Glen Canyon Dam has altered flow and fine sediment (sand, silt, and clay) dynamics of the Colorado River in Grand Canyon. Before the dam, the Colorado River experienced highly variable flows and carried a large amount of sediment through Grand Canyon, which maintained sandbars (highly valued camping areas in Grand Canyon) and provided sand that protected archeological and cultural sites from damaging erosion. Since completion of the dam in 1963, relatively little sediment is carried into Grand Canyon. This, coupled with an increase in average daily flows and daily flow fluctuations for power generation have caused sandbar erosion. To manage limited sand resources in Grand Canyon, experimental high flows, which are much higher than base-operations flows, are periodically conducted. High-flow experiments are designed to determine if limited sediment resources can be managed to maintain or increase sandbar size. The Grand Canyon Monitoring and Research Center, part of the Southwest Biological Science Center, conducts monitoring and research studies of these experimental flows.
Background
The Colorado River is one of the longest rivers in the United States with its origins in the Rocky Mountains of the western United States. Historically, the river flowed into the Gulf of California; however, due to the network of dams and water diversions constructed on the Colorado River and its tributaries, it now rarely reaches the gulf. One of those dams is Glen Canyon Dam which is located near Page, Arizona. Glen Canyon Dam construction was completed in 1963 and Lake Powell, the reservoir created by the dam, took about 17 years to completely fill. The dam and reservoir serve several purposes including water storage, flood control, generating hydroelectric power, and providing recreational opportunities. Glen Canyon Dam has altered the dynamics of the Colorado River in Grand Canyon, including the variables that influence sandbars—river flow and fine sediment (sand, silt, and clay) supply and transport. To address this, high-flow experiments are periodically conducted.
A high-flow experiment is a release of water from Glen Canyon Dam that is much larger than the base flow that is normally released. This type of experimental flow is conducted specifically to mobilize sand from the bottom of the Colorado River to rebuild sandbars and beaches in Grand Canyon, and they generally last for several days. An additional, and important function of this type of experiment is to provide opportunities to study sandbar development in the Colorado River and sand movement in the river and surrounding landscape within Glen Canyon (directly downstream of Glen Canyon Dam and part of Glen Canyon National Recreation Area) and Grand Canyon (including in Grand Canyon National Park). The information gained from these experiments provide Grand Canyon National Park managers the information they need to make appropriate decisions about the park’s resources. The Grand Canyon Monitoring and Research Center, part of the Southwest Biological Science Center, conducts much of the science associated with high-flow experiments and its scientists are experts in river-based and land-based sediment movement.
Why are High-Flow Experiments Done? The Colorado River in Grand Canyon Before and After Glen Canyon Dam.
Glen Canyon Dam has influenced many aspects of the Colorado River; however, the changes to the river’s sand dynamics are the primary reason for conducting high-flow experiments. Before the dam was constructed, the Colorado River would transport large amounts of fine sediment downstream through Grand Canyon. Some would be deposited on the bed of the river, and during floods, sand would be deposited on sandbars and beaches on the margins of the river above levels of base flow. Most of that sediment now accumulates in Lake Powell instead of being transported downstream. The Colorado River downstream of the dam now transports less than 5-20% of the sand it historically transported. Most of sand inputs now come from the Paria River, approximately 17 river miles downstream of Glen Canyon Dam, and the Little Colorado River, approximately 75 miles downstream of the dam. Both tributaries only contribute significant amounts of sediment to the Colorado River during large precipitation events.
In addition to limiting sand supply, Glen Canyon Dam has dramatically altered the flow of the Colorado River. Before the dam, the Colorado River experienced large spring snowmelt floods that were commonly 71,000 cubic feet per second (about 530,000 gallons per second) or larger, with the largest flood on record reaching approximately 210,000 cubic feet per second (about 1,571,000 gallons per second) in June 1884. During other parts of the year, the flows could be very low with the lowest flow recorded at 1,095 cubic feet per second (about 8,200 gallons per second) in August 1934. Now, daily flows of the Colorado River are largely determined by hydroelectric power generation needs and varies between about 8,000-17,000 cubic feet per second (about 60,000-127,000 gallons per second) depending on the time of day, month, and season. Therefore, before Glen Canyon Dam, the Colorado River experienced much higher flood flows and much lower base flows than it does today, and these changes have influenced sand dynamics in Grand Canyon.
