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A framework for modeling anthropogenic impacts on waterbird habitats: addressing future uncertainty in conservation planning

The amount and quality of natural resources available for terrestrial and aquatic wildlife habitats are expected to decrease throughout the world in areas that are intensively managed for urban and agricultural uses. Changes in climate and management of increasingly limited water supplies may further impact water resources essential for sustaining habitats. In this report, we document adapting a Water Evaluation and Planning (WEAP) system model for the Central Valley of California. We demonstrate using this adapted model (WEAP-CV wh ) to evaluate impacts produced from plausible future scenarios on agricultural and wetland habitats used by waterbirds and other wildlife. Processed output from WEAP-CV wh indicated varying levels of impact caused by projected climate, urbanization, and water supply management in scenarios used to exemplify this approach. Among scenarios, the NCAR-CCSM3 A2 climate projection had a greater impact than the CNRM-CM3 B1 climate projection, whereas expansive urbanization had a greater impact than strategic urbanization, on annual availability of waterbird habitat. Scenarios including extensive rice-idling or substantial instream flow requirements on important water supply sources produced large impacts on annual availability of waterbird habitat. In the year corresponding with the greatest habitat reduction for each scenario, the scenario including instream flow requirements resulted in the greatest decrease in habitats throughout all months of the wintering period relative to other scenarios. This approach provides a new and useful tool for habitat conservation planning in the Central Valley and a model to guide similar research investigations aiming to inform conservation, management, and restoration of important wildlife habitats.

California↗

Hydrology, water quality, and phosphorus loading of Little St. Germain Lake, Vilas County, Wisconsin

Little St. Germain Lake, which is in Vilas County. Wisconsin, just northeast of St. Germain (fig. 1), is one of 21 impoundments operated by Wisconsin Valley Improvement Company (WVIC) to provide storage for power and recreational use. The level of the lake, which was originally dammed in 1882, has been maintained by the WVIC at about 5 feet above its natural level since 1929, and it is annually drawn down about 1.5 feet from December through March. In the interest of protecting and improving the water quality of the lake, the Little St. Germain Lake Improvement Association was established in 1959. Later, the I .ittle St. Germain Lake District was formed. The Wisconsin Department of Natural Resources (WDNR), in collaboration with the Lake District, did a study during 1983-85 to document the water quality of the lake and examine management alternatives (Wisconsin Department of Natural Resources, 1985). Results of the study indicated that, because of relatively high phosphorus loading to the lake, most of the lake was eutrophic (relatively productive), with the possible exception of the West Bay. The results also indicated monitoring of the lake should continue, and that actions should be taken to decrease nutrient loading to the lake by controlling erosion, fertilizer runoff, and leakage from septic systems. The lake was monitored in detail again during 1991-94 by the U.S. Geological Survey (USGS) as part of a cooperative study with the Lake District. This study demonstrated water-quality variation among the basins of Little St. Germain Lake and extensive areas of winter anoxia (absence of oxygen). Further in-depth studies were then conducted during 1994-2000 to define the extent of winter anoxia, refine the hydrologic and phosphorus budgets of the lake, quantify the effects of annual drawdowns, and provide information needed to develop a comprehensive lake-management plan. This report presents the results of the studies since 1991.

Wisconsin↗

Quantification of transit losses, and its effects on surface-water resources, Arkansas River basin, Colorado

Colorado Water Law enables downstream water users to use natural river channels to convey water from upstream storage reservoirs to downstream canals, provided an equitable charge is made for transit loss. Charging a variable transit-loss rate for delivery of winter water stored in Pueblo Reservoir has resulted in better management of the basin's surface-water resources. Not only are more accurate volumes of stored water delivered to each irrigator, but use of the natural channel for conveyance of these waters now has minimal effect on users of direct-flow water rights. A better understanding of specific sources of transit loss also has allowed water users to manage the timing and rate of their reservoir releases to optimize beneficial use of their stored water.

