Peter Griffiths
Peter Griffiths serves as the Regional Director and the Deputy Regional Director for Operations for the USGS Rocky Mountain Region.
Professional Experience
U.S. Geological Survey, Denver, CO, 2015 to present. Deputy Regional Director for Operations, Rocky Mountain Region.
U.S. Geological Survey, Denver, CO, 2009 to 2015. Assistant Chief, Central Branch of the National Research Program, Water Mission Area.
U.S. Geological Survey, Tucson, AZ, 2005 to 2009. Research Hydrologist, National Research Program.
Education and Certifications
M.S., 1995, University of Arizona, Geosciences (Minor in Hydrology)
B.A., 1987, Yale University, Archeological Studies
Science and Products
Filter Total Items: 34
Sediment yield and runoff frequency of small drainage basins in the Mojave Desert, California and Nevada
No abstract available.
Authors
Peter G. Griffiths, R. Hereford, R. H. Webb
Sediment yield and runoff frequency of small drainage basins in the Mojave Desert, U.S.A
Sediment yield from small arid basins, particularly in the Mojave Desert, is largely unknown owing to the ephemeral nature of these fluvial systems and long recurrence interval of flow events. We examined 27 reservoirs in the northern and eastern Mojave Desert that trapped sediment from small (< 1 km2) drainage basins on alluvial fans over the past 100 yr, calculated annual sediment yield, and est
Authors
Peter G. Griffiths, R. Hereford, R. H. Webb
Debris flow deposition and reworking by the Colorado River in Grand Canyon, Arizona
Flow regulation by large dams affects downstream flow competence and channel maintenance. Debris flows from 740 tributaries in Grand Canyon, Arizona, transport coarse‐grained sediment onto debris fans adjacent to the Colorado River. These debris fans constrict the river to form rapids and are reworked during river flows that entrain particles and transport them downstream. Beginning in 1963, flood
Authors
Brian J. Yanites, Robert H. Webb, Peter G. Griffiths, Christopher S. Magirl
The state of the Colorado River ecosystem in Grand Canyon: A report of the Grand Canyon Monitoring and Research Center 1991-2004
This report is an important milestone in the effort by the Secretary of the Interior to implement the Grand Canyon Protection Act of 1992 (GCPA; title XVIII, secs. 1801-1809, of Public Law 102-575), the most recent authorizing legislation for Federal efforts to protect resources downstream from Glen Canyon Dam. The chapters that follow are intended to provide decision makers and the American publi
Changes in the water surface profile of the Colorado River in Grand Canyon, Arizona, between 1923 and 2000
In 1923, a U.S. Geological Survey expedition surveyed the water surface profile of the Colorado River through Grand Canyon with theodolite and stadia rod. In 2000, lidar overflights collected topographic data centered on the river corridor, allowing construction of a new water surface profile and detection of change in the profile since 1923. By registering the surveys with respect to each other o
Authors
Christopher S. Magirl, Robert H. Webb, Peter G. Griffiths
Frequency and initiation of debris flows in Grand Canyon, Arizona
Debris flows from 740 tributaries transport sediment into the Colorado River in Grand Canyon, Arizona, creating rapids that control its longitudinal profile. Debris flows mostly occur when runoff triggers failures in colluvium by a process termed “the fire hose effect.” Debris flows originate from a limited number of geologic strata, almost exclusively shales or other clay‐rich, fine‐grained forma
Authors
Peter G. Griffiths, Robert Webb, Theodore S. Melis
Frequency of debris flows in Grand Canyon
No abstract available.
Authors
Robert H. Webb, Peter G. Griffiths, Tillie A. Klearman
Debris flows and the Colorado River
No abstract available.
Authors
Robert Webb, Theodore S. Melis, Peter G. Griffiths
Long-term sand supply to Coachella Valley Fringe-toed Lizard Habitat in the Northern Coachella Valley, California
The Coachella Valley fringe-toed lizard (Uma inornata) is a federally listed threatened species that inhabits active sand dunes in the vicinity of Palm Springs, California. The Whitewater Floodplain and Willow Hole Reserves provide some of the primary remaining habitat for this species. The sediment-delivery system that creates these active sand dunes consists of fluvial depositional areas fed epi
Authors
Peter G. Griffiths, Robert H. Webb, Nicholas Lancaster, Charles A. Kaehler, Scott C. Lundstrom
Techniques for estimating sediment yield of ungaged tributaries on the southern Colorado Plateau
Numerous regional sediment transport data are used to evaluate three techniques for estimating streamflow sediment yield from ungaged tributaries of the Colorado River in Grand Canyon. These techniques include: (1) a regression equation relating drainage area to sediment yield for all relevant sediment-yield data from northern Arizona, (2) an empirical relation developed by Renard (1972) selected
Authors
Robert Webb, Peter G. Griffiths, Daniel R. Hartley
Sediment delivery by ungaged tributaries of the Colorado River in Grand Canyon
No abstract available.
