization units. The United Nations recently sent an emergency grant and an assessment team to the RMI. Jens Laerke, a spokesperson for the UN Office for the Coordination of Humanitarian Affairs said, “The lack of clean drinking water is of acute humanitarian concern, and children are particularly vulnerable.”

While the water shortage is worsening for families in the northern islands, atolls south of the capital of Majuro have received enough rain to be spared dangerous water shortages. The large municipal reservoir at the Majuro Airport held 20 million gallons as of mid-April, which is a little over half of capacity.

The latest issue of the Pacific ENSO Applications Climate (PEAC) Center’s quarterly newsletter, released in early May, reports that rainfall should slowly build back to normal across the RMI, starting with Majuro in May, Kwajalein by June, and into the drought-stricken northern islands by July. Download the full newsletter, with climate conditions and outlooks for each Pacific Island group, here.

References

Australia To Assist RMI Amidst Severe Drought Conditions.  Radio Australia. 6 May 2013. Available from http://pidp.eastwestcenter.org/pireport/2013/May/05-07-10.htm.

The Marshalls Islands has declared a state of disaster in the island nation’s North due to the prolonged drought. Radio Australia. 10 May 2013. Available from http://www.radioaustralia.net.au/pacific/radio/program/pacific-beat/marshall-islands-declares-national-drought-disaster/1129120.

Marshall Islands drought to get much worse – forecaster.  Radio New Zealand, International.  7 May 2013. Available from http://www.rnzi.com/pages/news.php?op=read&id=75859.

UN disaster assessment team arrives in drought-affected Marshall Islands. UN News Centre. 10 May 2013. Available from http://www.un.org/apps/news/story.asp?NewsID=44871&Cr=drought&Cr1=#.UY2cM0rihYU.

The Pacific ENSO Applications Climate Center. Pacific ENSO Update,  2nd Quarter, 2013 Vol. 19, No. 2.,  issued May 2, 2013. Available from http://www.prh.noaa.gov/peac/peu/2013_2nd/PEU_v19_n2.pdf.

Cover photo:  Namorik Atoll, in the Republic of the Marshall Islands. Courtesy of Darren Nakata.

The Hawai‘i  legislature is currently reviewing measures that would provide reliable, dedicated  funding to protect the state’s important watershed areas, with the  long-term goal of ensuring a sustainable supply of freshwater for Hawai‘i ’s residents, agriculture, businesses, and ecosystems.  In this legislative session, the Hawai‘i  Department of Land and Natural Resources (DLNR) hopes to ensure funding for the next 10 years for actions that would double the area of protected watershed land in the state.  Two pieces of legislation currently on the table have the potential to move DLNR, and Hawai‘i, toward that goal.

The essentials

“Bag bill”

One proposed measure would establish a fee of 10 cents on each single-use check out bag (including paper and plastic) distributed in the state to directly support the DLNR’s watersheds plan.  A large portion of the collected fees would be deposited into the state’s Natural Areas Reserve Fund, specially designated for expanding watershed protection.[1] If passed, the “bag bill” would take effect on July 1, 2013. In the first six months, up to 20% of funds collected may be used by local businesses to cover the cost of implementing the bag fee, and thereafter businesses could retain up to 10% for this purpose.  Annually, an amount will be reserved for administering and enforcing the fee. The fee would take effect on July 1, 2013, and would provide near-term funding that is critically needed to begin implementing the state’s watershed protection plan while the DLRN actively develops long-term funding streams.  Meanwhile, the state would dramatically cut the number of single-use bags distributed.  If disposable bag use does not decrease by 75% by July 2017, the bill specifies an increase in the fee to 25 cents per bag beginning in 2018.

Conveyance tax bill

A second measure, relating to the real estate conveyance tax, presents another method to secure funding for critical watershed protection.  Senate Bill 1166 and its companion, House Bill 935, would raise the conveyance tax on sales of certain real estate valued at $2 million or more and would increase the portion of the tax going to DLNR watershed projects.  Specifically, the bill would raise the amount of tax revenue deposited into the Natural Area Reserve Fund from 25% to 35%.  Additionally, The bill expands the specified uses of conveyance tax funds to explicitly include invasive species control and projects undertaken in accordance with the DLNR’s watershed plans to protect and restore Hawai‘i’s source of water.

Why watersheds?

There is urgency to the DLNR’s push to secure funding in the 2013 legislative session that arises from concerns over declining freshwater availability and the effects of a changing climate on native forest ecosystems, and ultimately Hawai’i’s freshwater supply.

It is clear that healthy forests provide immense monetary benefits and essential services. Ground water is the main source of drinking water for Hawai‘i residents.  Hawai‘i ’s forests play an important role in recharging aquifers by intercepting rainwater and cloud fog and delivering that water into the ground. While native forest plants accomplish this effectively, increasingly widespread invasive species hinder the replenishment of groundwater.[2] In East Hawai‘i, for example, invasive plants have already decreased the amount of ground water recharge by an estimated 85 million gallons a day. Healthy forests also anchor the soil, preventing erosion and runoff.[3] Additionally, they capture and store carbon dioxide, reducing the amount of the climate change-causing greenhouse gas in the atmosphere.

Now is a critical time to take measures to ensure a sustainable freshwater supply, as climate change is already impacting Hawai‘i.  A downward trend in the amount of rainfall statewide over the last century has been documented, with an even steeper decline since 1980.[4]  Streamflow has decreased. Air temperature has increased significantly, especially at high elevations where many of the remaining native forests exist. The warming and drying trends mean that it is now more important than ever to make sure that when we do get rainfall, we are maximizing the amount of water reaching our aquifers.