Colorado↗

The potential effects of sodium bicarbonate, a major constituent from coalbed natural gas production, on aquatic life

The production water from coalbed natural gas (CBNG) extraction contains many constituents. The U.S. Environmental Protection Agency has established aquatic life criteria for some of these constituents, and it is therefore possible to evaluate their risk to aquatic life. However, of the major ions associated with produced waters, chloride is the only one with an established aquatic life criterion (U.S. Environmental Protection Agency, 1988). The focus of this research was NaHCO 3 , a compound that is a major constituent of coalbed natural gas produced waters in the Tongue and Powder River Basins. This project included laboratory experiments, field in situ experiments, a field mixing zone study, and a fishery presence/absence assessment. Though this investigation focuses on the Tongue and Powder River Basins, the information is applicable to other watersheds where sodium bicarbonate is a principle component of product water either from CBNG or from traditional or unconventional oil and gas development. These data can also be used to separate effects of saline discharges from those potentially posed by other constituents. Finally, this research effort and the additional collaboration with USGS Water Resources and Mapping, Bureau of Land Management, US Environmental Protection Agency, State of Montana, State of Wyoming, Montana State University, University of Wyoming, and others as part of a Powder River Aquatic Task Group, can be used as a model for successful approaches to studying landscapes with energy development. The laboratory acute toxicity experiments were completed with a suite of organisms, including 7 species of fish, 5 species of invertebrates, and 1 amphibian species. Experiments performed on these multiple species resulted in LC50s that ranged from 1,120 to greater than (>) 8,000 milligrams sodium bicarbonate per liter (mg NaHCO 3 /L) (also defined as 769 to >8,000 milligrams bicarbonate per liter (mg HCO 3 -/L) or total alkalinity expressed as 608 to >4,181 milligrams calcium carbonate per liter (mg CaCO 3 /L)) that varied across species and lifestage within a species. The age at which fish were exposed to NaHCO 3 significantly affected the severity of toxic responses for some organisms. The chronic toxicity of NaHCO 3 was defined in experiments that lasted from 7—60 days post-hatch. For these experiments, sublethal effects such as growth and reproduction, in addition to significant reductions in survival were included in the final determination of effects. Chronic toxicity was observed at concentrations that ranged from 450 to 800mg NaHCO 3 /L (also defined as 430 to 657 mg HCO 3 -/L or total alkalinity expressed as 354 to 539 mg CaCO 3 /L) and the specific concentration depended on the sensitivity of the four species of invertebrates and fish exposed. Sublethal investigations during chronic studies revealed percent decrease in the activity of sodium-potassium adenosine triphosphatase (Na/K ATPase, an enzyme involved in ionoregulation) and the age of the fish at the onset of the decrease may affect the ability of fathead minnow to survive exposures to NaHCO 3 . A database of toxicity evaluations of NaHCO 3 on aquatic life has been constructed. Using these data, sample acute and chronic criteria of 459 and 381 mg NaHCO 3 /L, respectively, can be calculated for the protection of aquatic life. The final derivation and implementation of such criteria is, of course, left to the discretion of the concerned management agencies. A combination of in situ experiments, static-renewal experiments performed simultaneously with in situ experiments, and static renewal experiments performed with site water in the laboratory, demonstrated that untreated coalbed natural gas (CBNG) product water from the Tongue and Powder River Basins reduces survival of fathead minnow and pallid sturgeon. More precisely, the survival of early-lifestage fathead minnow, especially those less than 6-days post hatch (dph), likely is reduced significantly in the field when concentrations of NaHCO 3 rise above 1,500 mg/L. However, age was not a factor for pallid sturgeon and they were sensitive to product water regardless of age. Treatment with the Higgins Loop™ technology and dilution of untreated water increased survival in the laboratory. Both of these situations reduced ammonia in addition to the concentrations of NaHCO 3 . These experiments addressed the acute toxicity of effluent waters being added to the main stem rivers, but did not address issues related to the volumes of water that may be added to the watershed. Mixing zones of the three outfalls studied ranged from approximately 800—1,200 m below the confluence and the areas within these mixing zones with acutely lethal concentrations of NaHCO 3 (as defined by the presence of concentrated dye) are limited. The areas with concentrations of NaHCO 3 more than the concentrations likely to cause significant mortality, and more than the calculated sample water-quality criteria in the Tongue and Powder River Basins appear to be limited to tributaries and parts of mixing zones with considerable additions of untreated effluent.