In addition to transporting and depositing large amounts of sand, Colorado River floods prior to Glen Canyon Dam would strip vegetation off sandbars. During low flow periods, much of the sand deposited on sandbars and on the channel bottom became exposed. Wind would transport sand from those areas to sand dune fields. Many sand dune fields in Grand Canyon contain or are near important archaeological and cultural sites. Sand can provide protective cover to these sites which are otherwise prone to natural gully erosion processes caused by runoff during intense rainstorms that are common during the annual late-summer monsoon season in Grand Canyon.
The regulated flows of the modern-day Colorado River in Grand Canyon, combined with the greatly diminished sand supply, are not favorable for building or maintaining sandbars. Therefore, without high-flow events sandbars are slowly decreasing in size due to erosion. In addition, regulated flows of the modern river have caused dense stands of vegetation to encroach onto bare sand surfaces, decreasing the amount of area available for campsites in Grand Canyon. Approximately 25,000 recreationists per year travel through Grand Canyon on the Colorado River or hike to the river, and sandbar campsites are an important part of that experience. Additionally, the expansion of riparian vegetation onto otherwise bare sand limits the amount of sand that can be blown from sandbars onto sand dune fields and fill erosional gullies. This has allowed some erosional processes to negatively affect archaeological sites and many of these sites are in danger of being damaged or lost.
High-Flow Experiments
High-flow experiments are conducted when enough sediment from tributaries has been deposited on the bed of the Colorado River such that sand can be mobilized to increase the size of sandbars along the margin of the river in Grand Canyon without transporting out more sand than was present prior to the tributary inputs. This occurs by allowing much larger volumes of water through Glen Canyon Dam for a few days, which transports sand from the river channel to sandbars and beaches. High-flow experiments result in water flows much higher than the typical base-operations flows from Glen Canyon Dam, with between 31,500-45,000 cubic feet per second (about 236,000-337,000 gallons per second) released during the experiments. Although these flows are approximately half the magnitude and a fraction of the duration of the average spring snowmelt floods that occurred prior to Glen Canyon Dam, high-flow experiments can increase the size of sandbars in Grand Canyon. However, because the river’s modern-day flows erode sandbars over time, it is necessary to repeat high-flow experiments to maintain sandbars that erode during base operations. Monitoring results also suggest that there are cumulative effects of sand resupply to dune fields when annual high-flow experiments are conducted consistently in consecutive years. High-flow experiments have been conducted in 1996, 2004, 2008, 2012, 2013, 2014, 2016, and 2018 (November 5-8). Grand Canyon Monitoring and Research Center scientists continue to monitor the effects of these high-flow experiments and provide that information to resource managers and decision makers so they can make informed decisions about managing the resources of Grand Canyon.
Below are other science projects associated with this project.
River Sediment Dynamics
River Geomorphology and Geomorphic Change
Sediment Storage in Grand Canyon
River Campsites in Grand Canyon National Park
Terrestrial Riparian Vegetation Monitoring: How One Square Meter Can Tell the Story of 245 River Miles
Overview of Riparian Vegetation in Grand Canyon
Connectivity of Sand Resources Along the Colorado River in Grand Canyon
Grand Canyon Sandbar Monitoring
Below are publications associated with this project.
