A NEW CHALLENGE FOR WESTERN WATER SUPPLIES1

ABSTRACT: In many of the limited water resource areas of the western United States most water supplies have been put to beneficial uses. Energy, a fast expanding high-priority water use, is making challenging demands for these limited supplies. Can water supplies be stretched, supplemented, or redirected so that present uses can be maintained and energy water needs satisfied? The Bureau of Reclamation is investigating innovative methods of water management, reregulation, and use to meet these demands. Related programs under study include potentials for: development of additional hydroelectric power, installation of low-head turbines in western water courses, utilization of pumped storage and underground storage, use of geo-thermal heat, extension of water supplies through more efficient irrigation systems and practices, and weather modification.     

USING MARYLAND'S STREAM CORRIDOR ASSESSMENT SURVEY TO PRIORITIZE WATERSHED RESTORATION EFFORTS1

ABSTRACT: The Stream Corridor Assessment survey has been developed by the Maryland Department of Natural Resources as a watershed management tool to identify environmental problems and to help prioritize restoration opportunities on a watershed basis. Potential environmental problems commonly identified during the survey include: stream channel alterations, excessive bank erosion, exposed pipes, inadequate stream buffers, fish migration blockages, trash dumping sites, near stream construction, pipe outfalls, and unusual conditions. In addition, the survey records information on the location of potential wetlands creation sites and collects data on the general condition of instream and riparian habitats. Over the past several years, in collaboration with the Maryland Conservation Corps, watershed associations, and local governments, more than 3,293 km (2,046 miles) of Maryland streams have been surveyed. Overall, the survey has proven to be a cost effective starting point for many watershed restoration efforts.     

Socioeconomic and Institutional Dimensions of Dam Removals: The Wisconsin Experience

/ There are tens of thousands of small dams in the United States; many of these aging structures are deteriorating. Governments and dam owners face decisions regarding repair or removal of these structures. Along with the many benefits society derives from dams and their impoundments, numerous recent ecological studies are revealing the extensive alteration and degradation of river ecosystems by dams. Dam removal-a principal restoration strategy-is an infrequent event. The major reasons for removal have been public safety and the high costs associated with repair; the goal of river ecosystem restoration now warrants greater attention. Substantial study is being given to the environmental aspects of dams and dam removals, but very little attention has been given to the socioeconomic and institutional dimensions associated with the removal of dams, although these factors play a significant role in the removal decision-making process. Based on a case study of dam removals in Wisconsin-where more than 30 of the state's 3600 small dams have been removed in the past few decades-legal, financial, and socioeconomic issues associated with dam removal are documented and assessed. Dam removal has been complex and contentious, with limited community-based support for removal and loss of the impounded waters. In cases examined here, the estimated costs of repairing a dam averaged more than three times the cost of removal. The availability of governmental financing has been a key determinant in removal decisions. Watershed-scale ecological considerations are not major factors for most local interests. As watershed management and restoration increasingly include dam removal options as part of an integrated strategy, more attention will need to be focused on socioeconomic factors and stakeholder perspectives-variables that strongly influence the viability of this management alternative.KEY WORDS: Dam removal; River restoration; Institutions; Stakeholders     

Effects of Exotic Lonicera and Rhamnus on Songbird Nest Predation

Abstract: Habitat fragmentation and disturbance exacerbate the invasion of exotic plant species that, in turn, may attract nesting songbirds by providing a branch structure suitable for nest sites. We document that American Robin ( Turdus migratorius ) nests in two exotic plants, Lonicera maackii and Rhamnus cathartica , experienced higher predation than nests built in comparable native shrubs ( Crataegus, Viburnum ) and native tree species. This was due to a combination of lower nest height, the absence of sharp thorns on the exotic species, and perhaps a branch architecture that facilitated predator movement among the exotic species. In a more subtle interaction, nesting Wood Thrushes ( Hylocichla mustelina ) experienced apparent competition with robins for nest sites in Lonicera , and this interaction was further aggravated by an increased selectivity for Lonicera by nesting robins, possibly due to their early leaf flush and expansion. By documenting increased nest predation in songbirds nesting in exotic shrubs, our results suggest that restoring native plant communities may benefit the surrounding avian community.     

Valuing externalities from water supply: Status quo,choice complexity and individual random effects in panel kernel logit analysis of choice experiments

Choice experiments are often implemented with choice sets including one alternative depicting the status quo. Utility from status quo is experienced by the respondent, while utility associated with experimentally designed hypothetical alternatives is only conjectured by respondents. The effects of explicitly accounting for such a difference in the econometric analysis of the data are often unreported, or limited to fitting a ‘status quo’ constant. The paper proposes a model that explicitly accounts for these effects and attempts their decomposition using data from two choice modelling exercises designed to value the provision of environmental goods. Preferences for change versus status quo are explored with standard specifications along with a less usually applied error component analysis via mixed logit. The results suggest that alternatives offering changes from status quo do not share the same preference structure as the status quo alternative, and that estimates of spread parameters in zero-mean error components can be decomposed conditional on respondents' socio-economic characteristics. It is argued that these findings have implications for practitioners and their stance towards the strategies for the econometric analysis of choice modelling data for the purpose of valuation.     

THE FOREST–HYDROLOGY–POVERTY NEXUS IN CENTRAL AMERICA: AN HEURISTIC ANALYSIS

A ‘forest–hydrology–poverty nexus’ hypothesis asserts that deforestation in poor upland areas simultaneously threatens biodiversity and increases the incidence of flooding, sedimentation and other damaging hydrological processes. This paper uses rough heuristics to assess the applicability of this hypothesis to two montane forested countries in Central America: Guatemala and Honduras. We do so by using simple rules of thumb to identify watersheds at greater risk of hydrologically significant land use change, using information about land cover, slope, and watershed size. The location of these watersheds is compared to spatial maps of poverty and forests. We find plausible evidence for a forest–biodiversity–poverty connection in Guatemala, and to a lesser extent in Honduras.