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An accounting procedure is developed which determines a flow regime that is capable of transporting an amount of bedload sediment necessary to ensure channel stability downstream. The method allows for sediment buildup in the channel within geomorphic threshold limits during low flow periods. During periods of high runoff, enough water is bypassed to transport the stored sediment. The procedure utilizes only those flows of sufficient magnitude to maintain channel stability over the long run (25–50+ years). An example is presented which determines the volume of water and frequency of release for channel maintenance purposes downstream from a hypothetical water diversion project. Of some 1,200,000 acre feet generated...
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The 1935 images were obtained as digitally scanned versions of aerial photographs acquired by the U.S. Department of Agriculture at a scale of 1:31,680. The actual date of image acquisition is not known. The images were previously scanned at 600 dpi to produce a nominal pixel size of 1.28 m (Friedman et al., 2015). The images were registered and rectified using identifiable common points from the 1996 DOQQs. See description of positional accuracy below. Data derived from features mapped from the 1935 images were presented in: Friedman, J.M., Vincent, K.R., Griffin, E.R., Scott, M.L., Shafroth, P.B., and Auble, G.T., 2015, Processes of arroyo filling in northern New Mexico, USA, GSA Bulletin, 127(3/4), 621-640....
Efforts to conserve stream and river biota could benefit from tools that allow managers to evaluate landscape-scale changes in species distributions in response to water management decisions. We present a framework and methods for integrating hydrology, geographic context and metapopulation processes to simulate effects of changes in streamflow on fish occupancy dynamics across a landscape of interconnected stream segments. We illustrate this approach using a 482 km2 catchment in the southeastern US supporting 50 or more stream fish species. A spatially distributed, deterministic and physically based hydrologic model is used to simulate daily streamflow for sub-basins composing the catchment. We use geographic data...
A substantial increase in fluvial sediment supply relative to transport capacity causes complex, large-magnitude changes in river and floodplain morphology downstream. Although sedimentary and geomorphic responses to sediment pulses are a fundamental part of landscape evolution, few opportunities exist to quantify those processes over field scales. We investigated the downstream effects of sediment released during the largest dam removal in history, on the Elwha River, Washington, USA, by measuring changes in riverbed elevation and topography, bed sediment grain size, and channel planform as two dams were removed in stages over two years. As 10.5 million t (7.1 million m3) of sediment was released from two former...
The NYCDEP Stream Management Program (SMP) is responsible for developing stream management plans for NYC water supply watersheds in the Catskill Mountains, New York State. This mostly forested region of Pleistocene glacial deposits over sedimentary rocks ranges in elevation from approximately 600 to 4,120 feet above sea level; average annual precipitation ranges from 36 to >60 inches/year. The SMP uses fluvial geomorphology as a framework for stream assessment, restoration and monitoring. Bankfull discharge, a common surrogate for channel forming discharge, forms a basis for assessing and classifying stream morphology (Rosgen, 1994). The SMP documented bankfull discharge and associated stream geometry for 41 cross...
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The 1970s images were obtained as digital scans on CDs, with no metadata. Source information for the original aerial photographs is not available. Original photo scale was about 1:40,000 for the 1975 images (filenames beginning "r75")and 1:12,000 for the 1979 images (filenames beginning "rfl"). I registered and rectified these images using identifiable common points from 1996 DOQQs. See the description of positional accuracy below. Data derived from features mapped from the 1970s images were presented in: Friedman, J.M., Vincent, K.R., Griffin, E.R., Scott, M.L., Shafroth, P.B., and Auble, G.T., 2015, Processes of arroyo filling in northern New Mexico, USA, GSA Bulletin, 127(3/4), 621-640. doi: 10.1130/B31046.1
Seismic signals near rivers are partially composed of the elastic waves generated by bedload particles impacting the river bed. In this study, we explore the relationship between this seismic signal and river bedload transport by analyzing high-frequency broadband seismic data from multiple stations along the Chijiawan River in northern Taiwan following the removal of a 13 m check dam. This dam removal provides a natural experiment in which rapid and predictable changes in the river's profile occur, which in turn enables independent constraints on spatial and temporal variation in bedload sediment transport. We compare floods of similar magnitudes with and without bedload transport, and find that the amplitude of...