Quantifying geomorphic and vegetation change at sandbar campsites in response to flow regulation and controlled floods, Grand Canyon National Park, Arizona
Geomorphology and vegetation change at Colorado River campsites, Marble and Grand Canyons, Arizona
Automated remote cameras for monitoring alluvial sandbars on the Colorado River in Grand Canyon, Arizona
Variability in eddy sandbar dynamics during two decades of controlled flooding of the Colorado River in the Grand Canyon
Riparian vegetation, Colorado River, and climate: five decades of spatiotemporal dynamics in the Grand Canyon with river regulation
Building sandbars in the Grand Canyon
Do management actions to restore rare habitat benefit native fish conservation? Distribution of juvenile native fish among shoreline habitats of the Colorado River
The influence of controlled floods on fine sediment storage in debris fan-affected canyons of the Colorado River basin
Food-web dynamics in a large river discontinuum
Estimating recruitment dynamics and movement of rainbow trout (Oncorhynchus mykiss) in the Colorado River in Grand Canyon using an integrated assessment model
Ecosystem ecology meets adaptive management: food web response to a controlled flood on the Colorado River, Glen Canyon
Effects of fluctuating flows and a controlled flood on incubation success and early survival rates and growth of age-0 rainbow trout in a large regulated river
Below are data or web applications associated with this project.
Predicted Shorelines for High Flows on the Colorado River Application
This application highlights modeled flows of the Colorado River for a discharge of 41,000 cubic feet per second (cfs) that is approximate to recent (2012 - 2018) and future anticipated water releases associated with a High Flow Experiments conducted from Glen Canyon Dam near Page, Arizona. These data are to help visualize the water levels during High Flow Events in relation to othe
APPLICATION - Discharge, Sediment, and Water Quality Monitoring Application
This link launches the Grand Canyon Monitoring and Research Center’s discharge, sediment and water quality monitoring application gateway. Sediment and water quality information can be accessed from here for our on-going monitoring taking place across the Southwest U.S.
APPLICATION - Grand Canyon Sandbar Monitoring
Several applications related to the Grand Canyon Monitoring and Research Center’s long-term sandbar monitoring project can be accessed here, including the sandbar area and volume tool and applications highlighting changes to sandbars as a result of High-Flow Events (HFEs) conducted by Glen Canyon Dam near Page, Arizona.
Below are partners associated with this project.
- Overview
Glen Canyon Dam has altered flow and fine sediment (sand, silt, and clay) dynamics of the Colorado River in Grand Canyon. Before the dam, the Colorado River experienced highly variable flows and carried a large amount of sediment through Grand Canyon, which maintained sandbars (highly valued camping areas in Grand Canyon) and provided sand that protected archeological and cultural sites from damaging erosion. Since completion of the dam in 1963, relatively little sediment is carried into Grand Canyon. This, coupled with an increase in average daily flows and daily flow fluctuations for power generation have caused sandbar erosion. To manage limited sand resources in Grand Canyon, experimental high flows, which are much higher than base-operations flows, are periodically conducted. High-flow experiments are designed to determine if limited sediment resources can be managed to maintain or increase sandbar size. The Grand Canyon Monitoring and Research Center, part of the Southwest Biological Science Center, conducts monitoring and research studies of these experimental flows.
Background
A view of Glen Canyon Dam from the Colorado River. (Credit: Todd Wojtowicz, USGS, Southwest Biological Science Center. Public domain.) The Colorado River is one of the longest rivers in the United States with its origins in the Rocky Mountains of the western United States. Historically, the river flowed into the Gulf of California; however, due to the network of dams and water diversions constructed on the Colorado River and its tributaries, it now rarely reaches the gulf. One of those dams is Glen Canyon Dam which is located near Page, Arizona. Glen Canyon Dam construction was completed in 1963 and Lake Powell, the reservoir created by the dam, took about 17 years to completely fill. The dam and reservoir serve several purposes including water storage, flood control, generating hydroelectric power, and providing recreational opportunities. Glen Canyon Dam has altered the dynamics of the Colorado River in Grand Canyon, including the variables that influence sandbars—river flow and fine sediment (sand, silt, and clay) supply and transport. To address this, high-flow experiments are periodically conducted.
A high-flow experiment is a release of water from Glen Canyon Dam that is much larger than the base flow that is normally released. This type of experimental flow is conducted specifically to mobilize sand from the bottom of the Colorado River to rebuild sandbars and beaches in Grand Canyon, and they generally last for several days. An additional, and important function of this type of experiment is to provide opportunities to study sandbar development in the Colorado River and sand movement in the river and surrounding landscape within Glen Canyon (directly downstream of Glen Canyon Dam and part of Glen Canyon National Recreation Area) and Grand Canyon (including in Grand Canyon National Park). The information gained from these experiments provide Grand Canyon National Park managers the information they need to make appropriate decisions about the park’s resources. The Grand Canyon Monitoring and Research Center, part of the Southwest Biological Science Center, conducts much of the science associated with high-flow experiments and its scientists are experts in river-based and land-based sediment movement.
