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A monthly water-balance model driven by a graphical user interface

This report describes a monthly water-balance model driven by a graphical user interface, referred to as the Thornthwaite monthly water-balance program. Computations of monthly water-balance components of the hydrologic cycle are made for a specified location. The program can be used as a research tool, an assessment tool, and a tool for classroom instruction.

Open-File Report↗

Living with wildfire in Santa Fe: 2021 Data Report

The City of Santa Fe is well known for arts, food, and architecture, but it also faces significant risk of wildfire. In 2020, the City of Santa Fe partnered with the Wildfire Research (WiRē) team with the goal of better understanding the needs of residents within the study area and their level of support for wildfire risk mitigation programs. The resulting project centers on two types of property-level data: rapid wildfire risk assessment data and household survey data. We followed the WiRē Rapid Wildfire Risk Assessment (WiRē RA) protocol, which measures parcel-level risk as the sum of a set of 13 attributes related to access to the property, background fuels and topography, vegetation near the home, and building materials. This report summarizes the results of the study. Overall, the study indicated a community that was engaged in preparing for wildfire yet had more that could be done to reduce its risk. Common architectural styles led to generally hardened structures, and respondents reported many risk reduction activities, yet most properties were found to have significant vulnerabilities related to limited defensible space and combustible materials near and attached to dwellings. Although many survey respondents did not perceive these same vulnerabilities on their own properties, survey results nonetheless demonstrated widespread interest for programs intended to reduce wildfire risk at the landscape, community, and individual parcel scales.

New Mexico↗

Ground motion and seismic hazard in the central and eastern United States

This report describes work carried out under the U.S. Nuclear Regulatory Commission (NRC) Interagency Agreement to the U.S. Geological Survey (USGS) “Research to Support NRC’s Seismic Hazard Analyses” for Task 3, “Seismic Hazard and Ground Motion Models.” The focus of this work has been on evaluation of the Next Generation Attenuation (NGA)-East groundmotion models (GMMs) with available ground-motion data and evaluation of alternative methods for characterizing epistemic uncertainty for probabilistic seismic hazard analysis (PSHA). When the Interagency Agreement commenced, the USGS’s National Seismic Hazard Model (NSHM) was being updated, and a significant part of the update for the 2018 NSHM included the introduction of new GMMs for the central and eastern United States (CEUS) (Petersen et al., 2020). In addition to the implementation of the then-recently developed NGA-East GMMs (Goulet et al., 2018), the ground-motion characterization for the CEUS in the 2018 NSHM also included a logic-tree branch with weights applied to the updated “adjusted seed” models that were developed as part of the NGA-East process and in updates by the GMM developers. The Statement of Work for Task 3 of the NRC Interagency Agreement to the USGS included the following parts: (1) Describe technically acceptable approaches in combining GMMs for use in PSHA calculations; (2) Evaluate the effect of using different sets of GMMs (NGA-East SSHAC versus NGA-East USGS) on PSHA calculations; (3) Describe the results of the GMM testing against recorded data, and provide a recommendation on the GMMs application for use in the PSHA; (4) Evaluate the impacts of recently updated individual GMMs on the published NGAEast models; and (5) Submit a final Technical Letter Report documenting results of this task. We present results from this work in two sections: (Chapter 1) Updated Central and Eastern United States Ground Motions and Ground-Motion Analyses; and (Chapter 2) Approaches to Combining Ground-Motion Models for Probabilistic Seismic Hazard Analysis in the Central and Eastern United States.

central and eastern United States↗

Selected papers in the applied computer sciences 1992

This compilation of short papers reports on technical advances in the applied computer sciences. The papers describe computer applications in support of earth science investigations and research. This is the third volume in the series "Selected Papers in the Applied Computer Sciences." Listed below are the topics addressed in the compilation: Integration of geographic information systems and expert systems for resource management, Visualization of topography using digital image processing, Development of a ground-water data base for the southeastern Uited States using a geographic information system, Integration and aggregation of stream-drainage data using a geographic information system, Procedures used in production of digital geologic coverage using compact disc read-only memory (CD-ROM) technology, and Automated methods for producing a technical publication on estimated water use in the United States.

