David A. Harpman

A MANAGED FLOOD ON THE COLORADO RIVER: BACKGROUND, OBJECTIVES, DESIGN, AND IMPLEMENTATION

The Colorado River ecosystem in lower Glen Canyon and throughout Marble and Grand Canyons was greatly altered following closure of Glen Canyon Dam in 1963, as flood control and daily fluctuating releases from the dam caused large ecological changes. Ecosystem research was conducted from 1983 through 1990, and intensively from 1990 through 1995 when dam releases were modified both for scientific purposes and protection of the river ecosystem. High flows (e.g., beach/habitat building flows) were included in the Glen Canyon Dam Environmental Impact Statement (EIS), which identified a preferred strategy for dam operations and protection of the downstream ecosystem. Use of high flows partially fulfills recommendations of many river and riparian scientists for return of more natural flows, as part of initial efforts in river restoration. In 1996, a seven-day experimental controlled flood was conducted at Glen Canyon Dam to closely study the effects of a high flow event equivalent to those proposed for future da...

A methodology for quantifying and valuing the impacts of flow changes on a fishery

A quasi-population model for adult brown trout was developed for the Taylor River below the Taylor Park Reservoir in Colorado. This model allows the population to be predicted under alternative flow management regimes. The predicted population effects of two different flow release patterns were compared with the predicted population for the current reservoir operation regime. Changes in angler catch were imputed for these scenarios. The changes in catch were valued using estimates of willingness to pay obtained from anglers fishing at the site. Total angling effort was held constant. For both of the flow scenarios examined the difference in economic use value was limited. The relatively small changes in value predicted were shaped by the small changes in catch predicted and the high number of fish caught under current conditions.

The Potential of Agent-Based Modelling for Performing Economic Analysis of Adaptive Natural Resource Management

Abstract This paper explores how individual agent-based modelling can be used by economists and others to evaluate the economic aspects of adaptive management of natural resources. To date, economists have had few tools to perform economic analysis on adaptive natural resource management strategies and there has been limited economic analysis of adaptive management. Part of the reason for this situation may be the inherent nature of adaptive management which involves a series of ‘if-then’ in situ experiments in which expected outputs are not known with certainty, and future management actions depend on the outcome of the experiments. Individual agent-based modelling allows simulation of system wide emergent ecosystem properties that can reflect adaptation of individual agents with bounded rationality to their environment and to the interaction with other agents. These simulations can be used to mimic adaptive management experiments when insufficient information is available for more structured equation-based simulation models. The distribution of simulated outputs from individual agent-based models along with costs of the management actions may give economists the ability to better apply economic analysis to evaluate alternative adaptive management strategies.

Lake Powell Management Alternatives and Values: CVM Estimates of Recreation Benefits

Abstract This paper presents data analyses based on information gathered from a recreation survey distributed during the spring of 1997 at Lake Powell. Recreation-linked management issues are the foci of the survey and this discussion. Survey responses to contingent valuation method (CVM) queries included in the questionnaire quantify visitor recreation values. The CVM estimates of the benefits provided by potential resource improvements are compared with the costs of the improvements in a benefit-cost analysis. The CVM questions covered three resources management issues including water quality improvement, sport fish harvest enhancement, and archeological site protection and restoration. The estimated benefits are remarkably high relative to the costs and range from

Unit Non-Response Bias in the Interval Data Model

6 to

WESTERN WIND AND SOLAR INTEGRATION STUDY HYDROPOWER ANAYSIS: BENEFITS OF HYDROPOWER IN LARGE-SCALE INTEGRATION OF RENEWABLES IN THE WESTERN UNITED STATES

60 million per year. The dichotomous choice format was used in each of three resource CVM question scenarios. There were two levels of enhancement for each resource. There are, therefore, several consistency requirements—some of them unique to the dichotomous choice format—that the data and benefit estimates must satisfy. These consistency tests are presented in detail in the ensuing analysis.

The Voluntary Nongame Check-Off as a Revenue Source

A mail survey was administered to a panel of Colorado consumers to obtain estimates of willingness to pay (WTP) for preserving Union Park. Detailed socioeconomic data for all surveyed individuals was available a priori. We develop and employ the multiple-bounded probit with selection (MBPS) model, to correct for non-response and self-selection bias. Statistical tests indicate estimates of WTP corrected for these biases are significantly higher than uncorrected estimates. The use of selection models requires an additional investment by researchers. These investments may be warranted for policy relevant studies. (JEL Q26)

Economic Benefits and Costs of Stocking Catchable Rainbow Trout: A Synthesis of Economic Analysis in Colorado

NREL and research partner GE are conducting the Western Wind and Solar Integration Study (WWSIS) in order to provide insight into the costs and operational impacts caused by the variability and uncertainty of wind, photovoltaic, and concentrated solar power employed to serve up to 35% of the load energy in the WestConnect region (Arizona, Colorado, Nevada, New Mexico, and Wyoming). The heart of the WWSIS is an hourly cost production simulation of the balancing areas in the study footprint using GE’s Multi-Area Production Simulation Model (MAPS). The estimated 2017 load being served is 60 GW, with up to 30 GW of wind power and 4 GW of existing hydropower. Because hydropower generators are inherently flexible and often combined with reservoir storage, they play an important role in balancing load with generation. However, these hydropower facilities serve multiple higher priority functions that constrain their use for system balancing. Through a series of comparisons of the MAPS simulations, it was possible to deduce the value of hydropower as an essential balancing resource. Several case comparisons were performed demonstrating the potential benefits of hydro and to ascertain if the modeled data was within the defined hydro parameters and constraints. The results, methodologies, and conclusions of these comparisons are discussed, including how the hydro system is affected by the wind power for different wind forecasts and penetration levels, identifying the magnitude and character of change in generation pattern at each of the selected hydro facilities. Results from this study will focus on the appropriate benefits that hydropower can provide as a balancing resource including adding value to wind and solar and reducing system operating costs to nearly one billion dollars when offsetting more expensive generation systems as large penetration levels of renewable, especially wind power, are introduced to the grid system.Copyright

Assessing the Short-Run Economic Cost of Environmental Constraints on Hydropower Operations at Glen Canyon Dam

Thirty-two of the 40 states with broad-based income taxes are now using voluntary Abstract check-offs on their tax returns as a way of soliciting contributions for nongame wildlife programs and other activities. This study uses both individual and aggregate data to examine the factors that influence check-off contributions. Income and the number of other check-offs on the tax form were among the major determinants. An appraisal of the check-off suggests that the tendency to add more check-offs to the tax return quickly erodes its revenue productivity. Furthermore, the check-offis open to serious questions about its fairness.