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Research about Colorado River

Source-linked reports with geographic coverage including Colorado River.

At least 91 records · Page 5Linked to original sources
USGS2002

Evaluation of airborne image data and LIDAR main stem data for monitoring physical resources within the Colorado River ecosystem

This study evaluated near-infrared LIDAR data acquired over the main-stem channel at four long-term monitoring sites within the Colorado River ecosystem (CRE) to determine the ability of these data to provide reliable indications in changes in water elevation over time. Our results indicate that there is a good correlation between the LIDAR water-surface elevations and ground measurements of water-edge elevation, but there are also inherent errors in the LIDAR data. The elevation errors amount to about 50 cm and therefore temporal changes in water-surface elevation that exceed this value by the majority of data at a particular location can be deemed significant or real. This study also evaluated airborne image data for producing photogrammetric elevation data and for automated mapping of sand bars and debris flows within the CRE. The photogrammetric analyses show that spatial resolutions of ≤ 10 cm are required to produce vertical accuracies < 20 cm and that digitally acquired data cannot yet support this monitoring requirement. The mapping analyses indicate that CIR image data are far superior to true-color and panchromatic image data in mapping sand bars and debris flows. The analyses also show that the CIR color information provide almost as much mapping capability as do the combination of CIR color and CIR image texture. Therefore, CIR image data should always be given preference in image data collections, not only for the physical resource program, but also for the biologic resource program.

Arizona↗
USGS2002

Standard errors of annual discharge and change in reservoir content data from selected stations in the lower Colorado River streamflow-gaging station network, 1995-99

The Bureau of Reclamation is currently (1995–2001) testing the Lower Colorado River Accounting System as a method to estimate the consumptive use of Colorado River water by diverters from Hoover Dam to Mexico. Consumptive use is estimated in the Lower Colorado River Accounting System method, in part, on the basis of the annual discharge or annual change in reservoir contents, as well as the variance of estimate of the annual discharge or the annual change in reservoir contents at several surface-water gaging stations in the lower Colorado River stream-gaging network. The standard error and the variance of estimate were determined for the annual discharge at 14 streamflow-gaging stations and for the annual change in content at 2 reservoir-content gaging stations used in the Lower Colorado River Accounting System for calendar years 1995–99. The standard error of the annual discharge was determined by using modifications to an existing method that assumes that the uncertainty in the discharge-rating shift is the main source of uncertainty in computed discharges and that the discharge-rating shift behaves as a first-order Markovian process. The method uses Kalman filtering of a first-order Markovian process as a statistical analogy to computing streamflow with a shifted discharge rating. Temporally unbiased residuals from a discharge rating are used as a surrogate for the actual shifts used to compute discharge. The standard error of the annual discharge is determined by using Kalman-filter theory and estimates of four parameters: (1) the measurement variance of the discharge measurements used to determine the discharge-rating shift, (2) the process variance of the discharge-rating residuals, (3) the serial correlation of the discharge-rating residuals, and (4) the frequency of the discharge measurements. The existing methodology was improved by estimating the measurement variance from a semivariogram of the discharge-rating residuals, rather than on the basis of empirically derived error estimates for discharge measurements. The process variance and serial correlation of the discharge-rating residuals are estimated from the semivariogram, rather than a variogram, of the discharge-rating residuals. The empirically derived estimates are based on characteristics of the discharge measurements such as number of depth and velocity observation sections, type of current meter, and bed material composition and stability. Measurement variance determined from the semivariograms was site specific and is therefore considered a better estimate than measurement variance determined from the empirically-derived estimates. The method of estimating the standard error of the annual discharge requires the assumption of unbiased discharge-rating residuals, and for this reason, the standard errors presented in this report only represent the random error in the annual discharge data. Estimates of the standard error of the annual change in reservoir content were determined on the basis of the reservoir-surface area and the standard error of reservoir-stage readings. The standard error of the annual discharge, as a percentage, ranged from 0.11 percent for the All- American Canal near Imperial Dam in 1998 to 12.3 percent for the Colorado River below Imperial Dam in 1996. The standard error of the annual discharge was less than 2 percent for all 5 years for 11 of the 14 streamflow-gaging stations. In terms of flow volume, the standard error of the annual discharge ranged from 97 acre-feet for the Mittry Lake Diversions in 1995 to 77,000 acre-feet for the Colorado River at the northerly international boundary with Mexico in 1998. In general, the standard error of the annual discharge, as a percentage, was smallest at streamflow-gaging stations on the main stem of the Colorado River; however, the standard error of the annual discharge in acre-feet was largest at these stations because of the large annual discharge on the main stem. The standard error of the annual change in content for the two reservoirs ranged from 1,590 acre-feet for Lake Havasu in 1996 to 2,790 acre-feet for Lake Mohave in 1995. The variance of estimate of the annual discharge for a streamflow-gaging station can be reduced by making additional discharge measurements; either by increasing the number of discharge measurements made per site visit, or by increasing the frequency of site visits. Measurement error can be reduced by using the average shift for two or more discharge measurements made during a site visit. For a streamflow-gaging station where measurement error is much greater than process error and the serial correlation of the discharge-rating residuals is high, an improved gaging strategy would involve making multiple discharge measurements per site visit. In contrast, for a streamflow-gaging station where process error is much greater than measurement error and the serial correlation of discharge-rating residuals is low, the gaging strategy would consist of several single discharge-measurement site visits. For a given operating cost or for a given variance of estimate of the annual discharge at a streamflow-gaging station, the optimal site-visit and discharge-measurement strategy can be determined, providing that the travel costs as well as the measurement variance, process variance, and serial correlation of discharge-rating residuals are known.

