The Consequences of Groundwater Withdrawals and their Implications for Sustainable Yield in Hawaiʻi
Dr. Scot Izuka | April 28, 2023
How much groundwater is available for human use from Hawai‘i’s aquifers? It depends. All groundwater withdrawals—even from the smallest wells—have consequences such as water-table decline, saltwater intrusion, and reduction of groundwater discharge to springs, streams, and the ocean. The larger the withdrawal, the larger the severity of the consequences. Terms like “safe” or “sustainable” yield are commonly misinterpreted to mean that some amount of water can be taken without consequences—but there’s no free lunch. The amount of groundwater available for human use depends on the severity of the consequences that a community is willing to accept. On one hand, a community’s resource managers need to decide on acceptable limits for the consequences; on the other hand, science needs to quantify the severity of the consequences for a given set of circumstances. Iterative communication between science and resource managers can work toward a balance between the need for groundwater withdrawals with the need to limit consequences. This presentation will discuss example studies in which analysis of existing data, collection and analysis of additional data, and numerical modeling are used to quantify the consequences of groundwater withdrawals in Hawai‘i.
Environmental Justice Through the Lens of Coastal Health
Dr. Eileen Nalley | April 14, 2023
A legacy of contamination from unsustainable land use affects the health of coastal ecosystems and communities around the globe. In Hawaiʻi and the Pacific Islands, where many communities are reliant on marine resources for their nutrition, livelihood, and cultural practices, contamination poses an acute risk to marine ecosystems and seafood consumers. Using a combination of tools ranging from meta-analysis to toxicology to interviews, we worked in close partnership with resource stewards, community nonprofits, and government agencies to assess the risks posed to the health of marine organisms and consumers and to contextualize these findings throughout the Pacific region. The focus of this work has primarily been on contaminant concentrations in commonly consumed fishes, trophic transfer of contaminants through coastal ecosystems, examining historic land use to assess risk in vulnerable communities, and contextualizing other health threats (e.g., ciguatera poisoning) within the framework of unsustainable land use and resulting habitat degradation. Though most of this work has been based in Hawaiʻi and the Marshall Islands, our findings are relevant for communities throughout the Pacific.
Envisioning Water Security and Resilience in the Pacific: Lessons from Integrated Ridge to Reef Studies in American Samoa
Ms. Mia Comeros and Dr. Chris Shuler | March 24, 2023
Enhancing actionable science links to management of natural resources in island communities is critically important given the strong land-sea connection, intrinsic vulnerability to terrestrial runoff and climate change impacts, and high dependencies on highly valued natural capital in nearshore coastal environments. Thus, science that translates and is operationalized into policy to protect watershed and reef ecosystems is needed to address challenges of economic, water, and food insecurity. On-top of this, Hawaiʻi and the U.S. Affiliated Pacific Islands have heightened vulnerability to interacting local and global stressors because of historical and current chemical contamination from Department of Defense activities. Addressing these challenges requires enhanced understanding of land-sea-people linkages and the processes underpinning nearshore coral reef ecosystem function and services. Here we draw on lessons from multiple ridge to reef studies in American Samoa in the last 10 years and highlight the highly collaborative nature of research, partnership-building, and knowledge sharing. We discuss the complexities of capturing the multiple and interacting drivers affecting coral reef function and services at the island-scale, important hydrologic information needed to support program planning, implementation, and evaluation at appropriate local context, and some of the challenges to effective multi-level water resource management decision-making. We suggest ways of increasing water science partnerships between American Samoa and Hawaiʻi to address the broader challenges of water security preparedness and resilience in the Pacific.
An Engineering Solution to Restoring Wai: Kānewai Spring and Kalauha‘iha‘i Fishpond
Mr. Chris Cramer and Ms. Hina Ioane | March 10, 2023
The 1990s widening of Kalanianaʻole Highway caused an environmental catastrophe by cutting the freshwater flow to Kalauhaʻihaʻi Fishpond in Niu, Oʻahu and Maunalua Bay. Nearby Kānewai Spring in Kuliʻouʻou was also severely damaged. In 2007, Maunalua Fishpond Heritage Center (MFHC) began working to return freshwater flow through these springs to the nearshore. Life-giving pūnāwai (water springs) were once plentiful and celebrated in Hawaiian moʻolelo. Today most are destroyed. Finding a lack of documentation, MFHC conducted oral histories to map the artesian water system.
Kānewai Spring is currently imperiled by a development project at its artesian source. However, water quality data gathered by Chaminade University students found it still able to support a range of native species. These same students found hypoxic conditions at the Kalauhaʻihaʻi Fishpond. Unfortunately, their findings indicate Kalauhaʻihaʻi can no longer host native fish and aquatic species.
Systemic failure to protect artesian water resources has allowed them to be destroyed. In 2023 to 2024, MFHC is collaborating with the State DLNR Engineering Branch which is scheduling repairs to the mauka to makai water flow through a trenchless drilling project. This innovative approach offers promise for many communities with ruined water resources.
Mālama Pu‘uloa: Fostering Innovative Collaboration to Restore Pearl Harbor to Abundance
Ms. Sandy Ward | February 24, 2023
It is clear that the watersheds of the ʻEwa district (moku) must be the focus of intense restoration and research efforts. Eight ʻEwa moku watersheds feed into Pearl Harbor (Puʻuloa) and include extensive shoreline wetlands, our island's primary drinking water aquifer, and thriving nearshore fisheries, all of which were historically abundant. While these waters continue to be impacted by pollution, neglect, and insufficient agency collaboration, there are reasons to be optimistic. This presentation will describe how a relatively new community non-profit is developing innovative approaches to restoration in the region. From a community perspective that includes concerns about food and water security, this presentation includes a call to the scientific community to focus their efforts on the challenges associated with the waters of Puʻuloa. Current and potential research collaborations play a vital role in positive, impactful, and community-driven change.
Puʻuloa Plankton Party: Student Focused Coastal Research
Dr. Donn Viviani | February 10, 2023
Puʻuloa (Pearl Harbor) is the largest estuary in the central Pacific. Puʻuloa is also understudied, particularly compared to other estuarine systems. Leeward Community College (Leeward CC) has a rich tradition of oceanographic investigation of Puʻuloa, dating back to the 1970s. Current Leeward CC students carry on this tradition, including time-series observations in Puʻuloa. Comparisons of coastal plankton across three sites (East Loch, West Loch, and the mouth of Puʻuloa) from 2019 through 2020 revealed higher taxonomic richness near the estuary mouth and lowest in West Loch. Near-weekly West Loch time-series observations in summer 2021 revealed plankton population changes compared to earlier observations. We then generated lists of planktonic organisms in Puʻuloa, from regularly abundant to occasionally present. These lists serve as a basis for further explorations of community structure, diversity, and ecology of plankton in this estuarine system. Leeward CC provides other undergraduate research experiences in partnership with colleagues from the Hawaiʻi Institute of Marine Biology, National Oceanic and Atmospheric Administration, UH Mānoa, and Sumida Farms. These partners provide the students with samples to analyze and field research opportunities that serve as a training platform as future scientists, while also letting them address real scientific questions.
Seedling Drought Tolerance in a Changing Climate
Dr. Kasey Barton | November 18, 2022
Climate change is altering water availability with dramatic consequences for plant performance and population stability. Seedlings are often more sensitive to water limitation than older plants of the same species due to their small size, relatively limited stored reserves, and acquisitive growth strategy. Because climate change is not only reducing total incoming precipitation, but also the timing, seedling recruitment is declining in many Hawaiian plants. Using experimental approaches in the field and greenhouse, combined with ecophysiological trait analysis, we have been investigating seedling drought tolerance across a diverse range of native and invasive Hawaiian plant species. Key findings include detection of climate mismatches constraining seedling germination and establishment in Hawaiʻi’s foundation tree, ʻōhiʻa lehua (Metrosideros polymorpha), confirmation that seedlings are sensitive to the timing as well as amount of water availability, significant variability across species in their potential tolerance to and longevity under extreme drought, and identification of interactive effects with herbivory. These studies indicate widespread and complex vulnerability of Hawaiʻi’s native plants to drought, highlighting seedling recruitment as a critically threatened process potentially leading to population instability and declines.
Potential Effects of Drought, Climate Change, and Cloud-Water Interception on Groundwater Recharge and Wildfire Risk in Hawai‘i
Dr. Alan Mair | November 4, 2022
Long-term downward trends of rainfall and concurrent long-term upward trends in drought duration and magnitude extend across most of the Hawaiian Islands. Some future climate projections indicate that rainfall is projected to further decrease across large areas of the state. Reduced rainfall can reduce groundwater recharge and reduce soil moisture, which can increase wildfire risk. Cloud-water interception can contribute substantially to total precipitation and help to lessen the negative effects of reduced rainfall on groundwater recharge and wildfire risk. Wildfire assessments in the continental United States have used estimates of soil moisture, evapotranspiration, and climatic water deficit as indicators of wildfire risk. In this study, water-budget models developed for the islands of Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi were used to quantify the effects of drought, future climate conditions, and the loss of cloud-water interception on groundwater recharge and wildfire risk. Island-wide summaries of groundwater recharge, soil moisture, evapotranspiration, and climatic water deficit for recent, drought, and future climate conditions quantify (1) hydrologic differences among conditions, (2) moderating effects of cloud-water interception, and (3) potential increases in wildfire risk.
Potential Effects of Drought, Climate Change, and Cloud-Water Interception on Groundwater Recharge and Wildfire Risk in Hawai‘i
Ms. Melissa Kunz | October 21, 2022
What is the state of drought knowledge and drought-related needs in Hawaiʻi? As part of the Pacific Drought Knowledge Exchange’s early needs-finding efforts, I conducted 24 interviews and a survey to learn about Hawaiʻi’s drought stakeholders’ information sources, knowledge, experiences, and needs. In this seminar I’ll present the results from the survey and interviews, share reflections on the needs-finding process and outputs, and explore how these learnings can feed back into building knowledge and connections among those interested in and impacted by drought.
