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A guidebook to spatial datasets for conservation planning under climate change in the Pacific Northwest

This guidebook provides user-friendly overviews of a variety of spatial datasets relevant to conservation and management of natural resources in the face of climate change in the Pacific Northwest, United States. Each guidebook chapter was created using a standardized template to summarize a spatial dataset or a group of closely related datasets. Datasets were selected according to standardized criteria based on input through a collaborative process involving researchers and natural-resource managers throughout the Pacific Northwest region. In each chapter, basic spatial and temporal information is provided for the dataset, along with a conceptual overview, glossary of key terms, links to download data and supporting documentation, a brief methods summary describing how the dataset was created, guidelines for dataset interpretation, assessment of uncertainties along with evaluation of caveats and simplifying assumptions, and information about potential and actual conservation applications of the dataset. Collectively, this information provides natural-resource managers with “snapshots” of a variety of datasets representing diverse processes and conditions, including climate projections, changes in hydrologic conditions, vegetation and fire-regime shifts, animal habitat changes, species movements, and topographic and soil conditions relevant to climate change. Along with other types of data and site-specific information, the datasets described in this guidebook have the potential to inform management of valued natural resources throughout the Pacific Northwest region in the context of adaptation to changing climate conditions.

Idaho, Montana, Oregon, Washington

Nutrient scarcity as a selective pressure for mast seeding

Mast seeding is one of the most intriguing reproductive traits in nature. Despite its potential drawbacks in terms of fitness, the widespread existence of this phenomenon suggests that it should have evolutionary advantages under certain circumstances. Using a global dataset of seed production time series for 219 plant species from all of the continents, we tested whether masting behaviour appears predominantly in species with low foliar nitrogen and phosphorus concentrations when controlling for local climate and productivity. Here, we show that masting intensity is higher in species with low foliar N and P concentrations, and especially in those with imbalanced N/P ratios, and that the evolutionary history of masting behaviour has been linked to that of nutrient economy. Our results support the hypothesis that masting is stronger in species growing under limiting conditions and suggest that this reproductive behaviour might have evolved as an adaptation to nutrient limitations and imbalances.

Nature Plants

Continuous Temperature and Water-Level Data Collected for a Heat Tracer Study on a Selected Reach of Tri-State Canal, Western Nebraska, 2007

The water supply in parts of the North Platte River Basin in the Nebraska Panhandle has been designated as fully appropriated or over appropriated by the Nebraska Department of Natural Resources. Recent legislation (LB 962) requires the North Platte Natural Resources District and the Nebraska Department of Natural Resources to develop an Integrated Management Plan to balance ground- and surface-water supply and demand within the North Platte Natural Resources District. For a ground-water-flow model to accurately simulate existing or future ground-water and surface-water conditions, accurate estimates of specific input variables such as streambed conductance or canal-seepage rates are required. As of 2008, the values input into ground-water models were estimated on the basis of interpreted lithology from test holes and geophysical surveys. Often, contrasts of several orders of magnitude exist for streambed conductance among the various sediment textures present locally, and thin, near-surface layers of fine sediment can clog the streambed, substantially reducing conductance. To accurately quantify the rates of leakage from irrigation canals and estimate ground-water recharge, the U.S. Geological Survey, in cooperation with the North Platte Natural Resources District, collected continuous temperature and water-level data to use heat as a tracer for a selected reach of Tri-State Canal west of Scottsbluff, Nebraska. Continuous records of subsurface temperature, ground-water level, canal stage, and water temperature, and sediment core data are presented in this report. Subsurface temperature was monitored at four vertical sensor arrays of thermocouples installed at various depths beneath the canal bed from March through September 2007. Canal stage and water temperature were measured from June to September 2007. Ground-water level was recorded continuously in an observation well drilled near the subsurface temperature monitoring site. These data sets were collected for use as inputs for a computer model to estimate the vertical hydraulic conductivity. Before the initiation of flow, diurnal variations in subsurface temperature occurred because of daytime heating and nighttime cooling of bed sediment. Flow in Tri-State Canal was first detected on June 16 at the monitoring site as a disruption in the temperature signal in the shallowest thermocouple in all four vertical sensor arrays. This disruption in the temperature pattern occurred in deeper thermocouples at slightly later times during the rapid infiltration of canal water. The ground-water level began to rise approximately 23 hours after flow was first detected at the monitoring site. Canal stage rose for 7 days until the maximum flow capacity of the canal was approached on June 23, 2007. Measured water temperatures ranged from 18 to 25 degrees Celsius (C) while the canal was flowing near maximum capacity. Small diurnal variations of 1.0 to 1.5 degrees C in water temperature were recorded during this time. Measured ground-water levels rose constantly during the entire irrigation season until levels peaked on September 3, 2007, 3 days after diversions to Tri-State Canal ceased.