Bulletin↗

Onshore industrial wind turbine locations for the United States

This dataset provides industrial-scale onshore wind turbine locations in the United States, corresponding facility information, and turbine technical specifications. The database has wind turbine records that have been collected, digitized, locationally verified, and internally quality controlled. Turbines from the Federal Aviation Administration Digital Obstacles File, through product release date July 22, 2013, were used as the primary source of turbine data points. The dataset was subsequently revised and reposted as described in the revision histories for the report. Verification of the turbine positions was done by visual interpretation using high-resolution aerial imagery in Environmental Systems Research Institute (Esri) ArcGIS Desktop. Turbines without Federal Aviation Administration Obstacles Repository System numbers were visually identified and point locations were added to the collection. We estimated a locational error of plus or minus 10 meters for turbine locations. Wind farm facility names were identified from publicly available facility datasets. Facility names were then used in a Web search of additional industry publications and press releases to attribute additional turbine information (such as manufacturer, model, and technical specifications of wind turbines). Wind farm facility location data from various wind and energy industry sources were used to search for and digitize turbines not in existing databases. Technical specifications for turbines were assigned based on the wind turbine make and model as described in literature, specifications listed in the Federal Aviation Administration Digital Obstacles File, and information on the turbine manufacturer’s Web site. Some facility and turbine information on make and model did not exist or was difficult to obtain. Thus, uncertainty may exist for certain turbine specifications. That uncertainty was rated and a confidence was recorded for both location and attribution data quality.

Data Series↗

ʻŌhiʻa Lehua rainforest: born among Hawaiian volcanoes, evolved in isolation: the story of a dynamic ecosystem with relevance to forests worldwide

In the early 1970s, a multidisciplinary team of forest biologists began a study of Hawaiian ecosystems under the International Biological Program (IBP). Research focus was on the intact native ecosystems in and around Hawai'i Volcanoes National Park, in particular the ʻŌhiʻa Lehua rainforest. Patches of dead ʻŌhiʻa stands had been reported from the windward slopes of Mauna Loa and Mauna Kea. Subsequent air photo analyses by a team of US and Hawai'i State foresters discovered rapidly spreading ʻŌhiʻa dieback, also called ʻŌhiʻa forest decline. A killer disease was suspected to destroy the Hawaiian rain forest in the next 15-25 years. Ecological research continued with a focus on the dynamics of the Hawaiian rainforest. This book explains what really happened and why the ʻŌhiʻa rainforest survived in tact as everyone can witness today.

Hawai'i↗

Hydrologic modeling and river corridor applications of HY_Features concepts

The WaterML2: Part 3 - Surface Hydrology Features (HY_Features) Conceptual Model was published by OGC in 2018. This report documents the use of HY_Features concepts in support of two key tasks: (1) local to continental hydrologic modeling; and (2) referencing river corridor data to hydrographic networks. The presented use cases are applicable in hydroscience research and assessments, water resources engineering practices, and drought and flood responses. Before the HY_Features conceptual model there was no internationally recognized standard for the design of software and data for the hydroscience and engineering community. This report presents progress towards a logical data model that interprets the abstract HY_Features concepts for use in geospatial workflows, modeling applications, and web data systems that integrate hydrologic data. The use cases addressed include: (1) hydrologic model control volume definition; (2) hydrologic network connectivity; (3) characterization of catchments with landscape and atmospheric data; (4) river corridor characterization; (5) hydrologic location; and (6) flow network location. Each use case is described briefly along with an analysis of the information requirements. This report presents a summary of the logical model designed to satisfy the needs of these use cases and a summary of updates and changes proposed for HY_Features. Changes for consideration by the HY_Features Standards Working Group include the following. Provide more clarity on the inherited properties and associations of features that "realize" the catchment and nexus concepts from HY_Features. Add nexus realization feature types to represent the outlet of catchments that are "frontal" (terminate to the ocean or a large waterbody) or "inland sinks." Add a "HY_Flowline" feature as a superclass of HY_Flowpath providing linear referencing on waterbodies that are not catchment realizations. Add an association or interface to support connection between surface catchments and hydrogeologic units.

