Southwest Biological Science Center

Glen Canyon Dam Adaptive Management Program (GCDAMP)

The Grand Canyon Monitoring and Research Center (GCMRC) is the science provider for the Glen Canyon Dam Adaptive Management Program (GCDAMP), and its scientists study the effects of Glen Canyon Dam operations on the resources of Grand Canyon. More information about the GCDAMP can be found at the Bureau of Reclamation and the GCDAMP Wiki page. Neither of these sites are US Geological Survey (USGS) websites, so accessing those sites means you will leave the USGS website and will be entering other domains. 

Bureau of Reclamation, GCDAMP Page

Bureau of Reclamation, GCDAMP Page

The Bureau of Reclamation's web page for the Glen Canyon Dam Adaptive Management Program contains a wealth of information on Glen Canyon Dam and the Adaptive Management Program (GCDAMP).  This will take you to a site not maintained by the USGS.

BOR GCDAMP

GCDAMP Wiki Pages

GCDAMP Wiki Pages

An unofficial, yet valuable resource for all things related to the adaptive management program, including how the adaptive management process works, recent meetings, and more.  This site is not maintained by USGS or any other government entity.

GCDAMP Wiki
Filter Total Items: 25
Date published: December 30, 2016
Status: Active

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...

Date published: December 23, 2016
Status: Active

Population Dynamics of Endangered Humpback Chub in Grand Canyon

Construction of Glen Canyon Dam has led to large changes in environmental conditions of the downriver Colorado River. Whereas the pre-dam Colorado River experienced large seasonal variation in temperature and discharge and was highly turbid, the post-dam Colorado River is far less variable in terms of temperature and discharge and is frequently clear. Many nonnative fish species had already...

Date published: December 23, 2016
Status: Active

Understanding Factors Influencing Rainbow Trout Growth in the Colorado River

Rainbow trout is a desirable sport fish that has been introduced in many locations around the world. Although introductions of rainbow trout and other nonnative fishes provide recreational fishing opportunities, they also pose threats to native fish populations. The Glen Canyon Dam Adaptive Management Program has tasked scientists and managers with identifying management options that allow...

Date published: December 22, 2016
Status: Active

SBSC Scientist Directory

Click on "Science" to go to the SBSC scientist directory. When you click on a scientist's name (you may need to scroll down to see all the names), you will be taken to that scientist's professional page and contact information. 

Date published: December 22, 2016
Status: Active

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...

Date published: December 21, 2016
Status: Active

Effects of Water Clarity on Survival of Endangered Humpback Chub

Introduced rainbow trout and brown trout are considered a threat to the endangered humpback chub in the Colorado River in Grand Canyon. These introduced species eat native fish, but impacts are difficult to assess because predation vulnerability depends on the physical conditions under which predation takes place. We studied how predation vulnerability of juvenile humpback chub changes in...

Contacts: David Ward
Date published: December 20, 2016
Status: Active

Riparian Remote Sensing in the Colorado River and Grand Canyon Region

Riparian vegetation has increased dramatically along the Colorado River downstream of Glen Canyon Dam since the closure of the dam in 1963. The spatial patterns and temporal rates of vegetation increase occur due to changes in river hydrology, dam operations, and climate. The increase in vegetation, particularly onto otherwise bare sandbars, has impacted recreational, geomorphological,...

Date published: December 15, 2016
Status: Active

Economics of Outdoor Recreation

Economic research at Grand Canyon Monitoring and Research Center is used to determine economic benefits of outdoor recreation in Glen Canyon National Recreation Area below Glen Canyon Dam and in Grand Canyon National Park, as affected by operation of Glen Canyon Dam. This research identifies recreationists’ preferences for attributes associated with their trips, spending that occurs regionally...

Contacts: Lucas Bair
Date published: December 9, 2016
Status: Active

Insect Drift

All aquatic invertebrates drift downstream at some point in their life cycle. Invertebrates may drift to find more preferable habitats, to leave the water during their transition from aquatic larvae to terrestrial adults, or accidentally such as when swept off the river bed by a flood. Regardless, when they enter the drift, invertebrates become particularly susceptible to predation by several...

Date published: December 8, 2016
Status: Active

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...

Date published: December 8, 2016
Status: Active

Adaptive Management

In 1996, the Secretary of the Interior signed a formal decision altering the historical flows from Glen Canyon Dam and establishing the Glen Canyon Dam Adaptive Management Program (GCDAMP). In the context of the management of Glen Canyon Dam, adaptive management was selected to create a process whereby “the effects of dam operations on downstream resources would be assessed and the results of...

Date published: December 5, 2016
Status: Active

Sediment Storage in the Colorado River

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...