Data Series

Improved enrichment factor calculations through principal component analysis: Examples from soils near breccia pipe uranium mines, Arizona, USA

The enrichment factor (EF) is a widely used metric for determining how much the presence of an element in a sampling media has increased relative to average natural abundance because of human activity. Calculation of an EF requires the selection of both a background composition and a reference element, choices that can strongly influence the result of the calculation. Here, it is shown how carefully applied, classical principal component analysis (PCA) examined via biplots can guide the selections of background compositions and reference elements. Elemental data were treated using the centered log ratio (CLR) transformation, and multiple subsets of major and trace elements were examined to gain different perspectives. The methodology was applied to a dataset of elemental soil concentrations from around breccia pipe uranium mines in Arizona, U.S.A., with most samples collected via incremental sampling methodology. Storage of ore at the surface creates the potential for wind dispersal of ore-derived material. Uranium was found to be the best individual tracer of dispersal of ore-derived material to nearby soils, with EF values up to 75. Sulfur, As, Mo, and Cu were also enriched but to lesser degrees. The results demonstrate several practical benefits of a PCA in these situations: (1) the ability to identify one or more elements best suited to distinguish a specific source of enrichment from background composition; (2) understanding how background compositions vary within and between sites; (3) identification of samples containing enriched or anthropogenic materials based upon their integrated, multi-element composition. Calculating the most representative EF values is useful for numerical assessment of enrichment, whether anthropogenic or natural. As shown here, however, the PCA and biplot method provide a visual approach that integrates information from all elements for a given subset of data in a manner that yields geochemical insights beyond the power of the EF.

Arizona

Detection of conduit-controlled ground-water flow in northwestern Puerto Rico using aerial photograph interpretation and geophysical methods

The development potential of ground-water resources in the karst limestone of northwestern Puerto Rico, in an area extending from the Río Camuy to Aguadilla, is uncertain as a result of limited knowledge of the location of areas where a high density of cavities (interconnected fractures, conduits, and other dissolution features) might suggest the occurrence of high water yields. The presence in northwestern Puerto Rico of numerous coastal submarine springs, cavernous porosity in some of the wells, and rivers with entrenched and underground paths, indicate that it is probable that water-bearing, subterranean interconnected cavities occur in the area between the Río Camuy and Aguadilla. The number of exploratory wells needed to determine the location of these conduits or zones of enhanced secondary porosity could be substantially reduced if more information were available about the location of these subterranean features, greatly reducing the drilling costs associated with a trial-and-error exploratory process. A 3-year study was conducted by the U.S. Geological Survey, in cooperation with the Puerto Rico Aqueduct and Sewer Authority, to detect the presence of cavities that might suggest the occurrence of conduit-controlled groundwater flow. Aerial photographs, geologic and topographic maps, and field reconnaissance were used to identify such linear terrain features as ridges, entrenched canyons, and fracture traces. Natural potential and gravity geophysical methods were also used. The following sites were selected for the aerial photograph interpretation and geophysical testing: Caimital Bajo uplands and former Ramey Air Force Base in Aguadilla; Quebrada de los Cedros between Aguadilla and Isabela; the University of Puerto Rico Agricultural Experiment Station, Otilio dairy farm, and Pozo Brujo in Isabela; the Monte Encantado area in Moca and Isabela; and the Rio Camuy cave system in Hatillo and Camuy. In general, the degree of success varied with site and the geophysical method used. At some sites such as Pozo Brujo, the University of Puerto Rico Agricultural Experiment Station, and Monte Encantado area, natural potential anomalies strongly suggest the existence of conduits with flowing water. At most sites, however, the results obtained did not clearly reveal the presence of subsurface cavities that might be associated with the occurrence of conduit-controlled ground-water flow. Sites such as the University of Puerto Rico Agricultural Experiment Station, Pozo Brujo, and Quebrada de los Cedros warrant a more detailed analysis, including a test well drilling phase to confirm the presence of suspected high-yield water-bearing zones.