Montana;Wyoming↗

A policy model to initiate environmental negotiations: Three hydropower workshops

How do I get started in natural resource negotiations? Natural resource managers often face difficult negotiations when they implement laws and policies regulating such resources as water, wildlife, wetlands, endangered species, and recreation. As a result of these negotiations, managers must establish rules, grant permits, or create management plans. The Legal‐Institutional Analysis Model (LIAM) was designed to assist managers in systematically analyzing the parties in natural resource negotiations and using that analysis to prepare for bargaining. The LIAM relies on the theory that organizations consistently employ behavioral roles. The model uses those roles to predict likely negotiation behavior. One practical use of the LIAM is when all parties to a negotiation conduct a workshop as a way to open the bargaining on a note of trust and mutual understanding. The process and results of three LIAM workshops designed to guide hydroelectric power licensing negotiations are presented. Our experience with these workshops led us to conclude that the LIAM can be an effective tool to begin a negotiation and that trust built through the workshops can help create a successful result.

Human Dimensions of Wildlife: An International Jou↗

Porphyry copper assessment of British Columbia and Yukon Territory, Canada: Chapter C in Global mineral resource assessment

The U.S. Geological Survey does regional, national, and global assessments of resources (mineral, energy, water, biologic) to provide science in support of land management and decision making. Mineral resource assessments provide a synthesis of available information about where mineral deposits are known and suspected to be in the Earth’s crust, which commodities may be present, and estimates of amounts of resources that may be present in undiscovered deposits. Canada is an important source of copper, consistently ranking as one of the top 10 world producers during the past decade (2000–2010). The preponderance of this production has been from porphyry-copper-type deposits in the western Canadian Cordillera. A probabilistic mineral resource assessment of undiscovered resources associated with porphyry copper deposits in western Canada was completed as part of a global mineral resource assessment. The purpose of the assessment was to (1) compile a database of known deposits and significant prospects, (2) delineate permissive areas (tracts) for undiscovered porphyry copper deposits that may be present in the upper kilometer (minimally) of the Earth’s crust, and (3) provide probabilistic estimates of amounts of copper (Cu), molybdenum (Mo), gold (Au), and silver (Ag) that could be contained in undiscovered porphyry copper deposits in the tracts. The study was done by the U.S. Geological Survey (USGS) in collaboration with geologists from the British Columbia Geological Survey, Yukon Geological Survey, and industry consultants. The database of known deposits and significant prospects includes an inventory of mineral resources in 89 known porphyry copper (and 2 related copper-bearing polymetallic vein) ore zones, representing 50 porphyry copper deposits, and lists key characteristics of 280 additional porphyry copper and related copper-bearing prospects, as indicated by currently available exploration results, which also are summarized. Resource and exploration and development activity are updated with information current through April 2010. The delineation of permissive tracts and probabilistic estimation of resources in undiscovered deposits were done using the USGS three-part mineral resource assessment approach. Permissive tracts are defined in accordance with descriptive models for porphyry copper deposits to include igneous rocks and known deposits and prospects within magmatic arcs related to convergent plate-margin boundary zones. Frequency distributions of total tonnages and average grades of thoroughly explored deposits were used as models for undiscovered deposits and include a new grade and tonnage model for calc-alkaline porphyry Cu±Mo±Au deposits in western Canada. Five permissive tracts for the occurrence of porphyry copper deposits were delineated: 2 island-arc tracts, 1 tract of transitional, mixed island-arc and continental arc affinities, and 2 continental arc tracts. In permissive tract 003pCu2001, calc-alkaline igneous rocks of Middle Triassic to Late Jurassic age in accreted island-arc terranes of the Intermontane belt are assessed for calc-alkaline porphyry Cu±Mo±Au deposits. The area of this tract is 175,250 km 2 . In 12 known deposits, the total reported tonnage of ore is 8,100 million metric tons (Mt) containing 24.6 Mt copper. An estimated 6.9 undiscovered deposits contain a calculated mean of 8.9 Mt copper and a median of 6.9 Mt copper. The spatial density for the 18.9 known plus estimated undiscovered deposits in this tract is approximately 11 deposits per 100,000 km 2 . In permissive tract 003pCu2002, alkaline igneous rocks of Middle Triassic to Late Jurassic age within the Intermontane accreted island-arc terranes are assessed for alkaline porphyry Cu-Au deposits. The area of this tract is 109,290 km 2 . In 12 known deposits the total reported tonnage of ore is 6,440 Mt, containing 20.9 Mt copper. An estimated 7 undiscovered deposits contain a calculated mean of 22 Mt copper and a median of 13 Mt copper. The spatial density for the 19 known plus estimated undiscovered deposits in this tract is approximately 17 deposits per 100,000 km 2 . In permissive tract 003pCu2003, calc-alkaline igneous rocks of Late Triassic to Early Cretaceous age within the accreted Insular terranes of mixed island-arc and continental arc affinities are assessed for calc-alkaline porphyry Cu±Mo±Au deposits. The area of this tract is 58,360 km 2 . The total tonnage of ore reported in the 2 known deposits is 1,160 Mt containing 3.17 Mt copper. An estimated 2.3 undiscovered deposits contain a calculated mean of 3 Mt copper and a median of 1.9 Mt copper. The spatial density for the 4.3 known plus estimated undiscovered deposits in this tract is approximately 7 deposits per 100,000 km 2 . In permissive tract 003pCu2004, calc-alkaline igneous rocks in continental magmatic arcs of Jurassic to Eocene age are assessed for porphyry Cu±Mo±Au deposits. The area of this tract is 639,500 km 2 . The total tonnage of ore reported for the 23 known deposits is 6,520 Mt containing 17.9 Mt copper. An estimated 9.6 undiscovered deposits contain a calculated mean of 13 Mt copper and a median of 11 Mt copper. The spatial density for the 32.6 known deposits plus the estimated undiscovered deposits in this tract is approximately 5 deposits per 100,000 km 2 . In permissive tract 003pCu2005, calc-alkaline igneous rocks in continental magmatic arcs of Oligocene to Pliocene age are assessed for porphyry Cu±Mo±Au deposits. The area of this tract is 32,840 km 2 . The total tonnage of ore reported for the 1 known deposit is 44.8 Mt containing 0.224 Mt copper. An estimated 1.4 undiscovered deposits contain a calculated mean of 1.8 Mt copper and a median of 0.72 Mt copper. The spatial density for the 2.4 known plus estimated undiscovered deposits in this permissive tract is approximately 7 deposits per 100,000 km 2 . Western Canada has been thoroughly explored for porphyry copper deposits. The total estimated copper contained in known deposits is about 66.8 Mt (based on 2010 data), as compared to a 49 Mt mean of estimated copper in undiscovered deposits and a 34 Mt median of estimated copper in undiscovered deposits. The copper contained in known porphyry copper deposits represents about 58 percent of the total of known and undiscovered porphyry copper deposits (based on mean values). About 86 percent of the increase in estimated copper resources between 1993 and 2009 resulted from the discovery of extensions to known deposits. Nevertheless, exploration for undiscovered deposits continues, especially in and around significant prospects and in parts of permissive tracts that are mostly hidden beneath younger volcanic, sedimentary, or vegetated surficial cover.

