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Identifying priority watershed management areas for groundwater recharge protection on Hawai‘i Island

Identifying priority watershed management areas for groundwater recharge protection on Hawai‘i Island

Identifying priority watershed management areas for groundwater recharge protection on Hawai‘i Island

Identifying priority watershed management areas for groundwater recharge protection on Hawai‘i Island

Identifying priority watershed management areas for groundwater recharge protection on Hawai‘i Island

Identifying priority watershed management areas for groundwater recharge protection on Hawai‘i Island

Charting a New Fiscal Course for Hawaii: A Fiscal Architecture Approach

Charting a New Fiscal Course for Hawaii: A Fiscal Architecture Approach

Charting a New Fiscal Course for Hawaii: A Fiscal Architecture Approach

Annual Hawaii Forecast with Global Outlook: After a Cloudy 2019, New Year Looks a Bit Brighter


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Identifying priority watershed management areas for groundwater recharge protection on Hawai‘i Island

This report provides an analysis of the relative effectiveness of watershed conservation and restoration efforts in terms of groundwater recharge benefits in Hawaiʻi County Department of Water Supply (DWS) priority aquifers and recharge areas. In Kohala, Kona, and Kaʻū. With financial support from DWS and the National Science Foundation, EPSCoR ʻIke Wai project, this study builds upon a previous effort funded by the Hawaiʻi Community Foundation (HCF). Specifically, this report extends the previous report for HCF by: 1) expanding the area of interest to include priority recharge areas as well as target aquifers identified by DWS; 2) including an analysis of potential spread of non-native grassland into native forest areas; 3) including an analysis of changes in potential fog interception with change in land cover; and 4) adding an assessment of priority areas for native forest restoration.

UHERO Report

 


Do natural disasters make sustainable growth impossible?

We consider the prospects for sustainable growth using expected utility models of optimal investment under threat from natural disasters. Adoption of a continuous time, stochastic Ramsey growth model over an infinite time horizon permits the analysis of sustainability under uncertainty regarding adverse events, including both one-time and recurrent disasters. As appropriate to small economies, we consider adaptation to the risk of disaster. Natural disasters reduce capital stocks and disrupt the optimal consumption and felicity paths. While the time path of inter-temporal welfare might consequently shift downward, the path may still be non-decreasing over time, even without adding strong or weak sustainability constraints. Prudent disaster preparedness includes precautionary investment in productive capital, programs of adaptation to disaster risk, and avoiding distortionary policies undermining the prospects of optimality and sustainability.

Published: https://link.springer.com/article/10.1007/s41885-019-00054-y

Working Paper


Characterizing Hawai‘i’s Natural Resources Management Sector

This report provides an update to the 2015 “Recent Trends in Hawai‘i’s Green Economy: Agriculture, Energy, and Natural Resource Management” publication, the second update since our original report in 2012. Hawai‘i’s natural resource management jobs were at least 4,697 in 2018, 33% higher than reported for 2014, which is equivalent to an annual growth rate of roughly 7%.

According to survey data, Hawai‘i’s natural resource management expenditures were at least $542 million in 2018, roughly equal to expenditures reported for 2014.

UHERO Report

 


Identifying Areas of Cost-effective Watershed Management for Groundwater Recharge Protection on Hawai‘i island

In collaboration with the County of Hawai‘i Department of Water Supply (DWS), we identified three priority management areas on Hawai‘i Island: Kohala, Kona, and Kaʻū. These critical recharge areas were identified by DWS as important recharge areas for four aquifers where current withdrawals are near current or future sustainable yield limits: Mahukona, Waimea, Keauhou, and Kealakekua. We then developed a statistical model to assess how land cover change would affect evapotranspiration and subsequently groundwater recharge—building off existing evapotranspiration, climate, land cover, and recharge datasets—to identify areas of high potential recharge benefits within the priority areas following forest protection activities. Cost data from nearby watershed management units were used to calculate average management costs for each priority area, and then were combined with the potential recharge benefit map to generate a map of cost-effectiveness.

UHERO Report

 


Economic Valuation of The Nature Conservancy’s Watershed Conservation Activities in Waikamoi Preserve, Maui

The objective of this research was to estimate the value of ecosystem services protected by watershed conservation activities at The Nature Conservancy’s Waikamoi Preserve on the island of Maui. Projections of monetized benefits, together with trajectories of conservation costs, were used to calculate net present value, payback period, and return on investment.