Water-Resources Investigations Report

Design approaches in quarrying and pit-mining reclamation

Reclaimed mine sites have been evaluated so that the public, industry, and land planners may recognize there are innovative designs available for consideration and use. People tend to see cropland, range, and road cuts as a necessary part of their everyday life, not as disturbed areas despite their high visibility. Mining also generates a disturbed landscape, unfortunately one that many consider waste until reclaimed by human beings. The development of mining provides an economic base and use of a natural resource to improve the quality of human life. Equally important is a sensitivity to the geologic origin and natural pattern of the land. Wisely shaping out environment requires a design plan and product that responds to a site's physiography, ecology, function, artistic form, and publication perception. An examination of selected sites for their landscape design suggested nine approaches for mining reclamation. The oldest design approach around is nature itself. Humans may sometimes do more damage going to an area in the attempt to repair it. Given enough geologic time, a small-site area, and stable adjacent ecosystems, disturbed areas recover without mankind's input. Visual screens and buffer zones conceal the facility in a camouflage approach. Typically, earth berms, fences, and plantings are used to disguise the mining facility. Restoration targets social or economic benefits by reusing the site for public amenities, most often in urban centers with large populations. A mitigation approach attempts to protect the environment and return mined areas to use with scientific input. The reuse of cement, building rubble, macadam meets only about 10% of the demand from aggregate. Recognizing the limited supply of mineral resources and encouraging recycling efforts are steps are steps in a renewable resource approach. An educative design approach effectively communicates mining information through outreach, land stewardship, and community service. Mine sites used for art show a celebration of beauty and experience -- abstract geology. The last design approach combines art and science in a human-nature ecosystem termed integration. With environmental concerns, an operating or reclaimed mine site can no longer be considered isolated from its surroundings. Site analysis of mine works needs to go beyond site-specific information and relate to the regional context of the greater landscape. Understanding design approach can turn undesirable features (mines and pits) into something perceived as desirable by the public.

Book

Regional regression equations for estimation of natural streamflow statistics in Colorado

The U.S. Geological Survey (USGS), in cooperation with the Colorado Water Conservation Board and the Colorado Department of Transportation, developed regional regression equations for estimation of various streamflow statistics that are representative of natural streamflow conditions at ungaged sites in Colorado. The equations define the statistical relations between streamflow statistics (response variables) and basin and climatic characteristics (predictor variables). The equations were developed using generalized least-squares and weighted least-squares multilinear regression reliant on logarithmic variable transformation. Streamflow statistics were derived from at least 10 years of streamflow data through about 2007 from selected USGS streamflow-gaging stations in the study area that are representative of natural-flow conditions. Basin and climatic characteristics used for equation development are drainage area, mean watershed elevation, mean watershed slope, percentage of drainage area above 7,500 feet of elevation, mean annual precipitation, and 6-hour, 100-year precipitation. For each of five hydrologic regions in Colorado, peak-streamflow equations that are based on peak-streamflow data from selected stations are presented for the 2-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-year instantaneous-peak streamflows. For four of the five hydrologic regions, equations based on daily-mean streamflow data from selected stations are presented for 7-day minimum 2-, 10-, and 50-year streamflows and for 7-day maximum 2-, 10-, and 50-year streamflows. Other equations presented for the same four hydrologic regions include those for estimation of annual- and monthly-mean streamflow and streamflow-duration statistics for exceedances of 10, 25, 50, 75, and 90 percent. All equations are reported along with salient diagnostic statistics, ranges of basin and climatic characteristics on which each equation is based, and commentary of potential bias, which is not otherwise removed by log-transformation of the variables of the equations from interpretation of residual plots. The predictor-variable ranges can be used to assess equation applicability for ungaged sites in Colorado.

Colorado

Selected field and analytical methods and analytical results in the Dutch Flats area, western Nebraska, 1995-99

A study of the water resources of the Dutch Flats area in the western part of the North Platte Natural Resources District, western Nebraska, was conducted from 1995 through 1999 to describe the surface water and hydrogeology, the spatial distribution of selected water-quality constituents in surface and ground water, and the surface-water/ground-water interaction in selected areas. This report describes the selected field and analytical methods used in the study and selected analytical results from the study not previously published. Specifically, dissolved gases, age-dating data, and other isotopes collected as part of an intensive sampling effort in August and November 1998 and all uranium and uranium isotope data collected through the course of this study are included in the report.

