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Evaluating Flow Metric-Based Stream Classification Systems to Support the Determination of Ecological Flows in North Carolina

Streamflow is a main determinant of the ecological health of rivers and streams. Assignment of streams to classes is suggested as an initial step in the process of establishing ecological flow standards that ensure the appropriate environmental objectives are achieved. A new article in the Journal of the American Water Resources Association evaluated a hydrological model with two distinct hydroecological river classification systems of stream classes in North Carolina and found that stream classification was inconsistent between all three models and highly dependent on the period of record of the underlying data. Based on these results, it was surmised that classification systems based on streamflow metrics are not a reliable approach for guiding ecological flow determinations.

Authors: Michele C. Eddy, Jennifer Phelan, Lauren Patterson, Jessie Allen and Sam Pearsal

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Water Policy

State Policy

Journal Articles

Fish and Invertebrate Flow-Biology Relationships to Support the Determination of Ecological Flows for North Carolina

Following recent droughts in North Carolina, the General Assembly convened an Ecological Flows Science Advisory Board to develop a strategy for establishing flow regimes that could protect the ecological integrity in the streams and rivers of North Carolina. A new article in the Journal of the American Water Resources Association describes the method developed to characterize fish and invertebrate responses to flow alterations in the state of North Carolina to aid in setting ecologically sensitive flows that achieve appropriate environmental objectives.

Authors: Jennifer Phelan, Tom Cuffney, Lauren Patterson, Michele Eddy, Robert Dykes, Sam Pearsall, Chris Goudreau, Jim Mead and Fred Tarver

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Water Policy

State Policy

Journal Articles

Flow-Biology Relationships Based on Fish Habitat Guilds in North Carolina

The health of freshwater animal and plant life is dependent on streamflow, yet identification of the flow regimes required to maintain ecological integrity remains challenging to states in the U.S. seeking to establish ecological flows that achieve environmental objectives. A new article in the Journal of the American Water Resources Association tests the relationship between decreases in streamflow and Shannon-Weaver diversity index of fish species for four flow-based habitat guilds: riffle, riffle-run, pool-run, and pool in North Carolina. The study finds that species who prefer shallow habitats, such as riffles and riffle-runs were the most sensitive to decreases in streamflow, while using all fish data greatly underestimated the response of fish species to decreases in flow. Since ecological flows are designed to protect the integrity and diversity of aquatic ecosystems, ecological flows should be established to protect those species most sensitive to changes in flow.

Authors: Lauren Patterson, Jennifer Phelan, Chris Goudreau and Robert Dykes

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Water Policy

State Policy

Journal Articles

The Uncertain Future of Nuclear Power in the Southeast: Implications of an Aging Fleet for Electricity Sector Planning and Emissions

Nuclear power provides about one-quarter of the electricity in the Southeast and the majority of the region’s non-fossil generation. Beginning around 2030, nuclear plants in the Southeast, as in the rest of the country, will start to reach the end of their initial operating license extensions to 60 years, at which point they must receive an additional license extension or retire. How many nuclear units will seek and receive a second license extension is unknown. Replacing existing nuclear capacity with new nuclear capacity requires approximately 10 to 15 years. If a high percentage of nuclear units in the Southeast do retire at 60 years, it is unlikely that the units can simultaneously be replaced with new units given the long lead times and limited applications for new nuclear plants at the Nuclear Regulatory Commission. Given these circumstances, southeastern states may want to start planning for the potential loss of their largest carbon-free generation source now. This policy brief explores how the potential loss of existing nuclear power plants in the Southeast interacts with region’s other electricity sector challenges—among them, increasing natural gas dependence, demand uncertainty, and emerging technology—and it proposes steps states can take to address these challenges.

Authors: David Hoppock and Sarah Adair

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Climate and Energy

Environmental Economics

Energy Sector

Policy Briefs

Unconventional Oil and Gas Spills: Materials, Volumes, and Risks to Surface Waters in Four States of the U.S.