Why are High-Flow Experiments Done? The Colorado River in Grand Canyon Before and After Glen Canyon Dam.
Glen Canyon Dam has influenced many aspects of the Colorado River; however, the changes to the river’s sand dynamics are the primary reason for conducting high-flow experiments. Before the dam was constructed, the Colorado River would transport large amounts of fine sediment downstream through Grand Canyon. Some would be deposited on the bed of the river, and during floods, sand would be deposited on sandbars and beaches on the margins of the river above levels of base flow. Most of that sediment now accumulates in Lake Powell instead of being transported downstream. The Colorado River downstream of the dam now transports less than 5-20% of the sand it historically transported. Most of sand inputs now come from the Paria River, approximately 17 river miles downstream of Glen Canyon Dam, and the Little Colorado River, approximately 75 miles downstream of the dam. Both tributaries only contribute significant amounts of sediment to the Colorado River during large precipitation events.
Sandbar on the Colorado River in Grand Canyon being used as a camping spot. (Credit: Scott VanderKooi, USGS. ) In addition to limiting sand supply, Glen Canyon Dam has dramatically altered the flow of the Colorado River. Before the dam, the Colorado River experienced large spring snowmelt floods that were commonly 71,000 cubic feet per second (about 530,000 gallons per second) or larger, with the largest flood on record reaching approximately 210,000 cubic feet per second (about 1,571,000 gallons per second) in June 1884. During other parts of the year, the flows could be very low with the lowest flow recorded at 1,095 cubic feet per second (about 8,200 gallons per second) in August 1934. Now, daily flows of the Colorado River are largely determined by hydroelectric power generation needs and varies between about 8,000-17,000 cubic feet per second (about 60,000-127,000 gallons per second) depending on the time of day, month, and season. Therefore, before Glen Canyon Dam, the Colorado River experienced much higher flood flows and much lower base flows than it does today, and these changes have influenced sand dynamics in Grand Canyon.
In addition to transporting and depositing large amounts of sand, Colorado River floods prior to Glen Canyon Dam would strip vegetation off sandbars. During low flow periods, much of the sand deposited on sandbars and on the channel bottom became exposed. Wind would transport sand from those areas to sand dune fields. Many sand dune fields in Grand Canyon contain or are near important archaeological and cultural sites. Sand can provide protective cover to these sites which are otherwise prone to natural gully erosion processes caused by runoff during intense rainstorms that are common during the annual late-summer monsoon season in Grand Canyon.
The regulated flows of the modern-day Colorado River in Grand Canyon, combined with the greatly diminished sand supply, are not favorable for building or maintaining sandbars. Therefore, without high-flow events sandbars are slowly decreasing in size due to erosion. In addition, regulated flows of the modern river have caused dense stands of vegetation to encroach onto bare sand surfaces, decreasing the amount of area available for campsites in Grand Canyon. Approximately 25,000 recreationists per year travel through Grand Canyon on the Colorado River or hike to the river, and sandbar campsites are an important part of that experience. Additionally, the expansion of riparian vegetation onto otherwise bare sand limits the amount of sand that can be blown from sandbars onto sand dune fields and fill erosional gullies. This has allowed some erosional processes to negatively affect archaeological sites and many of these sites are in danger of being damaged or lost.