Nebraska

Stream-temperature characteristics in Georgia

Stream-temperature measurements for 198 periodic and 22 daily record stations were analyzed using a harmonic curve-fitting procedure. Statistics of data from 78 selected stations were used to compute a statewide stream-temperature harmonic equation, derived using latitude, drainage area, and altitude for natural streams having drainage areas greater than about 40 square miles. Based on the 1955-84 reference period, the equation may be used to compute long-term natural harmonic stream-temperature coefficients to within an on average of about 0.4? C. Basin-by-basin summaries of observed long-term stream-temperature characteristics are included for selected stations and river reaches, particularly along Georgia's mainstem streams. Changes in the stream- temperature regimen caused by the effects of development, principally impoundments and thermal power plants, are shown by comparing harmonic curves and coefficients from the estimated natural values to the observed modified-condition values.

Georgia

Survey of aquatic macroinvertebrates and amphibians at Wupatki National Monument, Arizona, USA: An evaluation of selected factors affecting species richness in ephemeral pools

Ephemeral aquatic habitats in Wupatki National Monument vary from naturally formed pools in arroyos over 5000 years old, to constructed catchment basins with ages estimated at 60-1000+ years old, and borrow pits and stock ponds 30-60 years old. The different ages of these pools provide different histories of colonization by amphibians and aquatic invertebrates, especially temporary pool specialists such as spadefoot toads and branchiopod crustaceans. Ten pools of five different origins and ages were surveyed in August and/or September 1997 for aquatic organisms; a total of 13 surveys were conducted. Twenty-two taxa were found, with the number of species in a pool during any survey ranging from one to 10. Species composition of the communities changed from one sampling date to the next within individual pools. Community structure is an amalgam of species with different dispersal mechanisms that are influenced by different pool characteristics. Age appears to have little effect overall, but may have influenced branchiopod presence/absence. Distance to permanent water, frequency of disturbance, and current pool size were correlated with presence/absence of some species.

Conference Paper

Adjusted peak-flow frequency estimates for selected streamflow-gaging stations in or near Montana based on data through water year 2011: Chapter D in Montana StreamStats

The climatic conditions of the specific time period during which peak-flow data were collected at a given streamflow-gaging station (hereinafter referred to as gaging station) can substantially affect how well the peak-flow frequency (hereinafter referred to as frequency) results represent long-term hydrologic conditions. Differences in the timing of the periods of record can result in substantial inconsistencies in frequency estimates for hydrologically similar gaging stations. Potential for inconsistency increases with decreasing peak-flow record length. The representativeness of the frequency estimates for a short-term gaging station can be adjusted by various methods including weighting the at-site results in association with frequency estimates from regional regression equations (RREs) by using the Weighted Independent Estimates (WIE) program. Also, for gaging stations that cannot be adjusted by using the WIE program because of regulation or drainage areas too large for application of RREs, frequency estimates might be improved by using record extension procedures, including a mixed-station analysis using the maintenance of variance type I (MOVE.1) procedure. The U.S. Geological Survey, in cooperation with the Montana Department of Transportation and the Montana Department of Natural Resources and Conservation, completed a study to provide adjusted frequency estimates for selected gaging stations through water year 2011. The purpose of Chapter D of this Scientific Investigations Report is to present adjusted frequency estimates for 504 selected streamflow-gaging stations in or near Montana based on data through water year 2011. Estimates of peak-flow magnitudes for the 66.7-, 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities are reported. These annual exceedance probabilities correspond to the 1.5-, 2-, 2.33-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-year recurrence intervals, respectively. The at-site frequency estimates were adjusted by weighting with frequency estimates from RREs using the WIE program for 438 selected gaging stations in Montana. These 438 selected gaging stations (1) had periods of record less than or equal to 40 years, (2) represented unregulated or minor regulation conditions, and (3) had drainage areas less than about 2,750 square miles. The weighted-average frequency estimates obtained by weighting with RREs generally are considered to provide improved frequency estimates. In some cases, there are substantial differences among the at-site frequency estimates, the regression-equation frequency estimates, and the weighted-average frequency estimates. In these cases, thoughtful consideration should be applied when selecting the appropriate frequency estimate. Some factors that might be considered when selecting the appropriate frequency estimate include (1) whether the specific gaging station has peak-flow characteristics that distinguish it from most other gaging stations used in developing the RREs for the hydrologic region; and (2) the length of the peak-flow record and the general climatic characteristics during the period when the peak-flow data were collected. For critical structure-design applications, a conservative approach would be to select the higher of the at-site frequency estimate and the weighted-average frequency estimate. The mixed-station MOVE.1 procedure generally was applied in cases where three or more gaging stations were located on the same large river and some of the gaging stations could not be adjusted using the weighted-average method because of regulation or drainage areas too large for application of RREs. The mixed-station MOVE.1 procedure was applied to 66 selected gaging stations on 19 large rivers. The general approach for using mixed-station record extension procedures to adjust at-site frequencies involved (1) determining appropriate base periods for the gaging stations on the large rivers, (2) synthesizing peak-flow data for the gaging stations with incomplete peak-flow records during the base periods by using the mixed-station MOVE.1 procedure, and (3) conducting frequency analysis on the combined recorded and synthesized peak-flow data for each gaging station. Frequency estimates for the combined recorded and synthesized datasets for 66 gaging stations with incomplete peak-flow records during the base periods are presented. The uncertainties in the mixed-station record extension results are difficult to directly quantify; thus, it is important to understand the intended use of the estimated frequencies based on analysis of the combined recorded and synthesized datasets. The estimated frequencies are considered general estimates of frequency relations among gaging stations on the same stream channel that might be expected if the gaging stations had been gaged during the same long-term base period. However, because the mixed-station record extension procedures involve secondary statistical analysis with accompanying errors, the uncertainty of the frequency estimates is larger than would be obtained by collecting systematic records for the same number of years in the base period.