British Columbia, Yukon Territory↗

The water-energy nexus: An earth science perspective

Water availability and use are closely connected with energy development and use. Water cannot be delivered to homes, businesses, and industries without energy, and most forms of energy development require large amounts of water. The United States faces two significant and sometimes competing challenges: to provide sustainable supplies of freshwater for humans and ecosystems and to ensure adequate sources of energy for future generations. This report reviews the complex ways in which water and energy are interconnected and describes the earth science data collection and research that can help the Nation address these important challenges. The earth sciences have been a cornerstone in developing our current understanding of the water-energy nexus. A full understanding of the nexus, however, is limited by uncertainty in our knowledge of fundamental issues, such as the quantity of freshwater that is available, the amount of water that is used in energy development, the effects that emerging energy development technologies have on water quality and quantity, and the amount of energy required to treat and deliver freshwater. Enhanced data collection and research can improve our understanding of these important issues and thereby lay the groundwork for informed resource management. Relevant earth science issues analyzed and discussed herein include freshwater availability; water use; ecosystems health; assessment of saline water resources; assessment of fossil-fuel, uranium, and geothermal resources; subsurface injection of wastewater and carbon dioxide and related induced seismicity; climate change and its effect on water availability and energy production; byproducts and waste streams of energy development; emerging energy-development technologies; and energy for water treatment and delivery.