Watershed protection has proven to be a cost-effective, efficient way to replenish ground water. And, investing in protecting watersheds is best when done early, before forests become degraded and require expensive and difficult restoration.

Bill status

To be successful, the bills must be reviewed by several legislative committees that will hear testimony and make recommendations to the legislature. If a bill makes it through all of its assigned committees and three votes on the floor of the chamber (House or Senate) in which it was introduced, it “crosses over.” It must then make its way through the other chamber before it goes for a final vote or to conference committees where differences between the House and Senate can be hashed out.  In the case of these two pieces of legislation, members of the legislature have introduced companion bills, allowing the measures to be reviewed in both chambers simultaneously, in hopes of promoting their survival and timely passage. At any point, a committee could defer the bill, neglect to schedule a hearing, or recommend non-passage. Public attention and testimony may strongly affect a measure’s chances of survival.

The “bag bill,” Senate Bill 1165, was assigned to Senate Committees on Water and Land; Energy and Environment; and Ways and Means. Its companion, House Bill 934, has been assigned to House Committees on Energy and Environmental Protection; Consumer Protection and Commerce; and Finance. At this time, no hearings have been scheduled.

House Bill 935, relating to the conveyance tax, was assigned to House Committees on Water and Land; Housing; and Finance. The Committee on Water and Land reviewed the bill and heard testimony on January 28, and ultimately recommended passage with amendments. The bill goes next to the Committee on Housing, where it will be heard today, February 11, at 10:00 a.m. in Conference Room 329. The Senate Committees on Water and Land and Energy and Environment have scheduled a hearing for the companion bill, Senate Bill 1166, on Tuesday, February 12, at 1:15 pm in Conference Room 225.

For updates on the status of these measures, see capitol.hawaii.gov.

“Can you weather a white paper on climate change?”  Beth-Ann Kozlovich, host of Hawaii Public Radio’s weekday morning talk show The Conversation, asked this question by means of an introduction for Wednesday morning’s guest.  Ms. Kozlovich spoke with ICAP’s Senior Attorney, Richard Wallsgrove, about the recent ICAP white paper that he co-authored, titled, Water Resources and Climate Change Adaptation in Hawai‘i:  Adaptive Tools in the Current Law and Policy Framework.

Market-based adaptive tools and conservation measures recommended in the white paper were main topics of the conversation.  Mr. Wallsgrove explained, “In the state right now, we use more than 300 million gallons per day.  If we put that into milk jugs and laid them end to end, they would wrap around the earth twice every day.”  This level of current water use, paired with observed climate trends such as decreasing rainfall, rising temperatures, and rising sea-levels, led him to conclude that Hawai‘i’s water future is “very scary.”

Mr. Wallsgrove explained that cost-effective measures, such as a rebate system for water-conserving retrofits and online water use reporting, could have cost saving benefits now and allow for a more secure water future.

You can listen to the show in The Conversation’s archive.  The interview with Mr. Wallsgrove begins at 35:30.  The show airs weekday mornings from 8:00 – 9:00 a.m. local time on KIPO FM89.3 and KIPM FM89.7.

In August 2012, the Hawaiʻi Supreme Court ruled to vacate a 2010 decision made by the state Commission on Water Resource Management that impacts stream flows in Nā Wai ʻEhā, or the four great waters of Maui.

Two Maui community groups and the state Office of Hawaiian Affairs appealed the June 2010 water commission decision that amended instream flow standards for the Waiheʻe River and the Waiehu, ʻĪao, and Waikapū streams on Maui.  Currently, much of the water that once flowed in Nā Wai ʻEhā is being diverted for commercial use.  Commissioner Lawrence Miike dissented the 2010 decision, and had recommended restoring around half of the approximately 70 million gallons a day (mgd) diverted.  The commission decision had restored only 12.5 mgd, setting a standard that left two of the streams completely dry.

The state supreme court justices concluded that the water commission had failed to properly consider traditional and customary Native Hawaiian practices and the public’s rights to flowing streams.  Further, the court ruled that the commission needed to more thoroughly investigate and consider possible alternative water sources, such as non-potable wells and recycled wastewater. The court remanded the case back to the commission for a new decision that is consistent with the court’s ruling.

“When I look at ʻĪao and Waikapū Streams, they’re bone-dry, nothing but skeletal remains,” Rose Marie Hoʻoululāhui Lindsey Duey of Hui o Nā Wai ʻEhā told Earth Justice. “The supreme court’s decision restores my hope that the law stands for something, and that each of Nā Wai ʻEhā’s four streams will flow like justice from mauka (mountain) to makai (ocean).”

Hawaiian farmers in Nā Wai ʻEhā have long sought to end diversions and restore stream water, which supports traditional taro farming, native freshwater species, and near-shore fisheries, among other traditional practices and resources.  This conflict over diversion of the Nā Wai ʻEhā  began decades ago, and the ruling is considered a major victory for taro-farming communities on Maui.  Like the landmark Waiāhole decision in 2000, the court’s August 2012 ruling affirms the commission’s duty to enforce legal mandates of the public trust and has significant implications for future water commission decisions.

Photos: The ʻĪao stream flowing above diversion point (top) and the dry stream bed below the diversions. Source: Earthjustice 2012