Authors
Robert H. Webb, Peter G. Griffiths
Monitoring of coarse sediment inputs to the Colorado River In Grand Canyon
No abstract available.
Authors
Robert H. Webb, Peter G. Griffiths
Science and Products
Filter Total Items: 34
Sediment yield and runoff frequency of small drainage basins in the Mojave Desert, California and Nevada
No abstract available.
Authors
Peter G. Griffiths, R. Hereford, R. H. Webb
Sediment yield and runoff frequency of small drainage basins in the Mojave Desert, U.S.A
Sediment yield from small arid basins, particularly in the Mojave Desert, is largely unknown owing to the ephemeral nature of these fluvial systems and long recurrence interval of flow events. We examined 27 reservoirs in the northern and eastern Mojave Desert that trapped sediment from small (< 1 km2) drainage basins on alluvial fans over the past 100 yr, calculated annual sediment yield, and est
Authors
Peter G. Griffiths, R. Hereford, R. H. Webb
Debris flow deposition and reworking by the Colorado River in Grand Canyon, Arizona
Flow regulation by large dams affects downstream flow competence and channel maintenance. Debris flows from 740 tributaries in Grand Canyon, Arizona, transport coarse‐grained sediment onto debris fans adjacent to the Colorado River. These debris fans constrict the river to form rapids and are reworked during river flows that entrain particles and transport them downstream. Beginning in 1963, flood
Authors
Brian J. Yanites, Robert H. Webb, Peter G. Griffiths, Christopher S. Magirl
The state of the Colorado River ecosystem in Grand Canyon: A report of the Grand Canyon Monitoring and Research Center 1991-2004
This report is an important milestone in the effort by the Secretary of the Interior to implement the Grand Canyon Protection Act of 1992 (GCPA; title XVIII, secs. 1801-1809, of Public Law 102-575), the most recent authorizing legislation for Federal efforts to protect resources downstream from Glen Canyon Dam. The chapters that follow are intended to provide decision makers and the American publi
Changes in the water surface profile of the Colorado River in Grand Canyon, Arizona, between 1923 and 2000
In 1923, a U.S. Geological Survey expedition surveyed the water surface profile of the Colorado River through Grand Canyon with theodolite and stadia rod. In 2000, lidar overflights collected topographic data centered on the river corridor, allowing construction of a new water surface profile and detection of change in the profile since 1923. By registering the surveys with respect to each other o
Authors
Christopher S. Magirl, Robert H. Webb, Peter G. Griffiths
Frequency and initiation of debris flows in Grand Canyon, Arizona
Debris flows from 740 tributaries transport sediment into the Colorado River in Grand Canyon, Arizona, creating rapids that control its longitudinal profile. Debris flows mostly occur when runoff triggers failures in colluvium by a process termed “the fire hose effect.” Debris flows originate from a limited number of geologic strata, almost exclusively shales or other clay‐rich, fine‐grained forma
Authors
Peter G. Griffiths, Robert Webb, Theodore S. Melis
Frequency of debris flows in Grand Canyon
No abstract available.
Authors
Robert H. Webb, Peter G. Griffiths, Tillie A. Klearman
Debris flows and the Colorado River
No abstract available.
Authors
Robert Webb, Theodore S. Melis, Peter G. Griffiths
Long-term sand supply to Coachella Valley Fringe-toed Lizard Habitat in the Northern Coachella Valley, California
The Coachella Valley fringe-toed lizard (Uma inornata) is a federally listed threatened species that inhabits active sand dunes in the vicinity of Palm Springs, California. The Whitewater Floodplain and Willow Hole Reserves provide some of the primary remaining habitat for this species. The sediment-delivery system that creates these active sand dunes consists of fluvial depositional areas fed epi
Authors
Peter G. Griffiths, Robert H. Webb, Nicholas Lancaster, Charles A. Kaehler, Scott C. Lundstrom
Techniques for estimating sediment yield of ungaged tributaries on the southern Colorado Plateau
Numerous regional sediment transport data are used to evaluate three techniques for estimating streamflow sediment yield from ungaged tributaries of the Colorado River in Grand Canyon. These techniques include: (1) a regression equation relating drainage area to sediment yield for all relevant sediment-yield data from northern Arizona, (2) an empirical relation developed by Renard (1972) selected
Authors
Robert Webb, Peter G. Griffiths, Daniel R. Hartley
Sediment delivery by ungaged tributaries of the Colorado River in Grand Canyon
No abstract available.
Authors
Robert H. Webb, Peter G. Griffiths
Monitoring of coarse sediment inputs to the Colorado River In Grand Canyon
No abstract available.
Authors
Robert H. Webb, Peter G. Griffiths