UHERO Report

 


Bringing multiple values to the table: assessing future land-use and climate change in North Kona, Hawaiʻi

As ecosystem service assessments increasingly contribute to decisions about managing Earth’s lands and waters, there is a growing need to understand the diverse ways that people use and value landscapes. However, these assessments rarely incorporate the value of landscapes to communities with strong cultural and generational ties to place, precluding inclusion of these values—alongside others—into planning processes. We developed a process to evaluate trade-offs and synergies in ecosystem services across land-use scenarios and under climate change in North Kona, Hawaiʻi, a tropical dry ecosystem where water, fire, biodiversity, and cultural values are all critical considerations for land management decisions. Specifically, we combined participatory deliberative methods, ecosystem service models, vegetation surveys, and document analysis to evaluate how cultural services, regulating services (groundwater recharge, landscape flammability reduction), biodiversity, and revenue: (1) vary across four land-use scenarios (pasture, coffee, agroforestry, and native forest restoration) and (2) are expected to vary with climate change (representative concentration pathway (RCP) 8.5 mid-century scenario). The native forest restoration scenario provided high cultural, biodiversity, and ecosystem service value, whereas coffee's strongest benefit was monetary return. The agroforestry scenario offered the greatest potential in terms of maximizing multiple services. Pasture had relatively low ecological and economic value but, as with native forest and agroforestry, held high value in terms of local knowledge and cultural connection to place. Climate change amplified existing vulnerabilities for groundwater recharge and landscape flammability, but resulted in few shifts in the ranking of land-use scenarios. Our results demonstrate that cultural services need not be sacrificed at the expense of other management objectives if they are deliberately included in land-use planning from the start. Meaningfully representing what matters most to diverse groups of people, now and under a changing climate, requires greater integration of participatory methods into ecosystem service analyses.

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Joint Management of an Interconnected Coastal Aquifer and Invasive Tree

Kiawe (Prosopis pallida), a mesquite tree considered invasive in many parts of the world including Hawai‘i, has been shown to reduce regional groundwater levels via deep taproots. In areas where aquifers are primary sources of fresh water, kiawe control has the potential to be an integral component of water management planning. We develop an analytical dynamic framework for the joint management of kiawe and groundwater, and show that optimal water management depends on expected kiawe damages, while optimal kiawe removal depends on groundwater scarcity and removal cost. Using data from the Kīholo aquifer on the west coast of Hawai‘i Island, we solve for joint management decisions with corresponding parameters related to kiawe damage and water scarcity. With 1.5% water demand growth, Kiawe should be removed if the removal cost is below $1,884/ha. Our numerical results indicate that kiawe damage is nonlinear in the rate of water demand growth. The damage costs can be attributed to three main factors. When demand growth is low, kiawe damage is driven by a higher water extraction cost. For moderate growth, the effect is compounded by anticipated future scarcity. Damage is amplified by a backstop cost effect when the growth rate is high.

Working Paper


Estimating Cost-Effectiveness of Hawaiian Dry Forest Restoration Using Spatial Changes in Water Yield and Landscape Flammability Under Climate Change open access

New research published in Pacific Science from an interdisciplinary team including UHERO's Christopher Wada, Leah Bremer, and Kim Burnett identifying cost-effective watershed restoration for multiple ecosystem service benefits in Pu‘u Wa‘awa‘a on the island of Hawai‘i.

READ

 


Do Natural Disasters Make Sustainable Growth Impossible?

We consider the prospects for sustainable growth using expected utility models of optimal investment under threat from a natural disaster. Extension of a discrete, two-period model, to continuous time over an infinite time horizon permits the analysis of sustainability under uncertainty regarding adverse events, including both one-time and recurrent disasters. Natural disasters, with destruction of productive capital, disrupt the optimal consumption and utility paths, but the Arrow et al. (2004) sustainability criterion is still satisfied even without adding strong or weak sustainability constraints. We also consider a separate natural resource sector and show that, except for extreme cases, the optimal steady state level of the renewable resource is not affected by the possibility of natural disasters. In the case of catastrophic events, however, damage to the resource system may be severe enough to push the system below a critical value tipping point, undermining the prospects of long-run sustainability.

WORKING PAPER


Assessing the Costs of Priority HISC Species in Hawaii

Over the past decade, funding for the Hawaii Invasive Species Council (HISC) has ranged from less than $2 million per year in the three years following the recent economic downturn, up to almost $6 million in FY2015. The HISC website provides total award amounts for past projects, but it is difficult to attribute exact dollar amounts to specific species for projects that target multiple species. As a starting point, we consider the number of times each invasive species was designated as a target over the period FY2005-2015. While this list does not necessarily represent species that generated the largest economic damages or species for which the most spending has occurred, it is a list of species getting the most attention by HISC. For the most part, the top ten have remained fairly consistent over time, although in recent years, axis deer, albizia, and ivy gourd have received noticeably more attention.