A new article in the journal Science of the Total Environment examines spill data associated with unconventional oil and gas wells from Colorado, New Mexico, North Dakota, and Pennsylvania from 2005 to 2014. The authors used the data to evaluate the environmental risk of spills. They found that there were 21,300 unconventional wells and 6,622 reported spills. Across all states, the average distance of spills to a stream was highest in New Mexico, followed by Colorado, North Dakota, and Pennsylvania. Pennsylvania spills occurred in watersheds with a higher relative importance to drinking water than the other three states.

Authors: Kelly O. Maloney, Sharon Baruch-Mordo, Lauren A. Patterson, Jean-Philippe Nicot, Sally A. Entrekin, Joseph E. Fargione, Joseph M. Kiesecker, Kate E. Konschnik, Joseph N. Ryan, Anne M. Trainor, James E. Saiers, and Hannah J. Wiseman

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Hydraulic Fracturing and Water Use

Water Policy

State Policy

Journal Articles

Revisiting the NAAQS Program for Regulating Greenhouse Gas Emissions under the Clean Air Act

The future is uncertain for the regulation of greenhouse gases from power plants, including the U.S. Environmental Protection Agency’s (EPA) Clean Power Plan, which covers existing plants. The rule is under review in the D.C. Circuit Court of Appeals, and the Supreme Court has indicated its interest in hearing the case. Moreover, during his presidential campaign, president-elect Donald Trump promised to “scrap” the Clean Power Plan. If the rule is overturned or is severely weakened, whether through litigation or executive action, stakeholders are likely to litigate to seek to force the EPA to use other authorities under the Clean Air Act to regulate greenhouse gas emissions.

This working paper examines the opportunities and challenges associated with regulation of greenhouse gases under the National Ambient Air Quality Standards (NAAQS) program, drawing a comparison with the Clean Power Plan’s approach under a different section of the Clean Air Act. The paper offers no opinion on the Clean Power Plan litigation, nor does it advocate for the Clean Power Plan or the NAAQS approach. Its focus is on understanding how the NAAQS program might incorporate greenhouse gases in in the event that the EPA pursues that approach.

Authors: Christina Reichert, Franz Litz, Jonas Monast, Tim Profeta, and Sarah Adair

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Climate and Energy

Clean Air Act

Environmental Economics

State Policy

Working Papers

The Challenge of Decarbonizing the U.S. Power Sector: Encouraging Innovation and Aligning Stakeholder Interests

Recent interest in and commitments to reduce greenhouse gas (GHG) emissions will require significant reductions of carbon dioxide (CO2) emissions from the U.S. power sector. Those reductions will in turn require a transformation in how electricity is produced, distributed, and consumed—a transformation possible only with intensive collaboration at all community scales, from local to state, regional, and national, and with attention to public, private, and government interests. Today’s decisions about this national investment will affect ratepayers, the environment, and the economy for many decades, making transparency, participation, and technical, financial, and regulatory coordination crucial to optimize benefits and minimize costs. This working paper describes current U.S. power sector trends and relevant environmental goals, ways that technology innovation could proceed or be interrupted, and three emerging low- and zero-carbon technologies generally considered leading options for meeting the decarbonization challenge. It concludes with ideas from a range of experts to meet GHG reduction goals and accelerate innovation to advance low-carbon generation. These ideas illustrate different perspectives on possible steps forward as well as the need for a venue or process for multiple stakeholders and experts involved in advanced energy technology, policy, investment, and implementation to collaborate in evaluating and prioritizing investments, policies, and broad efforts.

Authors: Etan Gumerman, Michelle Bergin, Jesse Way, Julie DeMeester, and Kerri Metz

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Climate and Energy

Environmental Economics

Energy Sector

Working Papers

Data and Modeling Infrastructure for National Integration of Ecosystem Services into Decision Making: Expert Summaries

Resource managers face increasingly complex decisions as they attempt to manage for the long-term sustainability and the health of natural resources. Incorporating ecosystem services into decision processes provides a means for increasing public engagement and generating more transparent consideration of tradeoffs that may help to garner participation and buy-in from communities and avoid unintended consequences. A 2015 White House memorandum from the Council on Environmental Quality, Office of Management and Budget, and Office of Science Technology and Policy acknowledged these benefits and asked all federal agencies to incorporate ecosystem services into their decision making. This working paper describes the ecological and social data and models available for quantifying the production and value of many ecosystem services across the United States. To achieve nationwide inclusion of ecosystem services, federal agencies will need to continue to build out and provide support for this essential informational infrastructure.