Circular↗

Second Integrated Hydro-Terrestrial Modeling (IHTM 2.0) workshop: USGCRP federal agency perspectives

U.S. federal leadership, mobilizing close interagency coordination across sectors, is key to tackling compound climate and human impacts on our nation’s water resources. Recognizing this need, federal agencies and academic collaborators conducted a series of workshops to advance Integrated Hydro-Terrestrial Modeling (IHTM). IHTM is focused on supporting a multiscale framework to accelerate research insights, better integrate operational and planning perspectives, and bridge national-to-regional capabilities to address major interdependent societal water challenges. This framework leverages the capabilities of different agencies and institutional partners across sectors to advance a shared vision for use-inspired modeling and open science. The IHTM conceptual framework has developed over several community workshops in recent years: ● In September 2019, a community coordinating group on IHTM hosted an interagency workshop (“IHTM 1.0”) with support from NSF, DOE, and USGS. The resulting report identified the need for agencies to invest resources in designing pilot use cases, setting the stage for an integrated national IHTM capability. ● In November 2020, the U.S. Global Change Research Program (USGCRP) held a virtual Coastal-IHTM (C-IHTM) workshop in collaboration with the MultiSector Dynamics Community of Practice, which engages researchers across universities and national labs. Building on IHTM 1.0, this workshop aimed to identify coastal modeling capabilities and appropriate coastal applications of the IHTM framework. The workshop report detailed needs for open science, geographical or topical use cases, integrated modeling frameworks, and linking communities of practice. ● From October 31 to November 2, 2023, USGCRP hosted a hybrid IHTM 2.0 community workshop that brought together 160 scientists and managers from nine federal departments/agencies (DHS-FEMA, DOC-NOAA, DoD-USACE, DOE, DOI [U.S. Bureau of Reclamation (USBR), USGS], EPA, NASA, NSF, USDA [ARS, FS, NRCS]) and 32 non-federal academic, non-profit, and private institutions and consortiums. The workshop was organized by a federal Interagency Steering Committee with representatives from DOE, USGS, NSF, NASA, and NOAA, as well as a Scientific Organizing Committee comprising experts from academia and additional federal agency technical experts. The IHTM 2.0 workshop focused on moving the IHTM 1.0 concepts to action by making advances in designing national and regional integrated modeling experiments in five geographic testbeds. These modeling testbeds seek to facilitate collaborative water resources research and assessment that responds to societal needs, extending from basic research to resource management operations, including the assessment of water quantity, quality, and use at national and regional scales. Ultimately, we envision that the IHTM testbeds will improve our ability to provide water resources assessment scenarios to decision-makers and the public. This document summarizes USGCRP and member agencies’ perspectives of the IHTM 2.0 workshop. Sections 2 and 3 build on the work of the IHTM 2.0 workshop Scientific Organizing Committee to outline the importance of IHTM, summarize the workshop, and propose near- and medium-term IHTM priorities. Section 4 presents select ongoing and potential interagency activities that could help realize the IHTM 2.0 vision and align with three of USGCRP’s strategic goals for this decade: Advancing Science, Informing Decisions, and Engaging the Nation. Finally, Section 5 summarizes this report and offers information about how to connect with USGCRP’s IHTM activities. USGCRP and its member agencies are well-positioned to coordinate federal efforts to enhance IHTM capabilities in the coming years.

Conference Paper↗

Network analysis of a regional fishery: Implications for management of natural resources, and recruitment and retention of anglers

Angler groups and water-body types interact to create a complex social-ecological system. Network analysis could inform detailed mechanistic models on, and provide managers better information about, basic patterns of fishing activity. Differences in behavior and reservoir selection among angler groups in a regional fishery, the Salt Valley fishery in southeastern Nebraska, USA, were assessed using a combination of cluster and network analyses. The four angler groups assessed ranged from less active, unskilled anglers (group One) to highly active, very skilled anglers (group Four). Reservoir use patterns and the resulting network communities of these four angler groups differed; the number of reservoir communities for these groups ranged from two to three and appeared to be driven by reservoir location (group One), reservoir size and its associated attributes (groups Two and Four), or an interaction between reservoir size and location (group Three). Network analysis is a useful tool to describe differences in participation among angler groups within a regional fishery, and provides new insights about possible recruitment of anglers. For example, group One anglers fished reservoirs closer to home and had a greater probability of dropping out if local reservoir access were restricted.

Fisheries Research↗

Fifteen years of WRTDS for advancing water-quality science: A critical review of methodological developments and global applications

Contamination by nutrients, major ions, and metals poses a major threat to global water sustainability. Understanding how these pollutants vary across time and space requires long-term monitoring and robust statistical approaches. Traditional methods, however, often struggle to account for streamflow variability, seasonality, and nonlinear responses. Introduced in 2010, the Weighted Regressions on Time, Discharge, and Season (WRTDS) method offers a flexible, data-driven framework that generates both observed and flow-normalized estimates of concentration and load. Over the past 15 years, WRTDS has become a state-of-the-art tool for water-quality science and management, with applications spanning a wide range of hydrologic, climatic, and policy contexts─including major watersheds across North America, Europe, Asia, Australia, and the Arctic. In this review of WRTDS, we document the method’s major advancements, examine its expanding geographic and thematic applications, and summarize its relevance to water-quality management programs and policies worldwide. We also discuss its performance relative to other regression and machine-learning approaches. Finally, we identify key priorities for future development to support the continued evolution of WRTDS as a trusted and practical tool for scientists and managers working to protect and sustain water resources.