PROJECT REPORT


Sustainable Agriculture Irrigation Management: The Water-Energy-Food Nexus in Pajaro Valley, California

The water-energy-food (WEF) nexus is quickly becoming one of the most critical global environmental challenges of the twenty first century. However, WEF systems are inherently complex; they typically are dynamic and span multiple land or agro-ecosystems at a regional or global scale. Addressing this challenge requires a systems approach to optimal and sustainable resource management across multiple dimensions. To that end, using Pajaro Valley (California) as a case study, our research aims to (1) highlight synergies and tradeoffs in food and water production, (2) build a dynamic framework capable of examining intertemporal resource relationships, and (3) detail the steps required to develop incentive-compatible financing of the resulting management plans when benefits are not distributed uniformly across users. Using a stylized model, we find that in the long run, inland growers benefit from the halting of seawater intrusion (SWI) due to overpumping of groundwater. We also calculate that the water provided by the proposed College Lake Multi-Objective Management Program—a plan designed to halt SWI and support sustainable water and agricultural development in the region—will generate net revenue of $40-58 million per year, compared to an annualized cost of less than $3 million. An equal cost-sharing plan would be desirable if the benefit of the project exceeded $1,268 per year for each well owner. Since this may not necessarily be the case for smaller well owners, one possible alternative is to allocate costs in proportion to expected benefits for each user.

WORKING PAPER


The Economic Value of Groundwater in Obama

Worldwide, freshwater is important not only for direct consumption but also for its role in the production of a variety of goods and services. For example, water is used for cooling nuclear reactors and as an input for the production of energy via hydroelectric processes. Freshwater also is essential for the production of food, including crops and livestock. Recognizing these synergies and identifying tradeoffs are key components of water-energy-food (WEF) nexus research (Taniguchi et al., 2013; Loring et al., 2013; Giampietro et al., 2014). In this study, we focus on Obama City, Japan, where groundwater is used directly for domestic and commercial consumption and for melting snow. Stored groundwater also provides an indirect benefit: submarine groundwater discharge (SGD) from the aquifer supports the nearshore ecology, including a locally important fishery. Using this case study, we document some common challenges that arise when undertaking WEF research and outline an example of an integrated approach that combines multiple modes of analysis to overcome those obstacles.

WORKING PAPER


Cost-Benefit Analysis of Disaster Mitigation Infrastructure: The Case of Seawalls in Otsuchi, Japan

Disaster management problems often pose the same types of challenges that environmental governance problems do; they involve decision-makers at various levels and can transcend political boundaries. We conduct a benefit-cost analysis of a disaster adaptation strategy in Otsuchi, which was undertaken shortly after the 2011 Tohoku earthquake and tsunami devastated the region. Results indicate that present value net benefits from the planned seawall are positive, even if expected damages are low, provided that the wall is capable of reducing damage by at least 50%. A hybrid method of governance may, however, be effective at increasing the benefit-cost ratio.

WORKING PAPER


Recent Trends in Hawaii's Green Economy: Agriculture, Energy and Natural Resource Management

This report provides an update to the 2012 “Foundations for Hawai‘i’s Green Economy: Economic Trends in Hawai‘i Agriculture, Energy, and Natural Resource Management.” Although economic information has long been collected for many sectors in Hawai‘i, including agriculture and energy, the 2012 project was the first to collect indicators specifically for the natural resource management (NRM) sector. With financial support from Hau‘oli Mau Loa Foundation and research assistance from The Nature Conservancy, the University of Hawai‘i Economic Research Organization was tasked with collecting and analyzing information from three sectors that are key to future sustainability in Hawai‘i - energy, agriculture and natural resource management.

project report


Methods of the Water-Energy-Food Nexus

This paper focuses on a collection of methods that can be used to analyze the water-energy-food (WEF) nexus. We classify these methods as qualitative or quantitative for interdisciplinary and transdisciplinary research approaches. The methods for interdisciplinary research approaches can be used to unify a collection of related variables, visualize the research problem, evaluate the issue, and simulate the system of interest. Qualitative methods are generally used to describe the nexus in the region of interest, and include primary research methods such as Questionnaire Surveys, as well as secondary research methods such as Ontology Engineering and Integrated Maps. Quantitative methods for examining the nexus include Physical Models, Benefit-Cost Analysis (BCA), Integrated Indices, and Optimization Management Models. The authors discuss each of these methods in the following sections, along with accompanying case studies from research sites in Japan and the Philippines. Although the case studies are specific to two regions, these methods could be applicable to other areas, with appropriate calibration.

Published version: Endo, A., K. Burnett, P. Orencio, T. Kumazawa, C. Wada, A. Ishii, I. Tsurita, and M. Taniguchi. 2015. Methods of the water-energy-food nexus. Water 7, 5806-5830.

WORKING PAPER


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