High-Flow Experiments
High-flow experiments are conducted when enough sediment from tributaries has been deposited on the bed of the Colorado River such that sand can be mobilized to increase the size of sandbars along the margin of the river in Grand Canyon without transporting out more sand than was present prior to the tributary inputs. This occurs by allowing much larger volumes of water through Glen Canyon Dam for a few days, which transports sand from the river channel to sandbars and beaches. High-flow experiments result in water flows much higher than the typical base-operations flows from Glen Canyon Dam, with between 31,500-45,000 cubic feet per second (about 236,000-337,000 gallons per second) released during the experiments. Although these flows are approximately half the magnitude and a fraction of the duration of the average spring snowmelt floods that occurred prior to Glen Canyon Dam, high-flow experiments can increase the size of sandbars in Grand Canyon. However, because the river’s modern-day flows erode sandbars over time, it is necessary to repeat high-flow experiments to maintain sandbars that erode during base operations. Monitoring results also suggest that there are cumulative effects of sand resupply to dune fields when annual high-flow experiments are conducted consistently in consecutive years. High-flow experiments have been conducted in 1996, 2004, 2008, 2012, 2013, 2014, 2016, and 2018 (November 5-8). Grand Canyon Monitoring and Research Center scientists continue to monitor the effects of these high-flow experiments and provide that information to resource managers and decision makers so they can make informed decisions about managing the resources of Grand Canyon.
Images of the same sandbar before (left panel) and after (right panel) a high flow experiment. Middle pannel shows water entering the Colorado River from Glen Canyon Dam's jet tubes during a high-flow experiment. (Photo credit: USGS) - Science
Below are other science projects associated with this project.
River Sediment Dynamics
Sediment controls the physical habitat of river ecosystems. Changes in the amount and areal distribution of different sediment types cause changes in river-channel form and river habitat. The amount and type of sediment suspended in the water column determines water clarity. Understanding sediment transport and the conditions under which sediment is deposited or eroded from the various...River Geomorphology and Geomorphic Change
River channels and their adjacent floodplains are ever evolving in form and composition in response to changing patterns of streamflow, the quantity and size of supplied sediment, and feedbacks with the riparian and aquatic ecosystems. Changes in channel form affect aquatic and riparian habitats, which are important for plants, animals, and insects. Erosion and deposition of river channels and...Sediment Storage in Grand Canyon
The sandbars exposed along the shoreline of the Colorado River represent only a small fraction of the sand deposits in Grand Canyon, most of which are on the bed of the river in eddies and the channel. Current management practice includes efforts to maintain and build sandbars by releasing high flows from Glen Canyon Dam that are timed to coincide with periods of fine-sediment supply from...River Campsites in Grand Canyon National Park
Sandbars have been used as campsites by river runners and hikers since the first expeditions to the region more than 100 years ago. Sandbar campsites continue to be an important part of the recreational experience for the more than 25,000 hikers and river runners that visit the Colorado River corridor each year. Because the Colorado River is dominated by bedrock cliffs and steep talus slopes...Terrestrial Riparian Vegetation Monitoring: How One Square Meter Can Tell the Story of 245 River Miles
The goal of Grand Canyon Monitoring and Research Center’s (part of the Southwest Biological Science Center) riparian vegetation monitoring program is to assess changes and trends in plant species composition and cover and relate those changes to Glen Canyon Dam operations, river hydrology, climate, and geomorphology. Monitoring is done by annual field-data collection on plant cover and diversity...Overview of Riparian Vegetation in Grand Canyon
Riparian areas are conspicuous belts of dense, green vegetation along streams and rivers, and can be considered “ribbons of life”. Despite covering less than 2 percent of the land area in the southwestern U.S., riparian areas tend to have high species diversity and population density, making them valuable to managers, scientists, and the public. These unique ecosystems act as a link between dry...Connectivity of Sand Resources Along the Colorado River in Grand Canyon
We study the links among different geomorphic processes that affect river valley landscapes in the Colorado River downstream from Glen Canyon Dam, Arizona. Dam-released flows affect the deposition and retention of sandbars that serve as sources for other sand resources, such as windblown sand dunes, throughout the Colorado River ecosystem. The degree to which the landscapes are differentially...Grand Canyon Sandbar Monitoring
Since the completion of Glen Canyon Dam in 1963, the amount of sand supplied to Grand Canyon National Park has been reduced by more than 90 percent. The Paria River, a tributary to the Colorado River 15 miles downstream from the dam, is now the single most important supplier of sand to the Colorado River within the Park. This large reduction in sand supply has resulted in substantial decrease in... - Publications
Below are publications associated with this project.