Arizona;California↗
USGS2002

Lost, a desert river and its native fishes: A historical perspective of the lower Colorado River

The Colorado River had one of the most unique fish communities in the world. Seventy-five percent of those species were found no where else in the world. Settlement of the lower basin brought dramatic changes to both the river and its native fish. Those changes began more than 120 years ago as settlers began stocking nonnative fishes. By 1930, nonnative fish had spread throughout the lower basin and replaced native communities. All resemblance of historic river conditions faded with the construction of Hoover Dam in 1935 and other large water development projects. Today, few remember what the Colorado River was really like. Seven of the nine mainstream fishes are now federally protected as endangered. Federal and state agencies are attempting to recover these fish; however, progress has been frustrated due to the severity of human impact. This report presents testimony, old descriptions, and photographs describing the changes that have taken place in hopes that it will provide managers, biologists, and the interested public a better appreciation of the environment that shaped these unique fish.

Colorado River↗
USGS2000

Identifying wells downstream from Laguna Dam that yield water that will be replaced by water from the Colorado River, Arizona and California

This report summarizes a comprehensive study and development of the method documented in Owen-Joyce and others (2000). That report and one for the area upstream from Laguna Dam (Wilson and Owen-Joyce, 1994) document the accounting-surface method to identify wells that yield water that will be replaced by water from the Colorado River. Downstream from Laguna Dam, the Colorado River is the source for nearly all recharge to the river aquifer. The complex surface-water and ground-water system that exists in the area is, in part, the result of more than 100 years of water-resources development. Agriculture is the principal economy and is possible only with irrigation. The construction and operation of canals provides the means to divert and distribute Colorado River water to irrigate agricultural lands on the flood plains and mesas along the Colorado and Gila Rivers, in Imperial and Coachella Valleys, and in the area upstream from Dome along the Gila River. Water is withdrawn from wells for irrigation, dewatering, and domestic use. The area downstream from Laguna Dam borders additional areas of agricultural development in Mexico where Colorado River water also is diverted for irrigation.

Arizona;California↗
USGS1998

Peak-flow frequency for tributaries of the Colorado River downstream of Austin, Texas

A procedure to estimate the peak discharge associated with large floods is needed for tributaries of the Colorado River downstream of Austin, Texas, so that appropriate peak discharges can be used to estimate floodplain boundaries and used for the design of bridges and other structures. The U.S. Geological Survey, in cooperation with the Lower Colorado River Authority, studied flood peaks for streams in all or parts of 22 counties in that part of the Colorado River Basin extending downstream of Town Lake in Austin to the Gulf of Mexico. The study area was selected because the streams in this area either are tributaries to the Colorado River or have flood characteristics similar to those tributaries. Peak-flow frequency for 38 stations with at least 8 years of data in natural (unregulated and nonurbanized) basins was estimated on the basis of annual peak-streamflow data through water year 1995. Peak-flow frequency represents the peak discharges for recurrence intervals of 2, 5, 10, 25, 50, 100, 250, and 500 years. The peak-flow frequency and drainage basin characteristics for the stations were used to develop two sets of regression equations to estimate peak-flow frequency for tributaries of the Colorado River in the study area. One set of equations was developed for contributing drainage areas less than 32 square miles, and another set was developed for contributing drainage areas greater than 32 square miles. A procedure is presented to estimate the peak discharge at sites where both sets of equations are considered applicable. Additionally, procedures are presented to compute the 50-, 67-, and 90-percent prediction interval for any estimation from the equations.