Montana

Pesticides in U.S. streams and groundwater

A 10­-year study by the U.S. Geological Survey’s (USGS’s) National Water-­Quality Assessment (NAWQA) Program provides a national-­scale view of pesticide occurrence in streams and groundwater. The 1992-2001 study builds upon a preliminary analysis from NAWQA’s first phase of studies during 1992-1996 (1, 2). Pesticide data available from various studies prior to 1992 did not allow national assessment because of limited and variable geographic coverage (usually focusing on individual states or regions), sparse and inconsistent inclusion of pesticides in use, and variable sampling designs (3-5). The expanded geographic coverage and improved data following 10 years of study (Figure 1) confirm and reinforce previously reported findings and enable more detailed analyses of each topic. This article summarizes selected findings from a comprehensive report (6), with a focus on the nature of pesticide occurrence and potential significance to human health and stream ecosystems. Information on study design and methods as well as additional analysis of geographic patterns and trends in relation to use and management practices are available in the full report (6).

Environmental Science & Technology

Techniques for estimating peak-streamflow frequency for unregulated streams and streams regulated by small floodwater retarding structures in Oklahoma

Statewide regression equations for Oklahoma were determined for estimating peak discharge and flood frequency for selected recurrence intervals from 2 to 500 years for ungaged sites on natural unregulated streams. The most significant independent variables required to estimate peak-streamflow frequency for natural unregulated streams in Oklahoma are contributing drainage area, main-channel slope, and mean-annual precipitation. The regression equations are applicable for watersheds with drainage areas less than 2,510 square miles that are not affected by regulation from manmade works. Limitations on the use of the regression relations and the reliability of regression estimates for natural unregulated streams are discussed. Log-Pearson Type III analysis information, basin and climatic characteristics, and the peak-stream-flow frequency estimates for 251 gaging stations in Oklahoma and adjacent states are listed. Techniques are presented to make a peak-streamflow frequency estimate for gaged sites on natural unregulated streams and to use this result to estimate a nearby ungaged site on the same stream. For ungaged sites on urban streams, an adjustment of the statewide regression equations for natural unregulated streams can be used to estimate peak-streamflow frequency. For ungaged sites on streams regulated by small floodwater retarding structures, an adjustment of the statewide regression equations for natural unregulated streams can be used to estimate peak-streamflow frequency. The statewide regression equations are adjusted by substituting the drainage area below the floodwater retarding structures, or drainage area that represents the percentage of the unregulated basin, in the contributing drainage area parameter to obtain peak-streamflow frequency estimates.