Filter Total Items: 30Quantifying geomorphic and vegetation change at sandbar campsites in response to flow regulation and controlled floods, Grand Canyon National Park, Arizona
Sandbars along the Colorado River in Grand Canyon National Park, USA, are an important recreational resource used as campsites by over 25,000 river runners and hikers annually. The number and size of campsites decreased following the completion of Glen Canyon Dam in 1963 due to reductions of sediment that replenish sandbars and increases in vegetation cover caused by flow regulation. Campsite areaAuthorsDaniel R. Hadley, Paul E. Grams, Matthew A. KaplinskiGeomorphology and vegetation change at Colorado River campsites, Marble and Grand Canyons, Arizona
Sandbars along the Colorado River are used as campsites by river runners and hikers and are an important recreational resource within Grand Canyon National Park, Arizona. Regulation of the flow of river water through Glen Canyon Dam has reduced the amount of sediment available to be deposited as sandbars, has reduced the magnitude and frequency of flooding events, and has increased the magnitude oAuthorsDaniel R. Hadley, Paul E. Grams, Matthew A. Kaplinski, Joseph E. Hazel, Roderic A. ParnellAutomated remote cameras for monitoring alluvial sandbars on the Colorado River in Grand Canyon, Arizona
Automated camera systems deployed at 43 remote locations along the Colorado River corridor in Grand Canyon National Park, Arizona, are used to document sandbar erosion and deposition that are associated with the operations of Glen Canyon Dam. The camera systems, which can operate independently for a year or more, consist of a digital camera triggered by a separate data controller, both of which arAuthorsPaul E. Grams, Robert B. Tusso, Daniel BuscombeVariability in eddy sandbar dynamics during two decades of controlled flooding of the Colorado River in the Grand Canyon
Sandbars are iconic features of the Colorado River in the Grand Canyon, Arizona, U.S.A. Following completion of Glen Canyon Dam in 1963, sediment deficit conditions caused erosion of eddy sandbars throughout much of the 360 km study reach downstream from the dam. Controlled floods in 1996, 2004, and 2008 demonstrated that sand on the channel bed could be redistributed to higher elevations, and thaAuthorsErich R. Mueller, Paul E. Grams, Joseph E. Hazel, John C. SchmidtRiparian vegetation, Colorado River, and climate: five decades of spatiotemporal dynamics in the Grand Canyon with river regulation
Documentation of the interacting effects of river regulation and climate on riparian vegetation has typically been limited to small segments of rivers or focused on individual plant species. We examine spatiotemporal variability in riparian vegetation for the Colorado River in Grand Canyon relative to river regulation and climate, over the five decades since completion of the upstream Glen CanyonAuthorsJoel B. Sankey, Barbara E. Ralston, Paul E. Grams, John C. Schmidt, Laura E. CagneyBuilding sandbars in the Grand Canyon
In 1963, the U.S. Department of the Interior’s Bureau of Reclamation finished building Glen Canyon Dam on the Colorado River in northern Arizona, 25 kilometers upstream from Grand Canyon National Park. The dam impounded 300 kilometers of the Colorado River, creating Lake Powell, the nation’s second largest reservoir. By 1974, scientists found that the downstream river’s alluvial sandbars were erodAuthorsPaul E. Grams, John C. Schmidt, Scott A. Wright, David Topping, Theodore S. Melis, David M. RubinDo management actions to restore rare habitat benefit native fish conservation? Distribution of juvenile native fish among shoreline habitats of the Colorado River
Many management actions in aquatic ecosystems are directed at restoring or improving specific habitats to benefit fish populations. In the Grand Canyon reach of the Colorado River, experimental flow operations as part of the Glen Canyon Dam Adaptive Management Program have been designed to restore sandbars and associated backwater habitats. Backwaters can have warmer water temperatures than otherAuthorsMichael J. Dodrill, Charles B. Yackulic, Brandon Gerig, William E. Pine, Josh Korman, Colton FinchThe influence of controlled floods on fine sediment storage in debris fan-affected canyons of the Colorado River basin
