Christopher Wada
Benefit-Cost Analysis of Watershed Conservation
The objectives of this report are (1) to review studies that estimate the relationship between watershed conservation activities and groundwater recharge in Hawai‘i and (2) to estimate the volume of freshwater yield saved per dollar invested in conservation at several sites on Hawai‘i Island. We conclude from the literature review that more work should be […]
Read MoreThe Economic Impact of Astronomy in Hawai‘i
The astronomy sector in Hawaii generates economic activity through its purchases from local businesses, its payment to its employees, and spending by students and visitors. In collaboration with the Institute for Astronomy, a survey was designed to obtain information from astronomy related entities about in-state expenditures. The collected survey data was used to estimate the […]
Read MoreBenefits and Costs of Implementing the IAPMO Green Plumbing and Mechanical Code Supplement in Hawaii
We calculate the benefits and costs of implementing the International Association of Plumbing and Mechanical Officials (IAPMO) 2012 Green Plumbing and Mechanical Code Supplement (GPMC) for various building types in Hawaii, with particular emphasis on water-use efficiency provisions in the code. Benefits of the GPMC are measured as water savings, where baseline usage is estimated […]
Read MoreEnergy, Backstop Endogeneity, and the Optimal Use of Groundwater
To meet the growing demand for freshwater, many regions have increased groundwater pumping in recent years, resulting in declining groundwater levels worldwide. A promising development to address these declines is technical change regarding groundwater substitutes such as desalination and wastewater recycling. However, because these technologies are energy intensive, optimal implementation also depends on future energy […]
Read MoreHow Do We Manage Our Interdependent Environmental Resources?
By Christopher Wada Managing water resources requires an understanding of the linkages between key hydrologic factors and direct human influences. The problem is further complicated by the fact that water resources are often interdependent, which suggests that management should also account for ecological interlinkages. For example, a forested upstream watershed may replenish an underlying groundwater […]
Read MoreIncentivizing interdependent resource management: watersheds, groundwater, and coastal ecology
Managing water resources independently may result in substantial economic losses when those resources are interdependent with each other and with other environmental resources. We first develop general principles for using resources with spillovers, including corrective taxes (subsidies) for incentivizing private resource users. We then analyze specific cases of managing water resources, in particular the interaction […]
Read MoreGroundwater Economics without Equations
In many parts of the world, irrigation and groundwater consumption are largely dependent on groundwater. Minimizing the adverse effects of water scarcity requires optimal as well as sustainable groundwater management. A common recommendation is to limit groundwater extraction to maximum sustainable yield (MSY). Although the optimal welfare-maximizing path of groundwater extraction converges to MSY in […]
Read MoreOptimal Joint Management of Interdependent Resources: Groundwater vs. Kiawe (Prosopis pallida)
Local and global changes continue to influence interactions between groundwater and terrestrial ecosystems. Changes in precipitation, surface water, and land cover can affect the water balance of a given watershed, and thus affect both the quantity and quality of freshwater entering the ground. Groundwater management frameworks often abstract from such interactions. However, in some cases, […]
Read MoreThe Good, Bad, and Ugly of Watershed Management
Efficient management of groundwater resource systems requires careful consideration of relationships — both positive and negative — with the surrounding environment. The removal of and protection against “bad” and “ugly” natural capital such as invasive plants and feral animals and the enhancement of “good” capital (e.g. protective fencing) are often viewed as distinct management problems. […]
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