OGC Public Engineering Report↗

Vascular Plant and Vertebrate Inventory of Saguaro National Park, Rincon Mountain District

Executive Summary This report summarizes the results of the first comprehensive inventory of plants and vertebrates at the Rincon Mountain District (RMD) of Saguaro National Park, Arizona. From 2001 to 2003 we surveyed for vascular plants and vertebrates (amphibians, reptiles, birds, and mammals) at the district to document the presence of species within its boundaries. Park staff also surveyed for medium and large mammals using infrared-triggered cameras from 1999 to 2005. This report summarizes the methods and results of these two efforts. Our spatial sampling design was ambitious and was one of the first of its kind in the region to colocate study sites for vegetation and vertebrates using a stratified random design. We also chose the location of some study sites non-randomly in areas that we thought would have the highest species richness. Because we used repeatable study designs and standardized field methods, these inventories can serve as the first step in a biological monitoring program for the district. We also provide an important overview of most previous survey efforts in the district. We use data from our inventory and other surveys to compile species lists and to assess inventory completeness. With the exception of plants, our survey effort was the most comprehensive ever undertaken in the district. We recorded a total of 801 plant and vertebrate species, including 50 species not previously found in the district (Table 1) of which five (all plants) are non-native species. Based on a review of our inventory and past research at the district, there have been a total of 1,479 species of plants and vertebrates found there. We believe inventories for all taxonomic groups are nearly complete. In particular, the plant, amphibian and reptile, and mammal species lists are the most complete of any comparably large natural area of the 'sky island' region of southern Arizona and adjacent Mexico. For each taxon-specific chapter we discuss patterns of species richness and environmental determinants of these patterns. For all groups except medium and large mammals, the low elevation stratum (<4,000 feet) contained the highest species richness, after accounting for differences in survey effort among strata. This is consistent with known patterns of species richness in the sky island mountain ranges. Using data on relative abundance for plants and birds, we were able to identify a number of distinct ecological communities, which were consistent with known patterns in the sky islands. Our review of species lists and park records reveals that the district has lost species, particularly plants and mammals, in the past few decades. Because of the district's close proximity to the rapidly growing city of Tucson, there are a number of development-related threats that could cause additional species loss or decline in abundance of some species. In particular, the increasing groundwater pumping near Rincon Creek, the most species-rich area in the park, is likely to impact the unique riparian vegetation and animals of that area. We discuss this and other demands on the ecological integrity of the district. We also recommend additional inventory, monitoring, and research studies.

Open-File Report↗

Metallogenic belt and mineral deposit maps of northeast Asia

This report contains explanatory material and summary tables for lode mineral deposits and placer districts (Map A, sheet 1) and metallogenic belts of Northeast Asia (Maps B, C, and D on sheets 2, 3, and 4, respectively). The map region includes eastern Siberia, southeastern Russia, Mongolia, northeast China, and Japan. A large group of geologists—members of the joint international project, Major Mineral Deposits, Metallogenesis, and Tectonics of Northeast Asia—prepared the maps, tables, and introductory text. This is a cooperative project with the Russian Academy of Sciences, Mongolian Academy of Sciences, Mongolian National University, Ulaanbaatar, Mongolian Technical University, Mineral Resources Authority of Mongolia, Geological Research Institute, Jilin University, China Geological Survey, Korea Institute of Geoscience and Mineral Resources, Geological Survey of Japan, and U.S. Geological Survey. This report is one of a series of reports on the mineral resources, geodynamics, and metallogenesis of Northeast Asia. Companion studies include (1) a detailed geodynamics map of Northeast Asia (Parfenov and others, 2003); (2) a compilation of major mineral deposit models (Rodionov and Nokleberg, 2000; Rodionov and others, 2000); (3) a series of metallogenic belt maps (Obolenskiy and others, 2004); (4) location map of lode mineral deposits and placer districts of Northeast Asia (Ariunbileg and others, 2003b); (5) descriptions of metallogenic belts (Rodionov and others, 2004); (6) a database on significant metalliferous and selected nonmetalliferous lode deposits and selected placer districts (Ariunbileg and others, 2003a); and (7) a series of summary project publications (Ariunbileg and 74 others, 2003b).

Asia↗

Man against volcano: The eruption on Heimaey, Vestmann Islands, Iceland

The U.S. Geological Survey carries out scientific studies in the geological, hydrological, and cartographic sciences generally within the 50 states, but also in cooperation with scientific organizations in many foreign countries for the investigation of unusual earth science phenomena throughout the world. The following material discusses the impact of the 1973 volcanic eruption of Eldfell on the fishing port of Vestmannaeyjar on the island of Heimaey, Iceland. Before the eruption was over, approximately one-third of the town of Vestmannaeyjar had been obliterated but, more importantly, the potential damage had been reduced markedly by the spraying of seawater onto the advancing lava flows, causing them to be slowed, stopped, or diverted from the undamaged portion of the town. The Survey's interest and involvement in the Heimaey eruption in Iceland was occasioned by the possibility that the procedures used to control the course of the flowing lava and to reduce the damage in a modern town may some day be needed in Hawaii and possibly even in the continental United States. This publication is based on the observations of two USGS geologists, Richard S. Williams, Jr. and James G. Moore, as well as on information from the Icelandic Ministry for Foreign Affairs, Icelandic scientists' reports through the Center for Short-Lived Phenomena, and other published scientific reports. A number of Icelandic scientists studied the scientific aspects of the eruption and the engineering aspects of the control of lava flows, in particular, Professors Thorbjb'rn Sigurgeirsson and Sigurdur Thorarinsson of the University of Iceland Science Institute. Also, Icelandic governmental officials provided logistical and other support, in particular, Mr. Steingnmur Hermannsson, Director, Icelandic National Research Council and Professor Magnus Magnusson, Director, University of Iceland Science Institute.