Prior to the construction of large dams on the Green and Colorado Rivers, annual floods aggraded sandbars in lateral flow-recirculation eddies with fine sediment scoured from the bed and delivered from upstream. Flows greater than normal dam operations may be used to mimic this process in an attempt to increase time-averaged sandbar size. These controlled floods may rebuild sandbars, but sedimentAuthorsErich R. Mueller, Paul E. Grams, John C. Schmidt, Joseph E. Hazel, Jason S. Alexander, Matt KaplinskiFood-web dynamics in a large river discontinuum
Nearly all ecosystems have been altered by human activities, and most communities are now composed of interacting species that have not co-evolved. These changes may modify species interactions, energy and material flows, and food-web stability. Although structural changes to ecosystems have been widely reported, few studies have linked such changes to dynamic food-web attributes and patterns of eAuthorsWyatt F. Cross, Colden V. Baxter, Emma J. Rosi-Marshall, Robert O. Hall, Theodore A. Kennedy, Kevin C. Donner, Holly A. Wellard Kelly, Sarah E.Z. Seegert, Kathrine E. Behn, Michael D. YardEstimating recruitment dynamics and movement of rainbow trout (Oncorhynchus mykiss) in the Colorado River in Grand Canyon using an integrated assessment model
We used an integrated assessment model to examine effects of flow from Glen Canyon Dam, Arizona, USA, on recruitment of nonnative rainbow trout (Oncorhynchus mykiss) in the Colorado River and to estimate downstream migration from Glen Canyon to Marble Canyon, a reach used by endangered native fish. Over a 20-year period, recruitment of rainbow trout in Glen Canyon increased with the annual flow voAuthorsJosh Korman, Steven J.D. Martell, Carl J. Walters, Andrew S. Makinster, Lewis G. Coggins, Michael D. Yard, William R. PersonsEcosystem ecology meets adaptive management: food web response to a controlled flood on the Colorado River, Glen Canyon
Large dams have been constructed on rivers to meet human demands for water, electricity, navigation, and recreation. As a consequence, flow and temperature regimes have been altered, strongly affecting river food webs and ecosystem processes. Experimental high‐flow dam releases, i.e., controlled floods, have been implemented on the Colorado River, USA, in an effort to reestablish pulsed flood evenAuthorsWyatt F. Cross, Colden V. Baxter, Kevin C. Donner, Emma J. Rosi-Marshall, Theodore A. Kennedy, Robert O. Hall, Holly A. Wellard Kelly, R. Scott RogersEffects of fluctuating flows and a controlled flood on incubation success and early survival rates and growth of age-0 rainbow trout in a large regulated river
Hourly fluctuations in flow from Glen Canyon Dam were increased in an attempt to limit the population of nonnative rainbow trout Oncorhynchus mykiss in the Colorado River, Arizona, due to concerns about negative effects of nonnative trout on endangered native fishes. Controlled floods have also been conducted to enhance native fish habitat. We estimated that rainbow trout incubation mortality rateAuthorsJosh Korman, Matthew Kaplinski, Theodore S. Melis - Web Tools
Below are data or web applications associated with this project.
Predicted Shorelines for High Flows on the Colorado River Application
This application highlights modeled flows of the Colorado River for a discharge of 41,000 cubic feet per second (cfs) that is approximate to recent (2012 - 2018) and future anticipated water releases associated with a High Flow Experiments conducted from Glen Canyon Dam near Page, Arizona. These data are to help visualize the water levels during High Flow Events in relation to othe
APPLICATION - Discharge, Sediment, and Water Quality Monitoring Application
This link launches the Grand Canyon Monitoring and Research Center’s discharge, sediment and water quality monitoring application gateway. Sediment and water quality information can be accessed from here for our on-going monitoring taking place across the Southwest U.S.
APPLICATION - Grand Canyon Sandbar Monitoring
Several applications related to the Grand Canyon Monitoring and Research Center’s long-term sandbar monitoring project can be accessed here, including the sandbar area and volume tool and applications highlighting changes to sandbars as a result of High-Flow Events (HFEs) conducted by Glen Canyon Dam near Page, Arizona.
- Partners
Below are partners associated with this project.