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• 1. [Article] A topography of dams in China : impacts to agriculture, labor, and migration

  Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, ...

  Citation × Citation Citation Abstract Copy Title: A topography of dams in China : impacts to agriculture, labor, and migration Author: Foster-Moore, Eric Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, remains contentious due to the potential for negative environmental and socioeconomic impacts. Despite numerous case studies, there is little systematic empirical evidence about either the contribution of dams to human development or their negative impacts to humans and the environment. Identifying the impact of dams also presents a methodological challenge because dam placement is likely endogenous to socioeconomic outcomes. The topographic suitability of a landscape for dam construction provides a source of exogenous variation in dam siting, which, building on the work of previous scholars, I exploit to identify the effect of large dams on agriculture, population change, and labor allocation. My results suggest that dams have decreased grain production in the counties where they were built and have drawn labor into non-agricultural fields. Dams appear to impact population subgroups in predictable ways and create identifiable winners and losers. Title: A topography of dams in China : impacts to agriculture, labor, and migration Author: Foster-Moore, Eric Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, remains contentious due to the potential for negative environmental and socioeconomic impacts. Despite numerous case studies, there is little systematic empirical evidence about either the contribution of dams to human development or their negative impacts to humans and the environment. Identifying the impact of dams also presents a methodological challenge because dam placement is likely endogenous to socioeconomic outcomes. The topographic suitability of a landscape for dam construction provides a source of exogenous variation in dam siting, which, building on the work of previous scholars, I exploit to identify the effect of large dams on agriculture, population change, and labor allocation. My results suggest that dams have decreased grain production in the counties where they were built and have drawn labor into non-agricultural fields. Dams appear to impact population subgroups in predictable ways and create identifiable winners and losers. Close

• 2. [Article] Will we need to change the rules : assessing the implications of climate change for dam operations in Oregon's McKenzie River Basin

  Dams and reservoirs are important components of water resource management systems, but their operational sensitivity to streamflow variability may make them vulnerable to climate change. Climate change ...

  Citation × Citation Citation Abstract Copy Title: Will we need to change the rules : assessing the implications of climate change for dam operations in Oregon's McKenzie River Basin Author: Danner, Allison G. Dams and reservoirs are important components of water resource management systems, but their operational sensitivity to streamflow variability may make them vulnerable to climate change. Climate change is likely to affect the magnitude and timing of streamflow, motivating the assessment of potential impacts on dams and reservoirs. Here I examine a case study of Cougar Dam, a multipurpose dam in Oregon, USA, to assess potential impacts of future climate change on operational performance. In the first portion of this study, I examine the historical operation of Cougar Dam, to understand (1), whether operational objectives have been achievable in the past despite operational variability, and (2) how climatic variation is expressed in operational trajectories. By analyzing historical streamflow and operations data using a set of metrics, I characterize variability in past operations and how that variability relates to streamflow. I also employ a reservoir model to distinguish operational differences due to streamflow variability from variability due to other factors that affect operations. I find that operational objectives have been achievable, despite variability in operations and departures from the ideal operational trajectory. Throughout the historical period, flood control operations have almost always kept reservoir outflows below the desired maximum outflow. Although filling occurs 9 days late on average, the reservoir has filled in all but 6 out of 37 years. Although drawdown occurs 47 days early on average, early drawdown does not generally impact recreation and allows minimum outflows to be met every day during all but the driest year. I also find that total seasonal inflow is correlated with measures of operational performance, and that other factors besides climate play an important role in determining operational trajectories. I conclude that operations of Cougar Reservoir are vulnerable to climate change, but that operational flexibility may mitigate some of the potential impacts. In the second portion of this study I assume that current operating rules will be kept in place and I aim to understand what types of operational impacts may be expected, when they may be expected to occur, and whether the operational impacts may necessitate changing operational rules. I employ both a traditional climate impacts assessment approach to assess changes over time as well as a scenario-neutral approach to generalize relationships between streamflow and operations of Cougar Dam. I find that projected increases in winter streamflow could result in up to twice the number of downstream high flows than in the past and that projected decreases in summer streamflow could result in earlier reservoir drawdown by up to 20 days on average. Additionally, filling of the reservoir may occur up to 16% more often or 11% less often than in the past, depending on spring flow magnitude and timing. I also find that there are strong general relationships between total inflow volume and flood control performance, and that there are total inflow thresholds for whether or not the reservoir will fill or will be full enough for recreation in late summer. I conclude that future modification of operating policies may be warranted, but that there will likely be tradeoffs between operating objectives in the future even if operating rules are modified. Title: Will we need to change the rules : assessing the implications of climate change for dam operations in Oregon's McKenzie River Basin Author: Danner, Allison G. Dams and reservoirs are important components of water resource management systems, but their operational sensitivity to streamflow variability may make them vulnerable to climate change. Climate change is likely to affect the magnitude and timing of streamflow, motivating the assessment of potential impacts on dams and reservoirs. Here I examine a case study of Cougar Dam, a multipurpose dam in Oregon, USA, to assess potential impacts of future climate change on operational performance. In the first portion of this study, I examine the historical operation of Cougar Dam, to understand (1), whether operational objectives have been achievable in the past despite operational variability, and (2) how climatic variation is expressed in operational trajectories. By analyzing historical streamflow and operations data using a set of metrics, I characterize variability in past operations and how that variability relates to streamflow. I also employ a reservoir model to distinguish operational differences due to streamflow variability from variability due to other factors that affect operations. I find that operational objectives have been achievable, despite variability in operations and departures from the ideal operational trajectory. Throughout the historical period, flood control operations have almost always kept reservoir outflows below the desired maximum outflow. Although filling occurs 9 days late on average, the reservoir has filled in all but 6 out of 37 years. Although drawdown occurs 47 days early on average, early drawdown does not generally impact recreation and allows minimum outflows to be met every day during all but the driest year. I also find that total seasonal inflow is correlated with measures of operational performance, and that other factors besides climate play an important role in determining operational trajectories. I conclude that operations of Cougar Reservoir are vulnerable to climate change, but that operational flexibility may mitigate some of the potential impacts. In the second portion of this study I assume that current operating rules will be kept in place and I aim to understand what types of operational impacts may be expected, when they may be expected to occur, and whether the operational impacts may necessitate changing operational rules. I employ both a traditional climate impacts assessment approach to assess changes over time as well as a scenario-neutral approach to generalize relationships between streamflow and operations of Cougar Dam. I find that projected increases in winter streamflow could result in up to twice the number of downstream high flows than in the past and that projected decreases in summer streamflow could result in earlier reservoir drawdown by up to 20 days on average. Additionally, filling of the reservoir may occur up to 16% more often or 11% less often than in the past, depending on spring flow magnitude and timing. I also find that there are strong general relationships between total inflow volume and flood control performance, and that there are total inflow thresholds for whether or not the reservoir will fill or will be full enough for recreation in late summer. I conclude that future modification of operating policies may be warranted, but that there will likely be tradeoffs between operating objectives in the future even if operating rules are modified. Close