Texas↗
USGS1991

Low-flow sediment transport in the Colorado River

In support of beach-stability research, bedload and suspended sediment were measured during a steady flow of 5,880 ft 3 /s and receding flows from 12,100 to 5,660 ft 3 /s in the Colorado River above National Canyon, near Supai, Arizona, October 7-12, 1989. During steady flows, 75 percent of the mean total-sediment discharge of 128 t/d was in suspension and about half the total-sediement load was finer than 0.062 mm. Median grain sizes of bedload and bed material were 0.43 and 0.40 mm, respecively. Although steady-flow bedload transport varied from the mean by about 45 percent, suspended-sediment discharge remained constant within sampling error. Helley-Smith and BL-86-3 bedload samplers were not significantly different. At larger transport rates, however, the rates measured by the Helley-Smith exceeded those measure by the BL-86-3. Transport rates from bedload samples collected with Helley-Smith and BL-86-3 bedload samplers in sections 8 ft apart demonstrate no consistent autocorrelation or cross correlation. Cross-sectional bedload-transport rates measured concurrently or consecutively with the bedload samplers showed good agreement indicating that bedload varied by at least a factor of 2.4 during the steady-flow period. Ninety-five percent of the bedload transport during low flow occurred in the center one-third of the channel.

Arizona↗
USGS1980

Sediment and water discharge of the Colorado River at Matagorda, Texas: May 4-7, and June 7-11, 1979

The U.S. Army Corps of Engineers requested the U.S. Geological Survey to collect data on the Colorado River at Matagorda, Texas , to determine the total sediment discharge into Matagorda Bay if all the water from the Colorado River were diverted into the bay. Data were collected from two floods (May 4-7, and June 7-11 , 1979) with peak discharges of 24,900 cubic feet per second and 40,900 cubic feet per second. The total suspended-sediment discharge from the first flood was approximately 201,000 tons, and the total suspended-sediment discharge from the second flood was 630,000 tons. The volume of sediment from these two floods was approximately 970 acre-feet with approximately 20 acre-feet of this total being the bed load. (USGS)

Texas↗
USGS1969

The Colorado River region and John Wesley Powell

A century ago John Wesley Powell-teacher, scientist, and veteran of the Civil War-set out to explore the unknown reaches of the Colorado River. He emerged from the forbidding canyons with a compelling interest in the nature of the western lands and how they could be developed for the greatest benefit to the Nation. A man gifted with imagination, yet always tempered by the scientist's appreciation for facts, Powell became one of the country's most vigorous proponents for the orderly development of the public domain and the wise use of its natural resources. Throughout his lifetime, Powell stood firm in his belief that science, as a sound basis for human progress, should serve all the people, and he played an important role in organizing and directing scientific activities of the U.S. Government. His zeal led to the establishment of the Geological Survey in the U.S. Department of the Interior and the Bureau of Ethnology in the Smithsonian Institution. On this 100th Anniversary of the Powell Colorado River Expedition, the U.S. Department of the Interior, Smithsonian Institution, and National Geographic Society (which Powell helped to found) have joined many organizations and individuals to recall the works of this man ;and to examine anew the imprints of his mind. His prescient concepts for the Nation's programs concerning people and their environment have been enhanced through a century of national development.

Colorado River↗
USGS1969

John Wesley Powell: Pioneer statesman of federal science

In the middle decades of the 19th century, American science matured rather rapidly. The general scholar with an interest in natural history gave place to the specialist in a particular science, and the various sciences themselves became distinct from each other and from the general body of knowledge. The geological sciences made especially rapid progress in America because of the opportunity and the necessity to explore the vast western territories. Although Clarence King later remarked 1 that before 1867 (when Congress authorized both the Geological Exploration of the Fortieth Parallel and the Geological and Geographical Survey of the Territories) "geology was made to act as a sort of camp-follower to expeditions whose main object was topographic reconnoissance," and that it amounted to "little more than a slight sketch of the character and distribution of formations, valuable chiefly as indicating the field for future inquiry," American geologists had, in fact, established a professional society, the Association of American Geologists, as early as 1840. Several years later this society became the American Association for the Advancement of Science. Several State surveys were founded in the 1830's, and by 1840, courses in geology were regularly included in the curricula of several colleges.