Authors: Lydia Olander, Gregory W. Characklis, Patrick Comer, Micah Effron, John Gunn, Tom Holmes, Robert Johnston, James Kagan, William Lehman, John Loomis, Timon McPhearson, Anne Neale, Lauren Patterson, Leslie Richardson, Martin Ross, David Saah, Samantha Sifleet, Keith Stockmann, Dean Urban, Lisa Wainger, Robert Winthrop, and David Yoskowitz

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Ecosystem Services

National Ecosystem Services Partnership

Working Papers

Proposal for Increasing Consistency When Incorporating Ecosystem Services into Decision Making

In October 2015, the U.S. Executive Offices of the President—the Office of Management and Budget, the Council on Environmental Quality, and the Office of Science and Technology Policy—released a memo, “Incorporating Ecosystem Services into Federal Decision Making,” that directed federal agencies to develop work plans and implementation guidance by the end of 2016. But many practical questions remain about how ecosystem services can most effectively be used in decision making. This policy brief explores how to achieve consistency in the use of ecosystem services, primarily in terms of which ecosystem services are selected for assessment and how they are quantified. An initial idea for promoting consistency might be to require all decision makers to consider a common set of ecosystem services, each with a pre-defined metric. Although this strategy might seem logical, it may not provide relevant or useful information for decision makers because even fairly constrained categories of these services—say those for maintaining air and water quality, managing water quantity, and reducing risks from fire, storms, and droughts—when further refined break up into many more services that are defined by who is affected and how they are affected. For example, a water quality management issue results in a change in water quality for downstream stakeholders—which can alter services such as municipal water supplies, irrigation, fishing, swimming, and so on. Each of these services involves different stakeholder populations or beneficiaries. Moreover, each of these services might be more or less relevant in different contexts or regions. The ecosystem services that should be considered in a particular decision depend on the ecosystem type, the attributes and qualities of that ecosystem, the ways in which surrounding human communities use or appreciate the ecosystem, vulnerabilities and characteristics of those communities, and the preferences and values of human beneficiaries in different areas and policy contexts. They also depend on the temporal and spatial scale of the project, plan, program, or policy under consideration. Consequently, achieving consistency in the selection of ecosystem services to be considered is a complex task, as is achieving consistency in quantification of those services across decision contexts.

Authors: Lydia Olander, Dean Urban, Robert J. Johnston, George Van Houtven, and James Kagan

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Ecosystem Services

National Ecosystem Services Partnership

Policy Briefs

Conservation Finance and Impact Investing for U.S. Water

The 2016 Aspen-Nicholas Water Forum focused on the shifting role of public and private financing for water infrastructure and the new universe of innovative financing solutions to create impacts in the water sector, including how impact investing can hold the multiple roles of bridging the ever growing funding gap for infrastructure, improve water use efficiencies, and protect water resources while at the same time making a financial profit. Among the forum report's key findings: 1) Business as usual is not sustainable—we as a society are now paying for the “can-kicking” that has occurred while we debated responsibility for U.S. water resources; 2) The water issues we face as a nation continue to grow as the water community dithers and invests in one-off projects, rather than focusing on scaled solutions like regionalization and integration; 3) Money is not the issue; there is plenty of private capital available to meet the current water funding gap, but there are significant barriers to impactful and innovative financing; 4) Government regulation and public education can go hand in hand to gain public support for improved water management while supporting social equity; and 5) Leadership is one of the prime movers for innovative finance projects in the water space.

Authors: Lauren Patterson, Martin Doyle, and Nicole Buckley

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Aspen-Nicholas Institute Water Forum

Water Policy

Environmental Economics

Reports

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