We present herein clear field evidence for the persistence of a coarse surface layer in a gravel-bed river during flows capable of transporting all grain sizes present on the channel bed. Detailed field measurements of channel topography and bed surface grain size were made in a gravel-bed reach of the Colorado River prior to a flood in 2003. Runoff produced during the 2003 snowmelt was far above average, resulting in a sustained period of high flow with a peak discharge of 27 m3/s (170% of normal peak flow); all available grain sizes within the study reach were mobilized in this period of time. During the 2003 peak flow, the river avulsed immediately upstream of the study reach, thereby abandoning approximately...
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1996 georeferenced aerial photographs cover the lower Rio Puerco from the confluence with the Rio San Jose 70 km down-valley to the confluence with the Rio Grande. The images were obtained from enlargements of 1:40,000 scale National Aerial Photography Program (NAPP) photographs printed from negatives at a scale of 1:5,000, then scanned at 600 dpi. Pixel size of the raster images is about 0.22 m, compared to the DOQQs, which have 1-m pixel size. The segments were registered and rectified in ArcINFO using common points from USGS DOQQs published in 1999, which were derived from the same 1996 NAPP photo set, with terrain corrections from a 1-degree DEM applied. Registration points were typically center of mass of small...
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Geomorphic features mapped from historical aerial photographs (1935, 1950s, 1970s, and 1996), satellite imagery (November 2006), and digital aerial imagery (Standard Imagery LiDAR Composite; Spectrum Mapping, LLC, 2005) are provided in shapefiles for each year of data. Features mapped are tops of the arroyo walls, edges of the arroyo bottom (covering the active floodplain and channel), tops of channel banks, the channel centerline, canopy cover, and 2006 flood sand deposits. In addition, shapefiles containing a reference arroyo centerline, points at 0.5-km intervals along the arroyo centerline, and polygons identifying the 0.5-km arroyo segments are provided. Individual metadata files describe the contents of each...
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The 1950s images were downloaded from Earth Explorer as medium-resolution scans of aerial photographs, with pixel size ranging from 1.33 to 2.32 m. Original photo scales were 1:54,000 or 1:20,000. (See Source Citation below.) I registered and rectified these images using identifiable common points from 1996 DOQQs. Images with filenames beginning "r37" were acquired 11-29-1953. Images with filenames beginning "r43" were acquired 01-31-1954. Image r1954r49_6786.tif was acquired 02-03-1954. Remaining images have the date of acquisition in the filename, starting with the format "ryymmdd...". Data derived from features mapped from the 1950s images were presented in: Friedman, J.M., Vincent, K.R., Griffin, E.R., Scott,...
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A long-term study of the geomorphic history of the lower Rio Puerco arroyo in north-central New Mexico included the collection of high-precision (Real-time kinematic) GPS survey data (2002, 2007, 2010, and 2014), registration and rectification of historical aerial photographs (1935, 1950s, 1970s, and 1996), an aerial LiDAR survey (2005) with collection of digital imagery, and acquisition of post-flood (2006) satellite imagery. The Rio Puerco is a single-thread, meandering stream inset within an arroyo located in semiarid north-central New Mexico. The study reach extent is from the confluence with the Rio San Jose 67 km downvalley to the Rio Puerco streamgage near Bernardo, NM. Arroyo and channel geomorphic features...
The hydrology and geomorphology of large rivers in America reflect the pervasive influence of an extensive water control infrastructure including more than 75,000 dams. One hundred thirty-seven of the very large dams, each storing 1.2 km3 (106 acre feet) of water or more, alter the flows of every large river in the country. The hydrologic effects of these very large dams emerge from an analysis of the stream gage records of 72 river reaches organized into 36 pairs. One member of each pair is an unregulated reach above a dam, whereas the other is a regulated reach downstream from the same structure. Comparison of the regulated and unregulated reaches shows that very large dams, on average, reduce annual peak discharges...
Many ephemeral streams in western North America flowed over smooth valley floors before transformation from shallow discontinuous channels into deep arroyos. These inherently unstable streams of semiarid regions are sensitive to short-term climatic changes, and to human impacts, because hillslopes supply abundant sediment to infrequent large streamflow events. Discontinuous ephemeral streams appear to be constantly changing as they alternate between two primary modes of operation; either aggradation or degradation may become dominant. Attainment of equilibrium conditions is brief. Disequilibrium is promoted by channel entrenchment that causes the fall of local base level, and by deposition of channel fans that causes...