Vestmannaeyjar↗

Water resources activities of the USGS, 1987

Effective management of water resources requires an understanding of hydrologic systems and the factors that determine the distribution, availability, and quality of water. Within the Federal Government, the U.S. Geological Survey has the principal responsibility for providing hydrologic information and for appraising the Nation's water resources. The water resources activities of the U.S. Geological Survey are diverse, ranging from research investigations of specific aspects of the hydrologic cycle to large programs of regional water-resources investigations, such as the Regional Aquifer System Analyses. This report describes the U.S. Geological Survey's water resources activities. Some activities, such as the acid rain program, are mandated by line items in the Survey's fiscal year 1987 budget. Others, such as floods, sediment, and snow and ice, are topics of general interest to the water resources community. Still others are related to current water issues, such as nonpoint sources of pollution, the irrigation drainage problem of the western San Joaquin Valley, and national ground-water protection. In many cases, there is considerable overlap in the topical descrip-tions. The Survey's water resources research program, for example, conducts investigations that are applicable to virtually all of the activities listed in this book. Similarly, projects in the Federal-State Cooperative Program cover multiple aspects of water resources. For these reasons, the sums associated with funding for each of the activities listed exceeds by a considerable amount the Survey's budget for water resources activities. The report first describes the water-resources mission of the U.S. Geological Survey and discusses the principal sources of funds that support the activities. The remainder of the report consists of descriptions of 39 of the most significant water resources activities. An index appears at the end of the report. Each description of a significant water activity has the following parts: Introduction--the problem or issue addressed by the activity and a statement of purpose. Activities--examples of investigations underway. Recent accomplishments--examples of findings or achievements. Funding--an indication of the size of the program in terms of funding. Where possible, the funding of activities is given by source for fiscal years 1983 to 1987.

Open-File Report↗

Caribou use of habitat near energy development in Arctic Alaska

Increasing demands for energy have generated interest in expanding oil and gas production on the North Slope of Alaska, raising questions about the resilience of barren-ground caribou populations to new development. Although the amount of habitat lost directly to energy development in the Arctic will likely be relatively small, there are significant concerns about habitat that may be indirectly impacted due to caribou avoidance behaviors. Behavioral responses to energy development for wildlife have been well-documented, but such responses are often assumed to dissipate over time, despite scant information on the ability of animals to habituate. To understand the long-term effects of energy development on barren-ground caribou we investigated the behavior of the Central Arctic Herd in northern Alaska, which has been exposed to oil development on its summer range for approximately 40 years. Using recent (2015-2017) location data from GPS collared females, we conducted a zone of influence analysis to assess whether caribou reduced their use of habitat near energy development, and if so, the distance the effects attenuated. We conducted this analysis for the calving, post-calving and mosquito harassment periods when caribou exhibit distinct resource selection patterns, and contrasted our results to past research that investigated the responses of the Central Arctic Caribou Herd immediately following the construction of the oil fields. Despite the long-term presence of energy development within the Central Arctic Herd summer range, we found that female caribou exhibited avoidance responses to infrastructure during all time periods, although the effects waned across the summer. Caribou reduced their use of habitat within 5 km of development during the calving period, within 2 km during the post-calving period, and within 1 km during the mosquito harassment period, areas which were predicted to overlap 12%, 15% and 17% of important calving, post-calving, and mosquito habitat areas, respectively. During the calving period, the indirect effects we observed were similar to those observed in past research, whereas during the post-calving and mosquito periods, we detected avoidance responses which had not been previously reported. These findings corroborate a growing body of evidence suggesting that habituation to industrial development in Arctic caribou is likely to be weak or absent, and emphasizes the value of minimizing the footprint of infrastructure within important seasonal habitat areas to reduce behavioral impacts to barren-ground caribou.