Oklahoma

Evaluation of Landsat-7 SLC-off image products for forest change detection

Since July 2003, Landsat-7 ETM+ has been operating without the scan line corrector (SLC), which compensates for the forward motion of the satellite in the imagery acquired. Data collected in SLC-off mode have gaps in a systematic wedge-shaped pattern outside of the central 22 km swath of the imagery; however, the spatial and spectral quality of the remaining portions of the imagery are not diminished. To explore the continued use of Landsat-7 ETM+ SLC-off imagery to characterize change in forested environments, we compare the change detection results generated from a reference image pair (a 1999 Landsat-7 ETM+ image and a 2003 Landsat-5 TM image) with change detection results generated from the same 1999 Landsat-7 ETM+ image coupled with three different 2003 Landsat-7 SLC-off products: unremediated SLC-off (i.e., with gaps); histogram-based gap-filled; and segment-based gap-filled. The results are compared on both a pixel and polygon basis; on a pixel basis, the unremediated SLC-off product missed 35% of the change identified by the reference data, and the histogram- and segment-based gap-filled products missed 23% and 21% of the change, respectively. When using forest inventory polygons as a context for change (to reduce commission error), the amount of change missed was 31%, 14%, and 12% for the each of the unremediated, histogram-based gap-filled, and segment-based gap-filled products, respectively. Our results indicate that over the time period considered, and given the types and spatial distribution of change events within our study area, the gap-filled products can provide a useful data source for change detection in forested environments. The selection of which product to use is, however, very dependent on the nature of the application and the spatial configuration of change events. ?? 2008 Government of Canada.

Canadian Journal of Remote Sensing

Immunogenetics and resistance to avian malaria in Hawaiian honeycreepers (Drepanidinae)

Although a number of factors have contributed to the decline and extinction of Hawai‘i’s endemic terrestrial avifauna, introduced avian malaria ( Plasmodium relicturn ) is probably the single most important factor preventing recovery of these birds in low-elevation habitats. Continued decline in numbers, fragmentation of populations, and extinction of species that are still relatively common will likely continue without new, aggressive approaches to managing avian disease. Methods of intervention in the disease cycle such as chemotherapy and vaccine development are not feasible because of efficient immune-evasion strategies evolved by the parasite, technical difficulties associated with treating wild avian populations, and increased risk of selection for more virulent strains of the parasite. We are investigating the natural evolution of disease resistance in some low-elevation native bird populations, particularly Hawai‘i ‘Amakihi ( Hemignathus virens ), to perfect genetic methods for identifying individuals with a greater immunological capacity to survive malarial infection. We are focusing on genetic analyses of the major histocompatibility complex, due to its critical role in both humoral and cell-mediated immune responses. In the parasite, we are evaluating conserved ribosomal genes as well as variable genes encoding cell-surface molecules as a first step in developing a better understanding of the complex interactions between malarial parasites and the avian immune system. A goal is to provide population managers with new criteria for maintaining long-term population stability for threatened species through the development of methods for evaluating and maintaining genetic diversity in small populations at loci important in immunological responsiveness to pathogens.

Hawai'i

Hydrologic reconnaissance of Curlew Valley, Utah and Idaho

This report is the fifth in a series of reports prepared by the U. S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, that describe the water resources of selected basins in western Utah. Previously published reports in this series are listed on page 35 and the areas covered by them are shown in figure 1. The purpose of this report is to present available hydrologic data on the Utah part of Curlew Valley, to provide an evaluation of the potential water-resource development of the valley, and to identify needed studies that would help provide an understanding of the valley's water supply.

Idaho, Utah

Hydrology reconnaissance of the Sink Valley area, Tooele and Box Elder Counties, Utah

This is the sixth in a series of reports by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, which describe the water resources of selected basins in western Utah. Areas covered by previously published reports in this series are shown in figure 1 and are listed on page 29. The purpose of this report is to present available hydrologic data on the Sink Valley (Puddle Valley) area, to provide an evaluation of the potential for water-resource development in the area, and to serve as a basis for planning possible later detailed investigations.

Utah

Hydrologic reconnaissance of the Blue Creek Valley area, Box Elder County, Utah

This report is the tenth in a series of reports prepared by the U. S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, that describe the water resources of selected areas in northwestern Utah. The purpose of this report is to present available hydrologic data for the Blue Creek Valley area and to provide a quantitative evaluation of the potential water-resources development of the area.

Utah