Nutrient Removal and Resource Recovery from Municipal Wastewater
Dr. Zhiyue Wang | September 23, 2022
Wastewater is a promising source of clean water, energy, and nutrients. However, the reuse of municipal wastewater is a sustainability challenge that requires integrated approaches across scale. Such a challenge is further complicated by interconnected issues including climate change, water scarcity, and public health considerations. In this seminar, I will share some of my past experiences tackling engineering problems related to redesigning the nitrogen cycle, upgrading biological processes, and developing innovative engineering tools. Novel biotechnologies will be explored including microbial encapsulation and nitrous oxide recovery from wastewater. Molecular and mathematical tools are used to facilitate our understanding of biochemical processes, enhance treatment efficiencies, and expand a priori applications under both natural and engineered settings. With a multidisciplinary approach, future research could develop novel environmental biotechnologies for nutrient removal and resource recovery that can be integrated into the existing water infrastructure.
The Future of Storm Water Management on Oahu: Understanding Stormwater Impacts and Using Technology to Identify Solutions
Ms. Lauren Roth Venu and Mr. Randall Wakumoto | May 13, 2022
The City and County of Honolulu (CCH) Department of Facility Maintenance have been in the process of developing a stormwater utility (SWU) that will help CCH create a dedicated fund to invest in critical stormwater infrastructure operations, maintenance, and improvement projects. The proposed fee associated with the SWU will also provide incentives to property owners to reduce their stormwater runoff impacts. The presenters will share information regarding the SWU and the work to date with stakeholders, as well as introduce an innovative mobile app and data platform coined “Follow the Drop” that is being tested as a community engagement tool to support green stormwater infrastructure retrofits and the future SWU credit program.
May 13, 2022 Transcript (download here)
The Impacts of the Red Hill Crisis on the Board of Water Supply
Mr. G.D. Beckett and Dr. Iris van der Zander | May 6, 2022
The migration of fuel after a release is a complex process, controlled by geology, fluid characteristics, and other factors. The multiphase mechanics of fuel migration is more complex than groundwater flow, and Hawaiian basaltic settings provide the potential for both rapid transport and attenuation and buffering after the spill has stopped migrating. Of these factors, geologic complexity plays a strong role, particularly for fast-track pathways. The observational evidence of the November 2021 Red Hill fuel release indicates it reached the water production shaft in a matter of days, which is consistent with the broader Hawaiian experience and multiphase mechanics. This presentation will focus on the geologic and related factors controlling fuel transport at Hawaiian volcanic sites, such as Red Hill, and some observations of the resulting complexity. The presentation will also discuss fuel transformation products as both indicators of weathering, but also the implications those transformations may suggest for transport and risk.
May 6, 2022 Transcript (download here)
The Impacts of the Red Hill Crisis on the Board of Water Supply
Mr. Ernest Lau and Mr. Erwin Kawata | April 22, 2022
Mr. Ernest Lau, Manager and Chief Engineer of the Honolulu Board of Water Supply (BWS), will discuss how BWS has been impacted by the contamination crisis at the Red Hill Bulk Fuel Facility and what the agency is doing to address these impacts. At the end of the presentation, there will be an opportunity for questions from registered participants.
April 22, 2022 Transcript (download here)
Natural Source Zone Depletion of Petroleum Hydrocarbons at the Water Table
Dr. Barbara Bekins | April 8, 2022
To develop an appropriate mitigation strategy for groundwater contamination from long-term petroleum hydrocarbon spill sites, it is critical to understand how the mass and composition of the source changes over time. This presentation will focus on the research conducted at the site of a 1979 oil spill in northern Minnesota. To estimate the total mass lost, oil samples were collected in 2019 and 2020 and were analyzed for conservative biomarker concentrations, and then compared to a spilled oil reference sample. After 40 years, an estimated 50% of the total oil mass had been lost with values ranging from 22% to 57%, depending on the location. The analyses of the volatile concentration data showed that the losses of oil compounds were controlled by the compound’s susceptibility to degradation under methanogenic conditions and solubility. To study what happened to the compounds lost from the oil, the following were used: (1) carbon dioxide efflux, (2) groundwater concentration data, and (3) modeling. An estimated 86% of the carbon lost, exited the surface as carbon dioxide. The dissolved organic carbon (DOC) migrated to the saturated zone as hydrocarbons (22%), and partially transformed hydrocarbon products (78%). The concentrations of DOC decreased exponentially within 150 m from the source of contamination, indicating further biodegradation. The results on the nature and biological effects of the partial transformation products will be presented.
April 8, 2022 Transcript (download here)
HOW CLEAN IS CLEAN ENOUGH? Methods to Assess Environmental Risks Posed by Releases of Petroleum
Dr. Robert Brewer | April 1, 2022
Petroleum constitutes perhaps the most common type of environmental contamination on a global scale. From small gas stations to tank farms, pipelines and large oil fields, the assessment of the risk to human health and the environment is challenging due to the complex composition of petroleum products. This presentation reviews the fate of petroleum when released to the environment and the chemistry and toxicity of petroleum-related contaminants in the air, water, and soil. The risk assessment is defined in terms of three distinct groups of compounds: (1) individually targeted and well-studied compounds such as benzene, toluene, ethylbenzene, xylenes, and naphthalene (BTEXN); (2) non-specific aliphatic and aromatic hydrocarbons collectively referred to as “Total Petroleum Hydrocarbon (TPH)”; and (3) degradation compounds related to BTEXN and TPH mixtures, collectively referred to as “Hydrocarbon Oxidation Products (HOPs).” Risk is most often driven by TPH and/or HOPs compounds due to their overwhelming dominance in the contaminated media. This highlights the need to test for and consider these compounds as part of a human health and ecological risk assessment.
April 1, 2022 Transcript (download here)
An extended version of this presentation--including Dr. Brewer's notes and additional thoughts--is available at the Hawai‘i Department of Health, HEER webinar webpage: https://health.hawaii.gov/heer/guidance/heer-webinars/
QUESTION & ANSWER SESSION
Groundwater Flow in the Moanalua/Red Hill/Halawa Region: Evaluating Rates, Directions, and Contamination Risks
Mr. Robert Whittier and Dr. Donald Thomas | March 30, 2022
Due to unforeseen circumstances, a separate question and answer session was scheduled for the March 18, 2022 video presentation. Mr. Whittier and Dr. Thomas provided a brief summary of their presentation, followed by an opportunity for participants to engage in discussion of their timely and relevant research.
Groundwater Flow in the Moanalua/Red Hill/Halawa Region: Evaluating Rates, Directions, and Contamination Risks
Mr. Robert Whittier and Dr. Donald Thomas | March 18, 2022
The Navy stores more than 100 million gallons of petroleum-based fuels in underground storage tanks located just 100 to 150 feet above an Oahu aquifer, a primary drinking water source. Originally built in the 1940s, the Red Hill Bulk Fuel Storage Facility consists of 18 massive storage tanks and poses a contamination risk not only to the aquifer but to three other important public drinking water sources located within 2 km. Fuel leaks have occurred periodically over the decades and the Red Hill facility presents a particular contamination risk because (1) the two highest drinking water production sources are Maui-type wells (skimming tunnels) that draw water from the top of the water table, and (2) the fuels stored at the facility are characterized as “Light Non-aqueous Phase Liquids” (LNAPL) that, once released, will accumulate and spread across the top of the basal aquifer. The degree of risk of contamination to the drinking water sources is also dependent on groundwater flow trajectories and velocities beneath the tanks and surrounding areas and needs to be studied further to provide a more accurate assessment. The results of ongoing investigations around the facility will be integrated into a conceptual site model that should provide a template for continuing evaluation of contaminant risk and groundwater flow state-wide.
Biodegradation of Petroleum Hydrocarbons Controls Their Fate and Transport in Subsurface Environments
Dr. Tao Yan | Febraury 18, 2022
Exploration and consumption of petroleum hydrocarbons have led to frequent oil spills and contamination of aquatic and terrestrial ecosystems. Although every spill can have catastrophic consequences to the local ecosystem, contamination of groundwater aquifers represents the most direct and long-lasting threat to human health. This presentation will provide an overview of the current scientific understanding of microbial capabilities in degrading petroleum hydrocarbons. The dominant factor determining the fate of petroleum hydrocarbons in subsurface environments is biodegradation. We will discuss how the subsurface environmental conditions pose peculiar challenges to the biodegradation kinetics of petroleum hydrocarbons and contribute to their persistence. Finally, we will explore how biodegradation could potentially alter the transport behaviors of petroleum hydrocarbons and their degradation products, which presents unknowns and uncertainties to groundwater quality and human health.
February 18, 2022 Transcript (download here)
Degradation of Per- and Polyfluoroalkyl Substances (PFAS): Structure-Reactivity Relationships and Treatment Strategies
Dr. Jinyong Liu | December 15, 2021
Per- and polyfluoroalkyl substances (PFAS) are widely used manufactured chemicals that have been in existence since the 1940s and can be found in our drinking water, food, homes, and workplaces. PFAS are commonly known as “forever chemicals” because they tend to break down very slowly, and can build up in humans, animals, and the environment through decades of exposure. To protect communities, research is focusing on the toxicity of PFAS on human health and the environment, and how to mitigate any harmful effects implementing a complete, rapid, and cost-effective solution to the degradation of PFAS pollutants. Currently, industrial practitioners consider most PFAS treatment methods too expensive.
To address these challenges, we identified the PFAS structure-reactivity relationships and improved the photochemical system and lowered the EE/O. The optimized system achieved >99.7% removal and >90% overall defluorination of concentrated PFAS mixtures in brine. In this presentation, we will show our results of (1) complete defluorination of legacy PFAS through the existing redox processes and that a simple design is feasible, and (2) a large number of PFAS are not “forever chemicals.”
The Subak Traditional Irrigation System as a UNESCO World Heritage Site: Governing Bali’s Changing Landscapes
Wiwik Dharmiasih | December 1, 2021
Subak is a traditional irrigation and water management system that has existed for over a thousand years in Bali as an autonomous locally rooted institution. This unique system controls water allocation and resources distribution of farming resources, and is most commonly associated with the expansive rice terraces featured on travel brochures for “The Island of the Gods.” In addition, subak represents Bali’s Tri Hita Karana, an islandwide philosophy rooted in maintaining balance and harmony between people, nature, and the spiritual realm. However, increasing demand for water and land in Bali due to the growing tourism industry has threatened the existence of the subak system. By the early 2000s, concerted efforts to protect the subak by the Indonesian national government and Bali province resulted in its nomination as a UNESCO World Heritage Site. Despite its designation in 2012, the subak system continues to face tourism and development pressures. In this presentation, I will describe local perspectives on protecting the subak within the World Heritage Site and the continued challenges to the community. I will focus on the changing institutions of cultural and state-based institutions, tensions between conservation and development, and the impacts on water.