Alaska↗

Sediment movement along the U.S. east coast continental shelf-II. Modelling suspended sediment concentration and transport rate during storms

Long-term near-bottom wave and current observations and a one-dimensional sediment transport model are used to calculate the concentration and transport of sediment during winter storms at 60-80 m water depth along the southern flank of Georges Bank and in the Mid-Atlantic Bight. Calculations are presented for five stations, separated by more than 600 km alongshelf, that have different bottom sediment texture, bedforms and current conditions. A modified version of the sediment transport model presented by Grant and Glenn (1983, Technical Report to the American Gas Association), Glenn (1983, D.Sc. Thesis, M.I.T.), and Glenn and Grant (1987, Journal of Geophysical Research, 92, 8244-8264) is used to examine the influence of wave-current interaction, sediment stratification, and limitations on the erodibility of the bottom sediments on the concentration of sediment in the water column and on transport. Predicted suspended sediment concentrations are higher than observed, based on beam transmissometer measurements, unless an erosion limit of order a few millimeters for sediments finer than 94 ??m is imposed. The agreement between predicted and measured beam attenuation is better at stations that have significant amounts of silt plus clay in the surficial sediments than for stations with sandy sediments. Sediment concentrations during storms estimated by Moody et al. (1987, Continental Shelf Research, 7, 609-628) are within 50% of the model predictions. Sediment transport rates for sediments 94 ??m and finer are determined largely by the concentrations in the surficial sediment and the erosion depth limit. Large alongshelf transports in the direction of storm-driven currents are inferred for stations in the Mid-Atlantic Bight. During a 115-day period in winter 1979-1980, the net transport of sediment along the shelf was westward; benthic storms (defined as periods when the bottom wave stress exceeded the current stress by 2 dyn cm-2) occurred between 23 and 73% of the time, and greater than 91% of the net alongshelf transport was during storms. ?? 1990.

Georges Bank, Mid-Atlantic Bight↗

Female hatchling American kestrels have a larger hippocampus than males: A link with sexual size dimorphism?

The brain and underlying cognition may vary adaptively according to an organism’s ecology. As with all raptor species, adult American kestrels ( Falco sparverius ) are sexually dimorphic with females being larger than males. Related to this sexual dimorphism, kestrels display sex differences in hunting and migration, with females ranging more widely than males, suggesting possible sex differences in spatial cognition. However, hippocampus volume, the brain region responsible for spatial cognition, has not been investigated in raptors. Here, we measured hippocampus and telencephalon volumes in American kestrel hatchlings. Female hatchlings had a significantly larger hippocampus relative to the telencephalon and brain weight than males (∼12% larger), although telencephalon volume relative to brain weight and body size was similar between the sexes. The magnitude of this hippocampal sex difference is similar to that reported between male and female polygynous Microtus voles and migratory and non-migratory subspecies of Zonotrichia sparrows. Future research should determine if this sex difference in relative hippocampus volume of hatchling kestrels persists into adulthood and if similar patterns exist in other raptor species, thus potentially linking sex differences in the brain to sex differences of space use of adults in the wild.

Behavioural Brain Research↗

Ethoxyresorufin-O-deethylase (EROD) activity in fish as a biomarker of chemical exposure

This review compiles and evaluates existing scientific information on the use, limitations, and procedural considerations for EROD activity (a catalytic measurement of cytochrome P4501A induction) as a biomarker in fish. A multitude of chemicals induce EROD activity in a variety of fish species, the most potent inducers being structural analogs of 2,3,7,8-tetracholordibenzo- p -dioxin. Although certain chemicals may inhibit EROD induction/activity, this interference is generally not a drawback to the use of EROD induction as a biomarker. The various methods of EROD analysis currently in use yield comparable results, particularly when data are expressed as relative rates of EROD activity. EROD induction in fish is well characterized, the most important modifying factors being fish species, reproductive status and age, all of which can be controlled through proper study design. Good candidate species for biomonitoring should have a wide range between basal and induced EROD activity (e.g., common carp, channel catfish, and mummichog). EROD activity has proven value as a biomarker in a number of field investigations of bleached kraft mill and industrial effluents, contaminated sediments, and chemical spills. Research on mechanisms of CYP1A-induced toxicity suggests that EROD activity may not only indicate chemical exposure, but also may also precede effects at various levels of biological organization. A current research need is the development of chemical exposure-response relationships for EROD activity in fish. In addition, routine reporting in the literature of EROD activity in standard positive and negative control material will enhance confidence in comparing results from different studies using this biomarker.