• 3. [Article] Flow Management for Hydropower Extirpates Aquatic Insects, Undermining River Food Webs

  Published by Oxford University Press on behalf of American Institute of Biological Sciences 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US. The published ...

  Citation × Citation Citation Abstract Copy Title: Flow Management for Hydropower Extirpates Aquatic Insects, Undermining River Food Webs Author: Lytle, David A., Baxter, Colden V., Muehlbauer, Jeffrey D., Kortenhoeven, Eric W., Yackulic, Charles B., Metcalfe, Anya N., Miller, Scott W., Dibble, Kimberly L., Kennedy, Theodore A. Published by Oxford University Press on behalf of American Institute of Biological Sciences 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US. The published article can be found at: http://bioscience.oxfordjournals.org/content/66/7/561 Title: Flow Management for Hydropower Extirpates Aquatic Insects, Undermining River Food Webs Author: Lytle, David A., Baxter, Colden V., Muehlbauer, Jeffrey D., Kortenhoeven, Eric W., Yackulic, Charles B., Metcalfe, Anya N., Miller, Scott W., Dibble, Kimberly L., Kennedy, Theodore A. Published by Oxford University Press on behalf of American Institute of Biological Sciences 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US. The published article can be found at: http://bioscience.oxfordjournals.org/content/66/7/561 Close

• 4. [Article] KennedyFlowManagementHydropower.pdf

  Citation × Citation Citation Abstract Copy Title: KennedyFlowManagementHydropower.pdf Author: Lytle, David A., Baxter, Colden V., Muehlbauer, Jeffrey D., Kortenhoeven, Eric W., Kennedy, Theodore A., Metcalfe, Anya N., Miller, Scott W., Dibble, Kimberly L., Yackulic, Charles B. Title: KennedyFlowManagementHydropower.pdf Author: Lytle, David A., Baxter, Colden V., Muehlbauer, Jeffrey D., Kortenhoeven, Eric W., Kennedy, Theodore A., Metcalfe, Anya N., Miller, Scott W., Dibble, Kimberly L., Yackulic, Charles B. Close

• 5. [Article] KennedyFlowManagementHydropowerSupplement.pdf

  Citation × Citation Citation Abstract Copy Title: KennedyFlowManagementHydropowerSupplement.pdf Author: Lytle, David A., Baxter, Colden V., Muehlbauer, Jeffrey D., Kortenhoeven, Eric W., Kennedy, Theodore A., Metcalfe, Anya N., Miller, Scott W., Dibble, Kimberly L., Yackulic, Charles B. Title: KennedyFlowManagementHydropowerSupplement.pdf Author: Lytle, David A., Baxter, Colden V., Muehlbauer, Jeffrey D., Kortenhoeven, Eric W., Kennedy, Theodore A., Metcalfe, Anya N., Miller, Scott W., Dibble, Kimberly L., Yackulic, Charles B. Close

• 6. [Article] Biophysical, Socioeconomic, and Geopolitical Vulnerabilities to Hydropower Development on the Nu River, China

  This is the publisher’s final pdf. The published article is copyrighted by Resilience Alliance and can be found at: http://www.resalliance.org/.

  Citation × Citation Citation Abstract Copy Title: Biophysical, Socioeconomic, and Geopolitical Vulnerabilities to Hydropower Development on the Nu River, China Author: Tilt, Bryan, Gassert, Francis, Schmitt, Edwin, Foster-Moore, Eric, Kibler, Kelly, Magee, Darrin, Tullos, Desiree D., Wolf, Aaron T. This is the publisher’s final pdf. The published article is copyrighted by Resilience Alliance and can be found at: http://www.resalliance.org/. Title: Biophysical, Socioeconomic, and Geopolitical Vulnerabilities to Hydropower Development on the Nu River, China Author: Tilt, Bryan, Gassert, Francis, Schmitt, Edwin, Foster-Moore, Eric, Kibler, Kelly, Magee, Darrin, Tullos, Desiree D., Wolf, Aaron T. This is the publisher’s final pdf. The published article is copyrighted by Resilience Alliance and can be found at: http://www.resalliance.org/. Close