Building a Network of Projects Mauka to Makai to Protect and Restore Maunalua Bay
Pam Weiant | November 3, 2021
Please join us and learn about Mālama Maunalua, an organization dedicated to “restoring the health of Maunalua Bay through habitat restoration, science and planning, and education and outreach.” Maunalua Bay, located in Hawai‘i Kai along O‘ahu’s southeast shore, is one of the largest bays in the main Hawaiian Islands. It is also one of the most heavily used and impacted bays. Maunalua Bay’s marine resources are important for many reasons, including culture, livelihood, and recreation, but are degraded because of overutilization and urban development. For the past 15 years, Mālama Maunalua has been working on various projects to help protect and restore this treasured body of water. By taking a true mauka-to-makai approach, and partnering with local experts and organization, a unique network of restoration projects are having a big impact on the bay. This presentation will share new project ideas to mitigate land-based runoff, and will invite new collaborators and partners to join us and enhance our work. For more information about Mālama Maunalua and what we do, please visit: www.malamamaunalua.org.
What Does Sustainable Yield Sustain? What (and Who) is Left Out?
October 20, 2021
Dr. Jonathan Scheuer | October 20, 2021
The Hawai‘i Water Code mandates groundwater management by the determination of Sustainable Yields (SY), a modification of the “safe yield” concept forwarded over a century ago. The Water Commission, trustees of the water resources trust, have not changed their basic approach to setting SY since it was adopted in the 1990 Water Resources Protection Plan. Nearly every aquifer’s SY in Hawai‘i is regulated assuming the area has a single unconfined basal aquifer, and the Robust Analytical Model (RAM) is applied. The Commission is to be commended for regulating groundwater withdrawal and not setting SY equal to recharge. However, the approach has often failed the design goal of preventing rising chlorides in wells, led to decades of litigation, and in many areas failed to protect Public Trust uses of water. Frequent debates across Hawai‘i over the “correct SY” for particular areas distract from the structural shortcomings of the current SY approach. Continued universal application of RAM-driven SY favors resource extraction over Public Trust interests, and climate change driven reductions in recharge will increase disputes. A new approach to fulfilling the Code’s mandates is needed—guided by community identification of what needs to be sustained, with an explicit consideration of justice and grounded in current science. Specific “correct SY” discussions will be reviewed to illustrate these points and suggest pathways forward.
Hydrological Predictions from Hillslopes to Continents
Dr. Martyn Clark | October 6, 2021
The goal of the Global Water Futures (GWF) project is to manage the water futures in Canada, and other regions that are facing climate changes such as global warming, with innovative water science and decision-making tools. The GWF Core Modelling Team is developing tools to simulate and predict hydrologic processes. Some of our contributions include (1) ensemble forcing data for large-domain hydrological models, (2) multi-scale hydrologic models, (3) continental-domain network routing models, (4) ensemble methods for data assimilation, and (5) process-based methods for model benchmarking and model evaluation. The majority of our model development work is focused on applications for streamflow forecasting, water security assessments, and improving the representation of hydrologic processes in Earth System models. This presentation summarizes some of our recent research advances and their potential application in Hawai‘i.
Building Capacity for Water Quality Research and Monitoring on Maui
Dr. Andrea Kealoha | May 7, 2021
In 2020, the University of Hawai‘i Maui College (UHMC) opened Maui’s first water quality lab. The UHMC Water Quality Lab has three main goals: (1) provide UHMC students with educational opportunities for field work and research related to water quality, (2) build capacity for water quality monitoring on Maui, and (3) conduct research that benefits Hawaiʻi’s coastal ecosystems. This seminar will primarily focus on our lab’s current research projects that investigate the impact of multiple stressors, such as eutrophication and acidification, on coral reef ecosystem health.
NOAA Water Information for Hawaii: Resources to Support Decision-Making
Dr. Karen Bareford and Ms. Brenna Sweetman | April 23, 2021
Water resources stakeholders need access to consistent, high space and time-resolution, integrated water analyses, predictions, and data to address critical unmet information and service gaps related to floods, droughts, water quality, water availability, and climate change. A variety of tools are available to help address these gaps including the National Water Model (NWM), the Digital Coast platform’s resources, and the Adapting Stormwater Management for Coastal Floods product. The NWM is a continental scale hydrologic model that forecasts key components of the water cycle. The Digital Coast offers a collection of data, tools, and trainings for the coastal management community to address coastal and marine issues. The Adapting Stormwater Management for Coastal Floods product is a self-guided learning resource created to help communities better understand and assess possible impacts on stormwater systems. This presentation will introduce these products and services that can help inform decision-making in Hawai‘i.
Mountain-to-Sea Ecological-Resource Management: Forested Watersheds, Coastal Aquifers, and Groundwater Dependent Ecosystems
Dr. Kimberly Burnett and Dr. Christopher Wada | April 9, 2021
Improving the understanding of connections spanning from mountain to sea and integrating those connections into decision models have been increasingly recognized as key to effective coastal resource management. This presentation examines the relative importance of linkages between a forested watershed, a coastal groundwater aquifer, and a nearshore marine groundwater-dependent ecosystem (GDE) using a dynamic groundwater optimization framework. Data from the Kīholo aquifer on Hawai‘i Island were used to numerically illustrate optimal joint management strategies. We find that for a plausible range of watershed management costs, protecting part of the recharge capture area is always optimal. Results also suggested that optimal watershed management and groundwater pumping were most sensitive to changes in water demand growth and parameters that described nearshore salinity.
The Ala Wai Watershed From Nutrients to Microbes
Ms. Jessica Bullington and Mr. Sean Mahaffey | 12 Mar 2021
The Ala Wai Watershed is an important hydrologic system in Honolulu, surrounded by a highly populated area. The area includes the Makiki, Mānoa, and Pālolo streams, which flow into the Ala Wai Canal—an artificial estuary connected to the nearshore waters of Waikīkī. The Strategic Monitoring and Resilience Training (SMART) Ala Wai program at the University of Hawai‘i at Mānoa was created to monitor the water quality throughout the watershed. This presentation summarizes major findings from two aspects of the SMART program: variability of nutrients in the streams and pathogenic bacteria in the canal.
For more information on SMART, please visit http://www.smart-alawai.manoa.hawaii.edu/
Equity and Waiwai—Water, Rights and Relationships in a Changing Climate
Ms. Laurien Nuss | March 5, 2021
By law, the Office of Climate Change, Sustainability and Resiliency of the City and County of Honolulu is required to coordinate actions and policies to advance procedural, distributional, structural, intergenerational, and cultural equity. This presentation will focus on how the Climate Resilience and Equity Program is expanding the access, agency, and advocacy for communities’ (e.g., indigenous communities, women, and immigrants) experiencing social inequities dealing with climate changes. Discussion is encouraged on leadership, participation, and representation of the City’s climate adaptation and mitigation efforts addressing the needs and experiences of the affected communities that threaten public health, employment, and economic stability.
Guam Restoration of Watersheds (GROW) Initiative
Dr. Austin J. Shelton | February 26, 2021
The Guam Restoration of Watersheds (GROW) Initiative aims to revive island landscapes and downstream coral reefs. GROW advances U.N. Sustainable Development Goal 14 (Life Below Water) and Goal 15 (Life on Land) in alignment with the Guam Green Growth Action Framework. Coordinated by the University of Guam Center for Island Sustainability and Sea Grant, GROW partners use an interdisciplinary approach to test and develop novel tools to restore degraded watersheds, coral reefs, and fisheries. This presentation features a toolkit of watershed restoration strategies, including sediment filter socks, seed balls, and unmanned aerial vehicles. Dr. Shelton also discusses student capacity building efforts in marine and environmental sciences through the NSF Guam EPSCoR and NSF INCLUDES projects.
Zooming Into the Kapo‘o Tidepools in the Pūpūkea Marine Life Conservation District: A Community Perspective on Water Quality Issues
Professor Denise Antolini and Mr. Marvin Heskett | February 12, 2021
This presentation will “zoom in” on current water quality issues threatening the Kapo‘o Tidepools at Sharks Cove on the North Shore of O‘ahu. The Pūpūkea Marine Life Conservation District (MLCD) Class AA waters provide ocean sport opportunities such as a popular snorkeling and swimming area. The shallow tide pools found in the MLCD are considered marine life nurseries, which are helping to maintain the population of the numerous species in the area. More specifically, water quality threats to human health and marine life will be addressed from the perspective of two community groups—Mālama Pūpūkea-Waimea and the Surfrider Foundation.
Sea-Level Rise and Inundation of Infrastructure Including Coastal Cesspools and Wastewater Systems
Dr. Shellie Habel and Dr. Trista McKenzie | January 29, 2021
Sea-level rise induced impacts in Hawai‘i are becoming increasingly problematic and observable as infrastructure degradation and failure occurs; this includes onsite sewage disposal systems. This presentation reviews the impacts that outdated and aging wastewater infrastructure will increasingly have on our coastlines and low-lying urban areas as sea level continues to rise. Evidence of such impacts includes groundwater modeling that considers sea-level rise induced lifting of the coastal water table, firsthand accounts of systems exposed by erosion and large storms, and field-based geochemical tracers (e.g., radon, pharmaceuticals) of groundwater discharge and its wastewater content. Overall, it will take a focused and driven effort to keep the deteriorating systems off our beaches and contaminants out of our coastal waters.
Recent Water-Resource Studies by the USGS Pacific Islands Water Science Center
Delwyn Oki, Kolja Rotzoll, Jackson Mitchell, Alan Mair, and Chui Ling Cheng | December 09, 2020
The U.S. Geological Survey, Pacific Islands Water Science Center (PIWSC) collects hydrologic data and conducts studies in Hawaiʻi and the U.S. Affiliated Pacific Islands to improve understanding of water resources for the benefit of the nation. The hydrologic data collected and the studies conducted by the PIWSC address information needs related to the quantity and quality of groundwater and surface-water resources. For this seminar, a series of short presentations will describe recently completed or ongoing efforts related to groundwater availability (Molokaʻi and Maui), groundwater status and trends (Saipan), potential effects of climate change on water resources (State of Hawaiʻi), and water-resource monitoring needs (State of Hawaiʻi).
Solute Dispersion in Groundwater
December 02, 2020 | Dr. Peter Kitanidis
At least 98% of the earth’s groundwater is fresh water—in other words, water that is not seawater or ice. Groundwater is a valuable but fragile resource that is constantly threatened with contamination. However, predicting contaminant concentration values in the subsurface remains a great challenge. We will discuss some of the difficulties and, in particular, the role of dispersion.