Critical Reviews in Toxicology↗

Molecular testing of adult Pacific salmon and trout (Oncorhynchus spp.) for several RNA viruses demonstrates widespread distribution of piscine orthoreovirus in Alaska and Washington

This research was initiated in conjunction with a systematic, multiagency surveillance effort in the United States (U.S.) in response to reported findings of infectious salmon anaemia virus (ISAV) RNA in British Columbia, Canada. In the systematic surveillance study reported in a companion paper, tissues from various salmonids taken from Washington and Alaska were surveyed for ISAV RNA using the U.S.-approved diagnostic method, and samples were released for use in this present study only after testing negative. Here, we tested a subset of these samples for ISAV RNA with three additional published molecular assays, as well as for RNA from salmonid alphavirus (SAV), piscine myocarditis virus (PMCV) and piscine orthoreovirus (PRV). All samples ( n = 2,252; 121 stock cohorts) tested negative for RNA from ISAV, PMCV, and SAV. In contrast, there were 25 stock cohorts from Washington and Alaska that had one or more individuals test positive for PRV RNA; prevalence within stocks varied and ranged from 2% to 73%. The overall prevalence of PRV RNA-positive individuals across the study was 3.4% (77 of 2,252 fish tested). Findings of PRV RNA were most common in coho ( Oncorhynchus kisutch Walbaum) and Chinook ( O. tshawytscha Walbaum) salmon.

Alaska, Washington↗

Vitrinite reflectance data for the Greater Green River basin, southwestern Wyoming, northwestern Colorado, and northeastern Utah

The Greater Green River Basin is a large Laramide (Late Cretaceous through Eocene) structural and sedimentary basin that encompasses about 25,000 square miles in southwestern Wyoming, northwestern Colorado, and northeastern Utah (fig. 1). Important conventional oil and gas resources have been discovered and produced from reservoirs ranging in age from Cambrian through Tertiary (Law, 1996). In addition, an extensive overpressured basin - centered gas accumulation has also been identified in Cretaceous and Tertiary reservoirs by numerous researchers including Law (1984a, 1996), Law and others (1980, 1989), McPeek (1981), and Spencer (1987). The purpose of this report is to present new vitrinite reflectance data to be used in support of the U.S Geological Survey assessment of undiscovered oil and gas resources of the Greater Green River Basin. One hundred eighty-six samples were collected from Cretaceous and Tertiary coalbearing strata (figs. 1 and 2) in an effort to better understand and characterize the thermal maturation and burial history of potential source rocks. Two samples were from core, one from outcrop, and the remainder from well cuttings. These data were collected to supplement previously published data by Law (1984b), Pawlewicz and others (1986), Merewether and others (1987), and Garcia-Gonzalez and Surdam (1995) and are presented in table 1.

Colorado, Utah, Wyoming↗

Synthesis of downstream fish passage information at projects owned by the U.S. Army Corps of Engineers in the Willamette River Basin, Oregon

The U.S. Army Corps of Engineers (USACE) operates the Willamette Valley Project (Project) in northwestern Oregon, which includes a series of dams, reservoirs, revetments, and fish hatcheries. Project dams were constructed during the 1950s and 1960s on rivers that supported populations of spring Chinook salmon ( Oncorhynchus tshawytscha ), winter steelhead ( O. mykiss ), and other anadromous fish species in the Willamette River Basin. These dams, and the reservoirs they created, negatively affected anadromous fish populations. Efforts are currently underway to improve passage conditions within the Project and enhance populations of anadromous fish species. Research on downstream fish passage within the Project has occurred since 1960 and these efforts are documented in numerous reports and publications. These studies are important resources to managers in the Project, so the USACE requested a synthesis of existing literature that could serve as a resource for future decision-making processes. In 2016, the U.S. Geological Survey conducted an extensive literature review on downstream fish passage studies within the Project. We identified 116 documents that described studies conducted during 1960–2016. Each of these documents were obtained, reviewed, and organized by their content to describe the state-of-knowledge within four subbasins in the Project, which include the North Santiam, South Santiam, McKenzie, and Middle Fork Willamette Rivers. In this document, we summarize key findings from various studies on downstream fish passage in the Willamette Project. Readers are advised to review specific reports of interest to insure that study methods, results, and additional considerations are fully understood.

Oregon↗