American geomorphologic research related to dams is embedded in a complicated context of science, policy, economics, and culture. Research into the downstream effects of large dams has progressed to the point of theory-building, but generalization and theory-building are from this research because (1) it is highly focused on a few locations, (2) it concerns mostly very large dams rather than a representative sample of sizes, (3) the available record of effects is too short to inform us on long-term changes, (4) the reversibility of changes imposed by dam installation and operation is unknown, and (5) coordinated funding for the needed research is scarce. In the scientific context, present research is embedded in...
A regional synthesis of paleoflood chronologies on rivers in Arizona and southern Utah reveals that the largest floods over the last 5000 years cluster into distinct time periods that are related to regional and global climatic fluctuations. The flood chronologies were constructed using fine-grained slackwater deposits that accumulate in protected areas along the margins of bedrock canyons and selectively preserve evidence of the largest events. High-magnitude floods were frequent on rivers throughout the region from 5000 to 360014C yrs BP (dendrocalibrated age = 3800-2200 BC) and increased again after 2200 BP (400 BC), with particularly prominent peaks in magnitude and frequency around 1100-900 BP (AD 900?1100)...
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Accelerometer scour monitors were deployed on the Cedar River, Washington from 2013 to 2014 as part of a study on the timing of streambed scour at 73 locations in salmon-spawning habitat. This data release contains data of the three-dimensional orientation recorded at 20- to 30-minute intervals for the 46 accelerometer monitors that were recovered in 2014. Each accelerometer scour monitor was comprised of three individual accelerometers that were deployed in a vertical profile within the streambed.
Analysis of field data and development and application of a dynamic model indicate that the processes that control the number and distribution of age-0 Colorado pikeminnow in the middle Green River are poorly understood. Colorado pikeminnow are a federally endangered species endemic to the Colorado River basin that utilize backwaters during their larval stage. The present agency-mandated field sampling program for backwater habitats may be inadequate because it takes place at a time when the model predicts that most larval fish have drifted beyond the study area. The model predicts that water releases from Flaming Gorge Dam have a large potential effect on larval drift, because high releases at the time of drift...
Billions of dollars are being spent in the United States to restore rivers to a desired, yet often unknown, reference condition. In lieu of a known reference, practitioners typically assume the paradigm of a connected watercourse. Geological and ecological processes, however, create patchy and discontinuous fluvial systems. One of these processes, dam building by North American beavers (Castor canadensis), generated discontinuities throughout precolonial river systems of northern North America. Under modern conditions, beaver dams create dynamic sequences of ponds and wet meadows among free-flowing segments. One beaver impoundment alone can exceed 1000 meters along the river, flood the valley laterally, and fundamentally...
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Dr. Richard Janda of the USGS began a channel monitoring program in Redwood Creek in northern coastal California in 1973. The USGS continued this work through 2013, when the Research Geologist, Dr. Mary Madej retired. This effort produced 40 years of channel change data in rivers that were disrupted by severe erosion following timber harvest of old-growth redwood forests, a portion of the program's data (plus 1953 data) has been preserved in this data release. Original field surveys documented bank erosion, aggradation, and degradation at 60 cross-sectional transects at annual or biannual timesteps. Three river reaches also have long-term longitudinal channel bed surveys which document the distribution and development...
map background search result map search result map Lower Rio Puerco geospatial data, 1935 - 2014 Lower Rio Puerco mapped geomorphic features (shapefiles), 1935, 1950s, 1970s, 1996, 2005, and 2006 Lower Rio Puerco 1935 georeferenced aerial photographs Lower Rio Puerco 1950s georeferenced aerial photographs Lower Rio Puerco 1970s georeferenced aerial photographs Lower Rio Puerco 1996 georeferenced NAPP photo segments River Channel Survey Data, Redwood Creek, California, 1953-2013 Accelerometer scour monitor data on the Cedar River, Washington, 2013 - 2014 Accelerometer scour monitor data on the Cedar River, Washington, 2013 - 2014 Lower Rio Puerco 1970s georeferenced aerial photographs Lower Rio Puerco 1935 georeferenced aerial photographs Lower Rio Puerco geospatial data, 1935 - 2014 Lower Rio Puerco mapped geomorphic features (shapefiles), 1935, 1950s, 1970s, 1996, 2005, and 2006 Lower Rio Puerco 1950s georeferenced aerial photographs Lower Rio Puerco 1996 georeferenced NAPP photo segments River Channel Survey Data, Redwood Creek, California, 1953-2013