Dispersion—the spreading of solutes—is a pronounced and important solute-transport phenomenon. The textbook methodology for modeling and predicting dispersion has been criticized, which has lead to debates as to what is the right approach. This presentation will review the real and imagined strengths and limitations of some methods for modeling and predicting the dispersion of solutes in groundwater.
Compartmentalization of the Terrestrial Water Cycle
Speaker: Dr. Jeffrey McDonnell | November 18, 2020
The catchment annual water balance (i.e., input minus output equals change in storage) is the most important equation in hydrology. But recent studies using stable isotope tracers show a much more complex terrestrial water cycle than simple hydrometric observations suggest. At scales from global to microscopic, the water cycle appears highly compartmentalized and poorly mixed at timescales well beyond the annual measurements of input and output. This presentation summarizes recent work and attempts to describe how this stored inventory of old water links to streamflow and transpiration outputs.
Future Desalination for the Pacific Islands
Dr. Albert Kim | November 4, 2020
The 21st century is an era of natural resource depletion. In the science and engineering community, food, energy, and water (FEW) are enduring research topics as they are vital resources for human life. Moreover, the sustainable future of human beings are threatened by climate change, global temperature increase, and sea level rise. Among the three components of FEW, water is the most critical resource because it is an essential raw resource to the food and energy production.
In the ocean-surrounded tropical Pacific Islands, it is vital to store enough water resources for short-term purposes and to have decade- and century-long plans for a stable water supply. This presentation will discuss proven, state-of-the-art desalination technologies and the appropriate applications for Hawai‘i.
Measuring and Modeling Aerosol-Cloud-Precipitation Interactions in Complex Terrain: Lessons Learned from IPHEx
Dr. Ana Barros | October 28, 2020
The Intense Observing Period (IOP) Integrated Precipitation and Hydrology Experiment (IPHEx) field campaign took place from 01 May to 15 June 2014 in the southeastern US and centered on the Southern Appalachian Mountains (SAM). IPHEx was one of the ground validation campaigns after NASA’s Global Precipitation Mission (GPM) core satellite launch. Precipitation and aerosol measurements were collected and operated simultaneously at a supersite in the inner mountain region during the IPHEx IOP. Other supersite instrumentation included two radars (W- and X-band), a ceilometer, and a microwave radiometer. The University of North Dakota (UND) Citation Research Aircraft was flown to characterize aerosol and cloud microphysics’ vertical structure, including liquid water content, and hydrometeor-size distributions over the ground sites. This data set offers a great opportunity to perform modeling studies of warm-season cloud formation, leading to precipitation in complex terrain. I will first discuss the regional climatology of clouds and precipitation, including their role in modulating SAM’s hydrology and ecology. Second, we will investigate aerosol-cloud-precipitation interactions (ACPI) leveraging IPHEx IOP observations and two different models: (1) a cloud-parcel model to focus on aerosol-cloud interactions, and (2) a numerical weather prediction model—specifically weather research and forecasting (WRF)—to assess the impact of aerosol properties on precipitation over the SAM. Finally, we synthesize and examine our findings’ implications for the measurement and modeling of orographic precipitation processes generally
Modeling Vadose Zone Processes using HYDRUS and its Specialized Module
October 14, 2020
Dr. Jirka Šimůnek | October 14, 2020
Agriculture is one of the most important non-point pollution sources due to the use of chemicals in plant and animal production. Many mathematical numerical models evaluating water flow and the fate and transport of these chemicals in the subsurface were developed over the last three or four decades. These models are now readily available and widely used. This presentation will first briefly review recent versions of the HYDRUS models widely used to model water flow, chemical movement, and heat transport through variably-saturated soils. I will discuss various specialized HYDRUS modules intended to simulate processes not available in the standard HYDRUS versions, such as the transport of multiple interacting solutes, preferential flow, colloid-facilitated solute transport, cosmic ray fluxes, or transport of fumigants. These new modules include the DualPerm, C-Ride, HP1/2/3, Wetland, UnsatChem, Fumigant, Cosmic, Furrow, and Slope3. Finally, I will briefly review many recent applications of the Hydrus models, which include modeling of various irrigation practices, different contaminants, and different cropping systems.
The Work-4-Water Initiative: Promoting Workforce Development, Infrastructure Investment, 400 Cesspool Replacements and Water Protection in Hawai‘i’s Four Counties
Stuart Coleman and Michael Mezzacapo | September 30, 2020
To help Hawai‘i deal with the unprecedented COVID-19 and resulting hardships, the Work-4-Water Initiative aims to create a workforce of development projects, and in the process, reduce the amount of pollution from cesspools and support statewide resilient economic and community recovery plans. With more than 88,000 cesspools discharging nearly 53 million gallons of untreated sewage into the ground each day, Hawai‘i has been struggling for years to find solutions to its numerous wastewater issues. The Work-4-Water Initiative provides the state an immediate opportunity to jump-start the mandated replacement of cesspools, while simultaneously training and employing a specialized, non-tourism based workforce. Our plan will create shovel-ready projects across the state, stimulating the economy, and improving water quality and public health for residents and visitors alike through education, hands-on training, job creation, and pilot testing of more than 400 cesspool conversion sites on Hawai‘i, Maui, Kaua‘i, and O‘ahu.
Simulating Impacts of Land Cover Change and Climate Change on Groundwater Recharge in Maui
February 14, 2020
Dr. Laura Brewington | February 14, 2020
The objective of this study was to develop an integrated land cover/hydrological modeling framework using remote sensing and geographic information systems (GIS) data, stakeholder input, climate information and projections, and empirical data to estimate future groundwater recharge on the island of Maui, Hawaiʻi. Four future land-cover scenarios and two downscaled climate projections were used to estimate the end of the century mean annual groundwater recharge. The future scenarios focus were (1) conservation, (2) maintaining the status quo, (3) development, and (4) balancing conservation and development. The downscaled climate projections developed were (1) “dry future climate” and (2) “wet future climate.” To understand how the changing land management and climate could influence groundwater recharge, the results were compared to the estimated recharge using the 2017 baseline land cover. The estimated recharge increased island-wide under all future land-cover and climate combinations and was dominated by specific land cover transitions. To better describe the availability of groundwater across Maui, the water-budget modeling framework presented in this study provided information on the “supply” side, while the numerical groundwater modeling approach incorporated the “demand” side. Based on our findings, a spatially explicit scenario planning process and modeling framework would be able to communicate the possible consequences and tradeoff of land cover change under a changing climate, and can serve as a relevant tool for landscape-level management and decision making.
Working Together: Using Cloud-Based Collaborative Platforms to Facilitate Hydrologic Modeling and Data Analysis
Dr. Christopher Shuler | January 31, 2020
Recent advancements in social networking have influenced how we communicate professionally, how we work collaboratively, and how we approach data-science. Scientific endeavors—especially computational tasks such as groundwater modeling or exploratory data analysis—are poised to take advantage of these new developments. Improving the shareability of information has revolutionized how we work with each other, and revealed a new process-based paradigm that promotes enhanced collaboration and maintenance of long-standing project partnerships. In this presentation I’ll talk about my experiences using various cloud-based platforms such as GitHub and Google Colab to share data and work with researchers and stakeholders on hydrologic projects throughout Hawai‘i and American Samoa. These projects include the continuing development of a collaborative groundwater modeling framework with a water utility in American Samoa; using free google-based tools to manage a multi-disciplinary, statewide effort to understand the effects of non-point wastewater pollution on our coasts; and developing an open-access water budget model that is being used by multiple stakeholders to fill different needs.
Water Impacts of Invasive Plants in Hawai‘i
Speaker: Dr. Tom Giambelluca | November 5, 2019
Replacement of native plants by non-native invasive species can affect water processes and impact water resources in several ways. Perhaps the most important effect of invasion is the possible increase in transpiration by fast-growing invasive plants, leading to a greater proportion of water input being lost to the atmosphere as evapotranspiration. Invasive plants in Hawai‘i are widely believed to use more water (i.e., to have higher transpiration rates) than the native plants they replace. If true, this would mean that the widespread invasion of Hawai‘i’s ecosystems by non-native plants is having a big negative impact on our water resources by reducing streamflow and groundwater recharge. However, the research to demonstrate the effect of invasion on evapotranspiration is still relatively limited. In this presentation, I will discuss the reasons why invasive plants might be big water users and show the results of our field observations of transpiration and total evaporative water loss in native- and non-native-dominated ecosystems.
WATER ACCOUNTING FOR THE STATE OF HAWAI‘I: RESULTS FROM O‘AHU AND MAUI
Dr. Kirsten Oleson | October 22, 2019
In this project, we inventoried and assessed the stocks and flows of freshwater in Hawai‘i’s natural systems and human economy, following the integrated approach proposed by the United Nations’ System of Environmental-Economic Accounts for Water. In partnership with potential users of this information and providers of the data, as well as national and international experts, we developed reporting protocols and accounting tables for the Hawaiian Islands that are consistent with national level methods. They include (1) compiling integrated hydrological-economic water supply and use, and asset accounts; (2) identifying data gaps and next steps; and (3) raising awareness of accounting as a tool for sustainable management. The resulting island-scale water supply, use tables, and asset accounts detail stocks and flows between the environment and the economy for the two islands (O‘ahu and Maui). The products can serve as a clarifying guide to make fundamental choices about Hawai‘i’s various paths to economic development. The research can directly inform difficult choices about the water-energy-food nexus critical to Hawai‘i’s sustainability and security.
SUPPORTING CLIMATE CHANGE DECISION MAKING: DATA TRANSFORMATION AND KNOWLEDGE EXCHANGE WITH RESOURCE MANAGERS IN THE PACIFIC ISLANDS
Dr. Abby Frazier | October 8, 2019
Land managers are facing co-occurring threats to their landscapes such as climate change, invasive species, wildfire, and drought. As novel ecosystems and climates emerge—particularly hotter and drier climates—it is critical that scientists produce locally relevant, timely, and actionable science products. Trends in rainfall and characteristics of drought have been analyzed for the State of Hawai‘i since 1920, and additional high-resolution climate datasets have been recently produced (e.g., 25 years of gridded daily rainfall and temperature). However, the ability to use GIS is needed to extract site-specific information as no geospatial tools have been developed. For future climate projections, only raw climate model outputs are available for users. A knowledge exchange and technical assistance process is needed to encourage formal collaboration between researchers and managers. To address this need, we are piloting a knowledge exchange and technical assistance process with individual land managers in Hawai‘i and the U.S.-Affiliated Pacific Islands to co-produce customized site-specific drought and climate data products based on the needs of each manager. To improve the accessibility of the downscaled climate projections in Hawai‘i, the raw outputs have been re-processed and transformed into derived variables in raster format and standardized across models. This often-overlooked role of translating scientific outputs into usable, accessible data formats and engaging resource managers in research planning and knowledge co-production is essential to enable and support informed climate change decision making.