Colorado River↗
USGS1969

Geologic history of the Colorado River

John Wesley Powell clearly recognized that the spectacular features of the Colorado River - its many grand canyons - were dependent upon the structural history of the mountainous barriers crossed by the river. He conceived of three different historical relationships between rivers and structural features: (1) Newly uplifted land surfaces have rivers that flow down the initial slope of the uplift; these relationships he termed consequent. (2) A river may be older than an uplift that it crosses because it has been able to maintain its course by eroding downward as the uplift progresses; this relationship he named antecedent. (3) An uplifted block may have been buried by younger deposits upon which a river becomes established. The river, in cutting downward, uncovers the uplifted block and becomes incised into it; this relationship he called superimposed. The geologic history of the Colorado River involves all three relationships. In addition, although the position of the river course through a particular structural barrier may have been the result of superposition, the depth of the canyon at that point may be largely due to renewed uplift of the barrier; such deepening of the canyon, therefore, is due to antecedence. The problem of the Colorado River remains today very much as G. K. Gilbert stated it nearly 100 years ago: "How much is antecedent and how much is superimposed?" The question must be asked separately for each stretch of the river.

Colorado River↗
USGS1955

Quality of water of the Colorado River, 1925-40

The study of the quality of water of the Colorado River and its tributaries has been a continuing one since 1925. The data so obtained have been useful in the planning and construction of dams and reservoirs, the utilization of the water within the basin, and in planning the economy of areas outside of the basin, partially or wholly dependent on the diversion or importation of water from the Colorado River or its tributaries. Much chemical quality data of the Colorado River and its tributaries collected during the period from 1925 to 1940 have not been published in detail. The purpose of this report is to make available for consultation and ready reference those previously unpublished data collected for the period 1925 to 1940, mainly between 1930 and 1940. Included among these data are many detailed chemical analyses of composites of daily samples and single samples of the Colorado River and its main tributaries and less detailed analyses of many other samples. In a few instances, for continuity of the record, analyses are included that have been published in Survey reports. Discussions of the quality of water of the Colorado River basin either in published reports or in mimeograph form are available; therefore, this report will include only tabulated data. Data obtained for the period 1925 to 1930 for the most part were published in three Geological Survey Water-Supply Papers, 596-B, 636-A, and 638-D, all out of print. Summary data for the streams in the Colorado River basin for the period 1925 to 1943 were published in U.S. Geological Survey Water-Supply Paper 970, "Quality of surface waters of the United States, 1943". These summaries consist mainly of annual weighted averages of chemical analyses, dissolved-solids loads, and extremes of dissolved solids and hardness. Analyses of samples from Lake Mead are available in a series of reports, "Lake Mead Density Currents Investigations", by the Bureau of Reclamation /1937 -1940, Vols. I and ll; 1940 -1946; Vol. III/. Data on the suspended sediment in the Colorado River for the period 1925-1941 were published in 1947, in U.S. Geological Survey Water -Supply Paper 998. Since 1940 results of water-quality investigations in the Colorado River basin have been published in the annual U.S. Geological Survey reports, "Quality of surface waters of the United States".

Colorado River↗
USGS1947

Suspended sediment in the Colorado River, 1925-41

This report gives the results of sediment-sampling studies of the Geological Survey in the Colorado River basin for the period from October 1, 1925, to September 30, 1941. Records are given for the entire period for the Grand Canyon gaging station and for shorter periods at other stations in the basin. The results reported consist of the records of the mean daily concentrations.of sediment for all stations, and in addition, the mean daily discharge and daily load of sediment for many of the stations. The available records indicate that the runoff of the Colorado near Cisco, Utah, plus the runoff of the Green at Green River, Utah, plus the runoff of the San Juan near Bluff, Utah, amount to about 90 percent of the runoff at the Grand Canyon gaging station, but the sediment loads at the three upper stations amount to only about 60 percent of the sediment load at Grand Canyon. The Little Colorado River and two or three other unsampled tributaries probably are the major sources of the unmeasured sediment Information is given concerning the sizes of the particles of the sediment at the Grand Canyon, Willow Beach, and Bluff stations during periods of this investigation. The annual load at Grand Canyon during the 16 years ranged from 50,080,000 tons in 1933-34 to 480,000,000 tons in 1928-29, and the mean annual load at that station for the 16-year period was 200,200,000 tons. The mean annual runoff for the Grand Canyon station during the period was 12,640,000 acre-feet

Colorado River↗