Environmental Science and Technology↗

National Water‐Use Information Program

The US National Water-Use Information Program is a cooperative program between the states and the Federal Government. The purpose of the program is to determine how much fresh and saline surface water and ground water is withdrawn and for what purpose, how much water is consumed during use, and how much water is returned to a water body after use. To accomplish its purpose, the program's goals are to: 1) collect and compile water-use data; 2) develop and refine computerized water-use data systems; 3) improve the collection and analysis of water-use information; and 4) disseminate information.-from ASCE Publications Information

Journal of Water Resources Planning and Management↗

A uniform technique for flood frequency analysis.

This uniform technique consisted of fitting the logarithms of annual peak discharges to a Pearson Type III distribution using the method of moments. The objective was to adopt a consistent approach for the estimation of floodflow frequencies that could be used in computing average annual flood losses for project evaluation. In addition, a consistent approach was needed for defining equitable flood-hazard zones as part of the National Flood Insurance Program. -from ASCE Publications Information

Journal of Water Resources Planning and Management↗

Regression estimates for topological‐hydrograph input

Physiographic, hydrologic, and rainfall data from 18 small drainage basins in semiarid, central Wyoming were used to calibrate topological, unit‐hydrograph models for celerity, the average rate of travel of a flood wave through the basin. The data set consisted of basin characteristics and hydrologic data for the 18 basins and rainfall data for 68 storms. Calibrated values of celerity and peak discharges subsequently were regressed as a function of the basin characteristics and excess rainfall volume. Predicted values obtained in this way can be used as input for estimating hydrographs in ungaged basins. The regression models included ordinary least‐squares and seemingly unrelated regression. This latter regression model jointly estimated the celerity and peak discharge. The correlation between residuals of the celerity and peak‐discharge regressions was sufficiently large to de‐, crease the variances of estimated univariate‐model parameters.

Journal of Water Resources Planning and Management↗

Criteria for evaluating state instream-flow programs: Deciding what works

Most states have adopted some form of instream-flow–protection program. These programs are of three types: instream-flow water rights; reservations of water for instream purposes; and conditions on consumptive water rights. No matter which type of protection program is adapted, the same question remains: How can we tell if it works? Several authors have attempted to answer this question. The works of these analysts are reviewed and criteria are suggested to evaluate the success of an instream-flow–protection program. The criteria are public confidence, certainty, proper administration, expense, and outcome in-stream.

Journal of Water Resources Planning and Management↗

Support of total maximum daily load programs using spatially referenced regression models

The spatially referenced regressions on watershed attributes modeling approach, as applied to predictions of total nitrogen flux in three North Carolina river basins, addresses several information needs identified by a National Research Council evaluation of the total maximum daily load program. The model provides reach-level predictions of the probability of exceeding water-quality criteria, and estimates of total nitrogen budgets. Model estimates of point- and diffuse-source contributions and nitrogen loss rates in streams and reservoirs compared moderately well with literature estimates. Maps of reach-level predictions of nutrient inputs and delivery provide an intuitive and spatially detailed summary of the origins and fate of nutrients within a basin.

Journal of Water Resources Planning and Management↗

The Grand Ethiopian Renaissance Dam: Source of cooperation or contention?

This paper discusses the challenges and benefits of the Grand Ethiopian Renaissance Dam (GERD), which is under construction and expected to be operational on the Blue Nile River in Ethiopia in a few years. Like many large-scale projects on transboundary rivers, the GERD has been criticized for potentially jeopardizing downstream water security and livelihoods through upstream unilateral decision making. In spite of the contentious nature of the project, the authors argue that this project can provide substantial benefits for regional development. The GERD, like any major river infrastructure project, will undeniably bring about social, environmental, and economic change, and in this unique case has, on balance, the potential to achieve success on all fronts. It must be stressed, however, that strong partnerships between riparian countries are essential. National success is contingent on regional cooperation.

Journal of Water Resources Planning and Management↗