NATURAL AND CONTAMINANT CHEMISTRY OF FRESHWATER STREAMS, GROUNDWATER, AND WASTEWATER TREATMENT PLANT EFFLUENTS ON THE HAWAIIAN ISLANDS
Dr. Larry Barber | September 24, 2019
Sustainability of freshwater resources on island ecosystems relies on a detailed understanding of the sources and loading of contaminants and their impact on water quality. Considerable attention has been given to constituents such as nutrients and bacteria, but less is known about the occurrence and sources of unregulated contaminants such as trace elements and consumer product chemicals (pharmaceuticals and personal care products). Between 2014 and 2016 the U.S. Geological Survey conducted a survey of Hawaiian freshwaters on the islands of Kauai, Oahu, Maui, and Hawaii to assess the inorganic and organic chemistry of surface water and groundwater systems. This survey provides an important benchmark of the occurrence and sources for a variety of contaminants that are not typically investigated.
HYDROLOGICAL MODELING CHALLENGES IN HAWAII AND THE PACIFIC
Dr. Aly I. El-Kadi | September 13, 2019
Hydrological modeling in Hawaii and similar areas is challenging due to complicated hydrogeological features, steep topography, and variable climate conditions. This presentation will discuss the modeling efforts of the hydrology group over the past decades. Specifically covered include effects of climate change on Heeia watershed, American Samoa groundwater sustainability, surface water harvesting, and modeling of local scale geological variability. Progress of the current ‘Ike Wai modeling for West Hawaii’s groundwater will be also covered. Model developments are derived by the scale of the problem, data availability, and modeling objectives.
EVALUATING THE EFFECTS OF FUTURE CLIMATE AND LAND-COVER CONDITIONS ON GROUNDWATER RESOURCES FOR THE ISLAND OF MAUI, HAWAI‘I
Drs. Victoria Keener, Laura Brewington, and Alan Mair | April 23, 2019
Part I. Participatory Scenario Planning for Climate Change Adaptation: Projected Future Climate and Stakeholder-Defined Land-Cover Scenarios for the Island of Maui, Hawai‘i —Victoria Keener and Laura Brewington (East-West Center & NOAA Pacific Regional Integrated Sciences & Assessments)
Abstract: For the last century, the island of Maui has been the center of environmental, agricultural, and legal conflict with respect to both surface and groundwater allocation. Planning for sustainable future freshwater supply in Hawai‘i requires adaptive policies and decision-making that emphasizes private and public partnerships and knowledge transfer between scientists and non-scientists. To quantify future changes in an island-scale climate and groundwater recharge under different land uses, we will discuss downscaled dynamical and statistical future climate projects used in a participatory scenario building process. The participatory scenario planning began in 2012, bringing together a diverse group of ~100 decision-makers in government, watershed restoration, agriculture, and conservation to (1) determine the type of information they would find helpful in planning for climate change, and (2) develop a set of nested scenarios that represent alternative climate and management futures. This integration of knowledge is an iterative process, resulting in flexible and transparent narratives of complex futures comprised of information at multiple scales. We will present an overview of the downscaling, scenario building, and stakeholder response.
Part II. Groundwater Recharge for Projected Future Climate and Stakeholder-Defined Land-Cover Scenarios for the Island of Maui, Hawai‘i —Alan Mair (USGS Pacific Islands Water Science Center)
Abstract: Groundwater availability on Maui can be affected by changes in climate and land cover. To evaluate the availability of fresh groundwater under projected future climate and stakeholder-defined land-cover conditions, estimates of groundwater recharge are needed. As such, a water-budget model developed by the U.S. Geological Survey was used to estimate the spatial distribution of recharge for 11 unique combinations of climate and land-cover conditions. A variety of available research material was used in this study to represent the diversity of conditions, including two sets of end-of-century climate projects developed by University of Hawai‘i researchers, and future land-cover scenarios developed by Pacific RISA researchers. In one combination of climate and land-cover conditions, the results of the water budget for two future climate scenarios indicated a decrease across central and leeward areas of Maui, increases across windward areas of Haleakala, and opposing changes for the remaining parts of Maui. The projected changes in recharge for the future land-cover scenarios do suggest that appropriate land management may help to mitigate the effects of a drying climate.
CHARACTERIZING THE STREAM AND ITS ASSOCIATION WITH THE ECOSYSTEM IN HAWAI‘I
Dr. Yin-Phan Tsang | April 16, 2019
This presentation will consist of two parts, based on recent studies focusing on Hawaiian streams and ecosystems.
Part I. Characterizing Natural Barriers to Non-native Stream Fauna in Hawai‘i—Waterfalls are natural barriers that influence the distribution and dispersion of aquatic species. In Hawai‘i, it is assumed that non-native species are unable to pass waterfall barriers, yet they are still present above some waterfalls, possibly facilitated by human introduction. In this study, we used a landscape approach to identify likely human introductions and examined the ability of 14 non-native stream fauna to bypass waterfalls when the possibility of human introduction is eliminated. This study highlights the role that people play in facilitating species introductions in otherwise inaccessible habitats.
Part II. Temporal Shifts in the Magnitude of Peak Streamflow and Its Associated Rainfall Across the Hawaiian Islands—Previous studies show that extreme rainfall events are becoming more common. However, there is little research available that examines the temporal and spatial trends of peak streamflow (peak flow) events associated with heavy rainfall events. We analyzed the annual peak flow and the annual maximum rainfall trends of 112 stream crest gages from the U.S. Geological Survey, and an additional 82 rain gages from the National Centers for Environmental Information, across the Hawaiian Islands from the water years 1970 to 2005. To add to the current knowledge of flood risk and management in Hawai‘i, our study discussed how the annual peak flows changed over time, patterns in their spatial distribution, and how they are associated with rainfall.
*Please note, due to technical circumstances, the audio was unable to be captured during the video presentation below. We apologize for any inconvenience.*
CHALLENGES IN EVALUATING MICROBIAL BEACH WATER QUALITY IN HAWAI‘I
Dr. Marek Kirs | April 2, 2019
Abstract: In an effort to improve current water quality monitoring programs, the Water Resources Research Center has been engaged in multiple research projects pertaining to microbial water quality indicators, specifically in a tropical environment. This presentation will summarize the results of selected projects from 2013 to 2019. The projects addresses two major issues hampering the application of the EPA recommended Recreational Water Quality Criteria in Hawai‘i: (1) the growth of the current microbial water quality indicators in extra-enteric environments (i.e., soils and vegetation), and (2) the lack of information on contamination sources when the microbial water quality indicators are detected. My presentation will focus on the following, as it applies to Hawai‘i: (1) our current efforts to determine the health risk associated with current and alternative microbial water quality indicator levels, (2) the evaluation and application of molecular microbial source tracking (MST) methods, (3) the evaluation and application of rapid EPA method 1609 and 1611 for beach notification purposes, (4) utilization of a portable multi-use automated concentration system (PMACS) for the MST in our coastal environments, and (5) the hidden bacterial diversity in our groundwater.
ESTIMATION OF EVAPOTRANSPIRATION AND GROSS PRIMARY PRODUCTIVITY VIA VARIATIONAL ASSIMILATION OF REMOTELY SENSED LAND SURFACE TEMPERATURE AND LEAF AREA INDEX
Dr. Sayed Bateni | January 22, 2019
To estimate evapotranspiration and gross primary productivity, land surface temperature (LST) and leaf area index (LAI) measurements were assimilated into a coupled surface energy balance-vegetation dynamic model (SEB-VDM) within a variational data assimilation (VDA) system. The SEB and VDM are coupled by relating photosynthesis in the VDM to transpiration in the SEB equation. The unknown parameters of the VDA system are (1) bulk heat transfer coefficient (CHN), (2) soil evaporative fraction (EFs), (3) canopy evaporative fraction (EFc), and (4) specific leaf area (cg). The performance of the VDA approach was tested in the Heihe River Basin (HRB) extensively, which is located in northwest China. The results show that the developed VDA framework performs well in different environmental conditions, and the estimated evapotranspiration and gross primary productivity agree well with the corresponding measurements from the eddy covariance stations.
Groundwater Flow in the Moanalua/Red Hill/Halawa Region: Evaluating Rates, Directions, and Contamination Risks
Mr. Robert Whittier and Dr. Donald Thomas | March 18, 2022
The Navy stores more than 100 million gallons of petroleum-based fuels in underground storage tanks located just 100 to 150 feet above an Oahu aquifer, a primary drinking water source. Originally built in the 1940s, the Red Hill Bulk Fuel Storage Facility consists of 18 massive storage tanks and poses a contamination risk not only to the aquifer but to three other important public drinking water sources located within 2 km. Fuel leaks have occurred periodically over the decades and the Red Hill facility presents a particular contamination risk because (1) the two highest drinking water production sources are Maui-type wells (skimming tunnels) that draw water from the top of the water table, and (2) the fuels stored at the facility are characterized as “Light Non-aqueous Phase Liquids” (LNAPL) that, once released, will accumulate and spread across the top of the basal aquifer. The degree of risk of contamination to the drinking water sources is also dependent on groundwater flow trajectories and velocities beneath the tanks and surrounding areas and needs to be studied further to provide a more accurate assessment. The results of ongoing investigations around the facility will be integrated into a conceptual site model that should provide a template for continuing evaluation of contaminant risk and groundwater flow state-wide.
Degradation of Per- and Polyfluoroalkyl Substances (PFAS): Structure-Reactivity Relationships and Treatment Strategies
Dr. Jinyong Liu | December 15, 2021
Per- and polyfluoroalkyl substances (PFAS) are widely used manufactured chemicals that have been in existence since the 1940s and can be found in our drinking water, food, homes, and workplaces. PFAS are commonly known as “forever chemicals” because they tend to break down very slowly, and can build up in humans, animals, and the environment through decades of exposure. To protect communities, research is focusing on the toxicity of PFAS on human health and the environment, and how to mitigate any harmful effects implementing a complete, rapid, and cost-effective solution to the degradation of PFAS pollutants. Currently, industrial practitioners consider most PFAS treatment methods too expensive.
To address these challenges, we identified the PFAS structure-reactivity relationships and improved the photochemical system and lowered the EE/O. The optimized system achieved >99.7% removal and >90% overall defluorination of concentrated PFAS mixtures in brine. In this presentation, we will show our results of (1) complete defluorination of legacy PFAS through the existing redox processes and that a simple design is feasible, and (2) a large number of PFAS are not “forever chemicals.”
The Subak Traditional Irrigation System as a UNESCO World Heritage Site: Governing Bali’s Changing Landscapes
Wiwik Dharmiasih | December 1, 2021
Subak is a traditional irrigation and water management system that has existed for over a thousand years in Bali as an autonomous locally rooted institution. This unique system controls water allocation and resources distribution of farming resources, and is most commonly associated with the expansive rice terraces featured on travel brochures for “The Island of the Gods.” In addition, subak represents Bali’s Tri Hita Karana, an islandwide philosophy rooted in maintaining balance and harmony between people, nature, and the spiritual realm. However, increasing demand for water and land in Bali due to the growing tourism industry has threatened the existence of the subak system. By the early 2000s, concerted efforts to protect the subak by the Indonesian national government and Bali province resulted in its nomination as a UNESCO World Heritage Site. Despite its designation in 2012, the subak system continues to face tourism and development pressures. In this presentation, I will describe local perspectives on protecting the subak within the World Heritage Site and the continued challenges to the community. I will focus on the changing institutions of cultural and state-based institutions, tensions between conservation and development, and the impacts on water.
Building a Network of Projects Mauka to Makai to Protect and Restore Maunalua Bay
Pam Weiant | November 3, 2021
Please join us and learn about Mālama Maunalua, an organization dedicated to “restoring the health of Maunalua Bay through habitat restoration, science and planning, and education and outreach.” Maunalua Bay, located in Hawai‘i Kai along O‘ahu’s southeast shore, is one of the largest bays in the main Hawaiian Islands. It is also one of the most heavily used and impacted bays. Maunalua Bay’s marine resources are important for many reasons, including culture, livelihood, and recreation, but are degraded because of overutilization and urban development. For the past 15 years, Mālama Maunalua has been working on various projects to help protect and restore this treasured body of water. By taking a true mauka-to-makai approach, and partnering with local experts and organization, a unique network of restoration projects are having a big impact on the bay. This presentation will share new project ideas to mitigate land-based runoff, and will invite new collaborators and partners to join us and enhance our work. For more information about Mālama Maunalua and what we do, please visit: www.malamamaunalua.org.
What Does Sustainable Yield Sustain? What (and Who) is Left Out?
October 20, 2021
Dr. Jonathan Scheuer | October 20, 2021
The Hawai‘i Water Code mandates groundwater management by the determination of Sustainable Yields (SY), a modification of the “safe yield” concept forwarded over a century ago. The Water Commission, trustees of the water resources trust, have not changed their basic approach to setting SY since it was adopted in the 1990 Water Resources Protection Plan. Nearly every aquifer’s SY in Hawai‘i is regulated assuming the area has a single unconfined basal aquifer, and the Robust Analytical Model (RAM) is applied. The Commission is to be commended for regulating groundwater withdrawal and not setting SY equal to recharge. However, the approach has often failed the design goal of preventing rising chlorides in wells, led to decades of litigation, and in many areas failed to protect Public Trust uses of water. Frequent debates across Hawai‘i over the “correct SY” for particular areas distract from the structural shortcomings of the current SY approach. Continued universal application of RAM-driven SY favors resource extraction over Public Trust interests, and climate change driven reductions in recharge will increase disputes. A new approach to fulfilling the Code’s mandates is needed—guided by community identification of what needs to be sustained, with an explicit consideration of justice and grounded in current science. Specific “correct SY” discussions will be reviewed to illustrate these points and suggest pathways forward.
Hydrological Predictions from Hillslopes to Continents
Dr. Martyn Clark | October 6, 2021
The goal of the Global Water Futures (GWF) project is to manage the water futures in Canada, and other regions that are facing climate changes such as global warming, with innovative water science and decision-making tools. The GWF Core Modelling Team is developing tools to simulate and predict hydrologic processes. Some of our contributions include (1) ensemble forcing data for large-domain hydrological models, (2) multi-scale hydrologic models, (3) continental-domain network routing models, (4) ensemble methods for data assimilation, and (5) process-based methods for model benchmarking and model evaluation. The majority of our model development work is focused on applications for streamflow forecasting, water security assessments, and improving the representation of hydrologic processes in Earth System models. This presentation summarizes some of our recent research advances and their potential application in Hawai‘i.
Building Capacity for Water Quality Research and Monitoring on Maui
Dr. Andrea Kealoha | May 7, 2021
In 2020, the University of Hawai‘i Maui College (UHMC) opened Maui’s first water quality lab. The UHMC Water Quality Lab has three main goals: (1) provide UHMC students with educational opportunities for field work and research related to water quality, (2) build capacity for water quality monitoring on Maui, and (3) conduct research that benefits Hawaiʻi’s coastal ecosystems. This seminar will primarily focus on our lab’s current research projects that investigate the impact of multiple stressors, such as eutrophication and acidification, on coral reef ecosystem health.
NOAA Water Information for Hawaii: Resources to Support Decision-Making
Dr. Karen Bareford and Ms. Brenna Sweetman | April 23, 2021
Water resources stakeholders need access to consistent, high space and time-resolution, integrated water analyses, predictions, and data to address critical unmet information and service gaps related to floods, droughts, water quality, water availability, and climate change. A variety of tools are available to help address these gaps including the National Water Model (NWM), the Digital Coast platform’s resources, and the Adapting Stormwater Management for Coastal Floods product. The NWM is a continental scale hydrologic model that forecasts key components of the water cycle. The Digital Coast offers a collection of data, tools, and trainings for the coastal management community to address coastal and marine issues. The Adapting Stormwater Management for Coastal Floods product is a self-guided learning resource created to help communities better understand and assess possible impacts on stormwater systems. This presentation will introduce these products and services that can help inform decision-making in Hawai‘i.
Mountain-to-Sea Ecological-Resource Management: Forested Watersheds, Coastal Aquifers, and Groundwater Dependent Ecosystems
Dr. Kimberly Burnett and Dr. Christopher Wada | April 9, 2021
Improving the understanding of connections spanning from mountain to sea and integrating those connections into decision models have been increasingly recognized as key to effective coastal resource management. This presentation examines the relative importance of linkages between a forested watershed, a coastal groundwater aquifer, and a nearshore marine groundwater-dependent ecosystem (GDE) using a dynamic groundwater optimization framework. Data from the Kīholo aquifer on Hawai‘i Island were used to numerically illustrate optimal joint management strategies. We find that for a plausible range of watershed management costs, protecting part of the recharge capture area is always optimal. Results also suggested that optimal watershed management and groundwater pumping were most sensitive to changes in water demand growth and parameters that described nearshore salinity.
The Ala Wai Watershed From Nutrients to Microbes
Ms. Jessica Bullington and Mr. Sean Mahaffey | 12 Mar 2021
The Ala Wai Watershed is an important hydrologic system in Honolulu, surrounded by a highly populated area. The area includes the Makiki, Mānoa, and Pālolo streams, which flow into the Ala Wai Canal—an artificial estuary connected to the nearshore waters of Waikīkī. The Strategic Monitoring and Resilience Training (SMART) Ala Wai program at the University of Hawai‘i at Mānoa was created to monitor the water quality throughout the watershed. This presentation summarizes major findings from two aspects of the SMART program: variability of nutrients in the streams and pathogenic bacteria in the canal.
For more information on SMART, please visit http://www.smart-alawai.manoa.hawaii.edu/
Equity and Waiwai—Water, Rights and Relationships in a Changing Climate
Ms. Laurien Nuss | March 5, 2021
By law, the Office of Climate Change, Sustainability and Resiliency of the City and County of Honolulu is required to coordinate actions and policies to advance procedural, distributional, structural, intergenerational, and cultural equity. This presentation will focus on how the Climate Resilience and Equity Program is expanding the access, agency, and advocacy for communities’ (e.g., indigenous communities, women, and immigrants) experiencing social inequities dealing with climate changes. Discussion is encouraged on leadership, participation, and representation of the City’s climate adaptation and mitigation efforts addressing the needs and experiences of the affected communities that threaten public health, employment, and economic stability.
Guam Restoration of Watersheds (GROW) Initiative
Dr. Austin J. Shelton | February 26, 2021
The Guam Restoration of Watersheds (GROW) Initiative aims to revive island landscapes and downstream coral reefs. GROW advances U.N. Sustainable Development Goal 14 (Life Below Water) and Goal 15 (Life on Land) in alignment with the Guam Green Growth Action Framework. Coordinated by the University of Guam Center for Island Sustainability and Sea Grant, GROW partners use an interdisciplinary approach to test and develop novel tools to restore degraded watersheds, coral reefs, and fisheries. This presentation features a toolkit of watershed restoration strategies, including sediment filter socks, seed balls, and unmanned aerial vehicles. Dr. Shelton also discusses student capacity building efforts in marine and environmental sciences through the NSF Guam EPSCoR and NSF INCLUDES projects.
Zooming Into the Kapo‘o Tidepools in the Pūpūkea Marine Life Conservation District: A Community Perspective on Water Quality Issues
Professor Denise Antolini and Mr. Marvin Heskett | February 12, 2021
This presentation will “zoom in” on current water quality issues threatening the Kapo‘o Tidepools at Sharks Cove on the North Shore of O‘ahu. The Pūpūkea Marine Life Conservation District (MLCD) Class AA waters provide ocean sport opportunities such as a popular snorkeling and swimming area. The shallow tide pools found in the MLCD are considered marine life nurseries, which are helping to maintain the population of the numerous species in the area. More specifically, water quality threats to human health and marine life will be addressed from the perspective of two community groups—Mālama Pūpūkea-Waimea and the Surfrider Foundation.
Sea-Level Rise and Inundation of Infrastructure Including Coastal Cesspools and Wastewater Systems
Dr. Shellie Habel and Dr. Trista McKenzie | January 29, 2021
Sea-level rise induced impacts in Hawai‘i are becoming increasingly problematic and observable as infrastructure degradation and failure occurs; this includes onsite sewage disposal systems. This presentation reviews the impacts that outdated and aging wastewater infrastructure will increasingly have on our coastlines and low-lying urban areas as sea level continues to rise. Evidence of such impacts includes groundwater modeling that considers sea-level rise induced lifting of the coastal water table, firsthand accounts of systems exposed by erosion and large storms, and field-based geochemical tracers (e.g., radon, pharmaceuticals) of groundwater discharge and its wastewater content. Overall, it will take a focused and driven effort to keep the deteriorating systems off our beaches and contaminants out of our coastal waters.
Recent Water-Resource Studies by the USGS Pacific Islands Water Science Center
Delwyn Oki, Kolja Rotzoll, Jackson Mitchell, Alan Mair, and Chui Ling Cheng | December 09, 2020
The U.S. Geological Survey, Pacific Islands Water Science Center (PIWSC) collects hydrologic data and conducts studies in Hawaiʻi and the U.S. Affiliated Pacific Islands to improve understanding of water resources for the benefit of the nation. The hydrologic data collected and the studies conducted by the PIWSC address information needs related to the quantity and quality of groundwater and surface-water resources. For this seminar, a series of short presentations will describe recently completed or ongoing efforts related to groundwater availability (Molokaʻi and Maui), groundwater status and trends (Saipan), potential effects of climate change on water resources (State of Hawaiʻi), and water-resource monitoring needs (State of Hawaiʻi).
Solute Dispersion in Groundwater
December 02, 2020 | Dr. Peter Kitanidis
At least 98% of the earth’s groundwater is fresh water—in other words, water that is not seawater or ice. Groundwater is a valuable but fragile resource that is constantly threatened with contamination. However, predicting contaminant concentration values in the subsurface remains a great challenge. We will discuss some of the difficulties and, in particular, the role of dispersion.
Dispersion—the spreading of solutes—is a pronounced and important solute-transport phenomenon. The textbook methodology for modeling and predicting dispersion has been criticized, which has lead to debates as to what is the right approach. This presentation will review the real and imagined strengths and limitations of some methods for modeling and predicting the dispersion of solutes in groundwater.
Compartmentalization of the Terrestrial Water Cycle
Speaker: Dr. Jeffrey McDonnell | November 18, 2020
The catchment annual water balance (i.e., input minus output equals change in storage) is the most important equation in hydrology. But recent studies using stable isotope tracers show a much more complex terrestrial water cycle than simple hydrometric observations suggest. At scales from global to microscopic, the water cycle appears highly compartmentalized and poorly mixed at timescales well beyond the annual measurements of input and output. This presentation summarizes recent work and attempts to describe how this stored inventory of old water links to streamflow and transpiration outputs.
Future Desalination for the Pacific Islands
Dr. Albert Kim | November 4, 2020
The 21st century is an era of natural resource depletion. In the science and engineering community, food, energy, and water (FEW) are enduring research topics as they are vital resources for human life. Moreover, the sustainable future of human beings are threatened by climate change, global temperature increase, and sea level rise. Among the three components of FEW, water is the most critical resource because it is an essential raw resource to the food and energy production.
In the ocean-surrounded tropical Pacific Islands, it is vital to store enough water resources for short-term purposes and to have decade- and century-long plans for a stable water supply. This presentation will discuss proven, state-of-the-art desalination technologies and the appropriate applications for Hawai‘i.
Measuring and Modeling Aerosol-Cloud-Precipitation Interactions in Complex Terrain: Lessons Learned from IPHEx
Dr. Ana Barros | October 28, 2020
The Intense Observing Period (IOP) Integrated Precipitation and Hydrology Experiment (IPHEx) field campaign took place from 01 May to 15 June 2014 in the southeastern US and centered on the Southern Appalachian Mountains (SAM). IPHEx was one of the ground validation campaigns after NASA’s Global Precipitation Mission (GPM) core satellite launch. Precipitation and aerosol measurements were collected and operated simultaneously at a supersite in the inner mountain region during the IPHEx IOP. Other supersite instrumentation included two radars (W- and X-band), a ceilometer, and a microwave radiometer. The University of North Dakota (UND) Citation Research Aircraft was flown to characterize aerosol and cloud microphysics’ vertical structure, including liquid water content, and hydrometeor-size distributions over the ground sites. This data set offers a great opportunity to perform modeling studies of warm-season cloud formation, leading to precipitation in complex terrain. I will first discuss the regional climatology of clouds and precipitation, including their role in modulating SAM’s hydrology and ecology. Second, we will investigate aerosol-cloud-precipitation interactions (ACPI) leveraging IPHEx IOP observations and two different models: (1) a cloud-parcel model to focus on aerosol-cloud interactions, and (2) a numerical weather prediction model—specifically weather research and forecasting (WRF)—to assess the impact of aerosol properties on precipitation over the SAM. Finally, we synthesize and examine our findings’ implications for the measurement and modeling of orographic precipitation processes generally
Modeling Vadose Zone Processes using HYDRUS and its Specialized Module
October 14, 2020
Dr. Jirka Šimůnek | October 14, 2020
Agriculture is one of the most important non-point pollution sources due to the use of chemicals in plant and animal production. Many mathematical numerical models evaluating water flow and the fate and transport of these chemicals in the subsurface were developed over the last three or four decades. These models are now readily available and widely used. This presentation will first briefly review recent versions of the HYDRUS models widely used to model water flow, chemical movement, and heat transport through variably-saturated soils. I will discuss various specialized HYDRUS modules intended to simulate processes not available in the standard HYDRUS versions, such as the transport of multiple interacting solutes, preferential flow, colloid-facilitated solute transport, cosmic ray fluxes, or transport of fumigants. These new modules include the DualPerm, C-Ride, HP1/2/3, Wetland, UnsatChem, Fumigant, Cosmic, Furrow, and Slope3. Finally, I will briefly review many recent applications of the Hydrus models, which include modeling of various irrigation practices, different contaminants, and different cropping systems.
The Work-4-Water Initiative: Promoting Workforce Development, Infrastructure Investment, 400 Cesspool Replacements and Water Protection in Hawai‘i’s Four Counties
Stuart Coleman and Michael Mezzacapo | September 30, 2020
To help Hawai‘i deal with the unprecedented COVID-19 and resulting hardships, the Work-4-Water Initiative aims to create a workforce of development projects, and in the process, reduce the amount of pollution from cesspools and support statewide resilient economic and community recovery plans. With more than 88,000 cesspools discharging nearly 53 million gallons of untreated sewage into the ground each day, Hawai‘i has been struggling for years to find solutions to its numerous wastewater issues. The Work-4-Water Initiative provides the state an immediate opportunity to jump-start the mandated replacement of cesspools, while simultaneously training and employing a specialized, non-tourism based workforce. Our plan will create shovel-ready projects across the state, stimulating the economy, and improving water quality and public health for residents and visitors alike through education, hands-on training, job creation, and pilot testing of more than 400 cesspool conversion sites on Hawai‘i, Maui, Kaua‘i, and O‘ahu.
Simulating Impacts of Land Cover Change and Climate Change on Groundwater Recharge in Maui
February 14, 2020
Dr. Laura Brewington | February 14, 2020
The objective of this study was to develop an integrated land cover/hydrological modeling framework using remote sensing and geographic information systems (GIS) data, stakeholder input, climate information and projections, and empirical data to estimate future groundwater recharge on the island of Maui, Hawaiʻi. Four future land-cover scenarios and two downscaled climate projections were used to estimate the end of the century mean annual groundwater recharge. The future scenarios focus were (1) conservation, (2) maintaining the status quo, (3) development, and (4) balancing conservation and development. The downscaled climate projections developed were (1) “dry future climate” and (2) “wet future climate.” To understand how the changing land management and climate could influence groundwater recharge, the results were compared to the estimated recharge using the 2017 baseline land cover. The estimated recharge increased island-wide under all future land-cover and climate combinations and was dominated by specific land cover transitions. To better describe the availability of groundwater across Maui, the water-budget modeling framework presented in this study provided information on the “supply” side, while the numerical groundwater modeling approach incorporated the “demand” side. Based on our findings, a spatially explicit scenario planning process and modeling framework would be able to communicate the possible consequences and tradeoff of land cover change under a changing climate, and can serve as a relevant tool for landscape-level management and decision making.
Working Together: Using Cloud-Based Collaborative Platforms to Facilitate Hydrologic Modeling and Data Analysis
Dr. Christopher Shuler | January 31, 2020
Recent advancements in social networking have influenced how we communicate professionally, how we work collaboratively, and how we approach data-science. Scientific endeavors—especially computational tasks such as groundwater modeling or exploratory data analysis—are poised to take advantage of these new developments. Improving the shareability of information has revolutionized how we work with each other, and revealed a new process-based paradigm that promotes enhanced collaboration and maintenance of long-standing project partnerships. In this presentation I’ll talk about my experiences using various cloud-based platforms such as GitHub and Google Colab to share data and work with researchers and stakeholders on hydrologic projects throughout Hawai‘i and American Samoa. These projects include the continuing development of a collaborative groundwater modeling framework with a water utility in American Samoa; using free google-based tools to manage a multi-disciplinary, statewide effort to understand the effects of non-point wastewater pollution on our coasts; and developing an open-access water budget model that is being used by multiple stakeholders to fill different needs.
Water Impacts of Invasive Plants in Hawai‘i
Speaker: Dr. Tom Giambelluca | November 5, 2019
Replacement of native plants by non-native invasive species can affect water processes and impact water resources in several ways. Perhaps the most important effect of invasion is the possible increase in transpiration by fast-growing invasive plants, leading to a greater proportion of water input being lost to the atmosphere as evapotranspiration. Invasive plants in Hawai‘i are widely believed to use more water (i.e., to have higher transpiration rates) than the native plants they replace. If true, this would mean that the widespread invasion of Hawai‘i’s ecosystems by non-native plants is having a big negative impact on our water resources by reducing streamflow and groundwater recharge. However, the research to demonstrate the effect of invasion on evapotranspiration is still relatively limited. In this presentation, I will discuss the reasons why invasive plants might be big water users and show the results of our field observations of transpiration and total evaporative water loss in native- and non-native-dominated ecosystems.
WATER ACCOUNTING FOR THE STATE OF HAWAI‘I: RESULTS FROM O‘AHU AND MAUI
Dr. Kirsten Oleson | October 22, 2019
In this project, we inventoried and assessed the stocks and flows of freshwater in Hawai‘i’s natural systems and human economy, following the integrated approach proposed by the United Nations’ System of Environmental-Economic Accounts for Water. In partnership with potential users of this information and providers of the data, as well as national and international experts, we developed reporting protocols and accounting tables for the Hawaiian Islands that are consistent with national level methods. They include (1) compiling integrated hydrological-economic water supply and use, and asset accounts; (2) identifying data gaps and next steps; and (3) raising awareness of accounting as a tool for sustainable management. The resulting island-scale water supply, use tables, and asset accounts detail stocks and flows between the environment and the economy for the two islands (O‘ahu and Maui). The products can serve as a clarifying guide to make fundamental choices about Hawai‘i’s various paths to economic development. The research can directly inform difficult choices about the water-energy-food nexus critical to Hawai‘i’s sustainability and security.
SUPPORTING CLIMATE CHANGE DECISION MAKING: DATA TRANSFORMATION AND KNOWLEDGE EXCHANGE WITH RESOURCE MANAGERS IN THE PACIFIC ISLANDS
Dr. Abby Frazier | October 8, 2019
Land managers are facing co-occurring threats to their landscapes such as climate change, invasive species, wildfire, and drought. As novel ecosystems and climates emerge—particularly hotter and drier climates—it is critical that scientists produce locally relevant, timely, and actionable science products. Trends in rainfall and characteristics of drought have been analyzed for the State of Hawai‘i since 1920, and additional high-resolution climate datasets have been recently produced (e.g., 25 years of gridded daily rainfall and temperature). However, the ability to use GIS is needed to extract site-specific information as no geospatial tools have been developed. For future climate projections, only raw climate model outputs are available for users. A knowledge exchange and technical assistance process is needed to encourage formal collaboration between researchers and managers. To address this need, we are piloting a knowledge exchange and technical assistance process with individual land managers in Hawai‘i and the U.S.-Affiliated Pacific Islands to co-produce customized site-specific drought and climate data products based on the needs of each manager. To improve the accessibility of the downscaled climate projections in Hawai‘i, the raw outputs have been re-processed and transformed into derived variables in raster format and standardized across models. This often-overlooked role of translating scientific outputs into usable, accessible data formats and engaging resource managers in research planning and knowledge co-production is essential to enable and support informed climate change decision making.
NATURAL AND CONTAMINANT CHEMISTRY OF FRESHWATER STREAMS, GROUNDWATER, AND WASTEWATER TREATMENT PLANT EFFLUENTS ON THE HAWAIIAN ISLANDS
Dr. Larry Barber | September 24, 2019
Sustainability of freshwater resources on island ecosystems relies on a detailed understanding of the sources and loading of contaminants and their impact on water quality. Considerable attention has been given to constituents such as nutrients and bacteria, but less is known about the occurrence and sources of unregulated contaminants such as trace elements and consumer product chemicals (pharmaceuticals and personal care products). Between 2014 and 2016 the U.S. Geological Survey conducted a survey of Hawaiian freshwaters on the islands of Kauai, Oahu, Maui, and Hawaii to assess the inorganic and organic chemistry of surface water and groundwater systems. This survey provides an important benchmark of the occurrence and sources for a variety of contaminants that are not typically investigated.
HYDROLOGICAL MODELING CHALLENGES IN HAWAII AND THE PACIFIC
Dr. Aly I. El-Kadi | September 13, 2019
Hydrological modeling in Hawaii and similar areas is challenging due to complicated hydrogeological features, steep topography, and variable climate conditions. This presentation will discuss the modeling efforts of the hydrology group over the past decades. Specifically covered include effects of climate change on Heeia watershed, American Samoa groundwater sustainability, surface water harvesting, and modeling of local scale geological variability. Progress of the current ‘Ike Wai modeling for West Hawaii’s groundwater will be also covered. Model developments are derived by the scale of the problem, data availability, and modeling objectives.
EVALUATING THE EFFECTS OF FUTURE CLIMATE AND LAND-COVER CONDITIONS ON GROUNDWATER RESOURCES FOR THE ISLAND OF MAUI, HAWAI‘I
Drs. Victoria Keener, Laura Brewington, and Alan Mair | April 23, 2019
Part I. Participatory Scenario Planning for Climate Change Adaptation: Projected Future Climate and Stakeholder-Defined Land-Cover Scenarios for the Island of Maui, Hawai‘i —Victoria Keener and Laura Brewington (East-West Center & NOAA Pacific Regional Integrated Sciences & Assessments)
Abstract: For the last century, the island of Maui has been the center of environmental, agricultural, and legal conflict with respect to both surface and groundwater allocation. Planning for sustainable future freshwater supply in Hawai‘i requires adaptive policies and decision-making that emphasizes private and public partnerships and knowledge transfer between scientists and non-scientists. To quantify future changes in an island-scale climate and groundwater recharge under different land uses, we will discuss downscaled dynamical and statistical future climate projects used in a participatory scenario building process. The participatory scenario planning began in 2012, bringing together a diverse group of ~100 decision-makers in government, watershed restoration, agriculture, and conservation to (1) determine the type of information they would find helpful in planning for climate change, and (2) develop a set of nested scenarios that represent alternative climate and management futures. This integration of knowledge is an iterative process, resulting in flexible and transparent narratives of complex futures comprised of information at multiple scales. We will present an overview of the downscaling, scenario building, and stakeholder response.
Part II. Groundwater Recharge for Projected Future Climate and Stakeholder-Defined Land-Cover Scenarios for the Island of Maui, Hawai‘i —Alan Mair (USGS Pacific Islands Water Science Center)
Abstract: Groundwater availability on Maui can be affected by changes in climate and land cover. To evaluate the availability of fresh groundwater under projected future climate and stakeholder-defined land-cover conditions, estimates of groundwater recharge are needed. As such, a water-budget model developed by the U.S. Geological Survey was used to estimate the spatial distribution of recharge for 11 unique combinations of climate and land-cover conditions. A variety of available research material was used in this study to represent the diversity of conditions, including two sets of end-of-century climate projects developed by University of Hawai‘i researchers, and future land-cover scenarios developed by Pacific RISA researchers. In one combination of climate and land-cover conditions, the results of the water budget for two future climate scenarios indicated a decrease across central and leeward areas of Maui, increases across windward areas of Haleakala, and opposing changes for the remaining parts of Maui. The projected changes in recharge for the future land-cover scenarios do suggest that appropriate land management may help to mitigate the effects of a drying climate.
CHARACTERIZING THE STREAM AND ITS ASSOCIATION WITH THE ECOSYSTEM IN HAWAI‘I
Dr. Yin-Phan Tsang | April 16, 2019
This presentation will consist of two parts, based on recent studies focusing on Hawaiian streams and ecosystems.
Part I. Characterizing Natural Barriers to Non-native Stream Fauna in Hawai‘i—Waterfalls are natural barriers that influence the distribution and dispersion of aquatic species. In Hawai‘i, it is assumed that non-native species are unable to pass waterfall barriers, yet they are still present above some waterfalls, possibly facilitated by human introduction. In this study, we used a landscape approach to identify likely human introductions and examined the ability of 14 non-native stream fauna to bypass waterfalls when the possibility of human introduction is eliminated. This study highlights the role that people play in facilitating species introductions in otherwise inaccessible habitats.
Part II. Temporal Shifts in the Magnitude of Peak Streamflow and Its Associated Rainfall Across the Hawaiian Islands—Previous studies show that extreme rainfall events are becoming more common. However, there is little research available that examines the temporal and spatial trends of peak streamflow (peak flow) events associated with heavy rainfall events. We analyzed the annual peak flow and the annual maximum rainfall trends of 112 stream crest gages from the U.S. Geological Survey, and an additional 82 rain gages from the National Centers for Environmental Information, across the Hawaiian Islands from the water years 1970 to 2005. To add to the current knowledge of flood risk and management in Hawai‘i, our study discussed how the annual peak flows changed over time, patterns in their spatial distribution, and how they are associated with rainfall.
*Please note, due to technical circumstances, the audio was unable to be captured during the video presentation below. We apologize for any inconvenience.*
CHALLENGES IN EVALUATING MICROBIAL BEACH WATER QUALITY IN HAWAI‘I
Dr. Marek Kirs | April 2, 2019
Abstract: In an effort to improve current water quality monitoring programs, the Water Resources Research Center has been engaged in multiple research projects pertaining to microbial water quality indicators, specifically in a tropical environment. This presentation will summarize the results of selected projects from 2013 to 2019. The projects addresses two major issues hampering the application of the EPA recommended Recreational Water Quality Criteria in Hawai‘i: (1) the growth of the current microbial water quality indicators in extra-enteric environments (i.e., soils and vegetation), and (2) the lack of information on contamination sources when the microbial water quality indicators are detected. My presentation will focus on the following, as it applies to Hawai‘i: (1) our current efforts to determine the health risk associated with current and alternative microbial water quality indicator levels, (2) the evaluation and application of molecular microbial source tracking (MST) methods, (3) the evaluation and application of rapid EPA method 1609 and 1611 for beach notification purposes, (4) utilization of a portable multi-use automated concentration system (PMACS) for the MST in our coastal environments, and (5) the hidden bacterial diversity in our groundwater.
ESTIMATION OF EVAPOTRANSPIRATION AND GROSS PRIMARY PRODUCTIVITY VIA VARIATIONAL ASSIMILATION OF REMOTELY SENSED LAND SURFACE TEMPERATURE AND LEAF AREA INDEX
Dr. Sayed Bateni | January 22, 2019
To estimate evapotranspiration and gross primary productivity, land surface temperature (LST) and leaf area index (LAI) measurements were assimilated into a coupled surface energy balance-vegetation dynamic model (SEB-VDM) within a variational data assimilation (VDA) system. The SEB and VDM are coupled by relating photosynthesis in the VDM to transpiration in the SEB equation. The unknown parameters of the VDA system are (1) bulk heat transfer coefficient (CHN), (2) soil evaporative fraction (EFs), (3) canopy evaporative fraction (EFc), and (4) specific leaf area (cg). The performance of the VDA approach was tested in the Heihe River Basin (HRB) extensively, which is located in northwest China. The results show that the developed VDA framework performs well in different environmental conditions, and the estimated evapotranspiration and gross primary productivity agree well with the corresponding measurements from the eddy covariance stations.