Skip to main content
U.S. flag

An official website of the United States government

Chris Holmquist-Johnson, PhD

Chris Holmquist-Johnson is a Hydrologist at the Fort Collins Science Center. 

Science and Products

link
The Yampa River at Dinosaur National Monument.

Water Management Studies

As the need for incorporating biological objectives into water management decisions has grown, so has the need for methods and metrics to incorporate predictions of relevant biological responses into an increasingly complex decision environment that attempts to balance multiple uses.
By
Fort Collins Science Center
link

Water Management Studies

As the need for incorporating biological objectives into water management decisions has grown, so has the need for methods and metrics to incorporate predictions of relevant biological responses into an increasingly complex decision environment that attempts to balance multiple uses.
Learn More
link
Scientist Leanne Hanson releasing an unmanned aircraft for a study. USGS photo.

Small Unoccupied Aircraft System (sUAS) Flights

Small Unmanned Aircraft Systems (sUAS) are an emerging technology which may result in safer and improved methods to conduct wildlife surveys. The objective of this task is to test the capabilities of various cameras and sensors onboard a small Unoccupied (or unmanned) Aircraft System (sUAS) to determine if they are a useful and effective tool to inventory various flora and fauna important to USGS...
By
Fort Collins Science Center
link

Small Unoccupied Aircraft System (sUAS) Flights

Small Unmanned Aircraft Systems (sUAS) are an emerging technology which may result in safer and improved methods to conduct wildlife surveys. The objective of this task is to test the capabilities of various cameras and sensors onboard a small Unoccupied (or unmanned) Aircraft System (sUAS) to determine if they are a useful and effective tool to inventory various flora and fauna important to USGS...
Learn More

Orthoimagery, digital elevation, digital terrain, final surface, and vegetation classification models for four stream catchments in western Colorado 2016

Unmanned Aerial System (UAS) flights were conducted over four stream catchments in Rio Blanco County, Colorado, during the summer of 2016. Two sties had active oil and gas operations within the basin whereas the other two sites did not. Structure from motion (SfM) was used to align raw images and create a dense point cloud, georectified orthoimage, and Digital Elevation Model (DEM) for each basin.
By
Colorado Water Science Center

Photogrammetric data collected by small unoccupied aircraft system for vegetation analysis at three study reaches along the Verde River, Arizona, December 2017

The U.S. Geological Survey collected low-altitude airborne visual imagery via a multirotor, small unoccupied aircraft system (sUAS) along with Real Time Kinematic (RTK) GPS survey data at three study sites (Beasley Flat, Childs, and Sheep Bridge) along the Verde River in Arizona in December 2017. Visual imagery was collected in jpg format and Structure from Motion techniques were applied to the vi
By
Fort Collins Science Center

Orthoimagery and elevation data derived from UAS imagery for Palmyra Atoll, USA 2016 (ver. 1.1, November 2020)

Point clouds, high resolution digital surface models (DSM), and high resolution orthoimagery of Palmyra Atoll, USA, were generated from aerial 3-color and 5-band imagery collected October 2016 using Unoccupied Aerial Systems (UAS, or "drones"). Data were processed in sections corresponsing to flight areas using photogrammetry to generate three-dimensional point clouds (.las) by identifying pixels
By
Columbia Environmental Research Center

Thermal infrared, multispectral, and photogrammetric data collected by drone for hydrogeologic analysis of the East River and Coal Creek beaver-impacted corridors near Crested Butte, Colorado

The U.S. Geological Survey collected low-altitude (typically 200-350 ft als) airborne thermal infrared, multispectral, and visual imagery data via a multirotor, small unoccupied aircraft system deployed along beaver-impacted sections of the East River and Coal Creek stream corridors, near the town of Crested Butte, CO. Visual imagery was collected in jpg format, and the images were compiled automa
By
Water Resources Mission Area

Thermal infrared and photogrammetric data collected by small unoccupied aircraft system for hydrogeologic analysis of Oh-be-joyful Creek, Gunnison National Forest, Colorado, August 2017

The U.S. Geological Survey collected low-altitude airborne thermal infrared data and visual imagery via a multirotor, small unoccupied aircraft system deployed from the northern bank of Oh-be-joyful Creek and adjacent to the Peeler fault, approximately 6 kilometers northwest of the town of Crested Butte, in Gunnison National Forest, Colorado, on August 17, 2017. Thermal infrared still images were
By
Water Resources Mission Area, Groundwater and Streamflow Information Program
No results found.

Predicting bird guilds using vegetation composition and structure on a wild and scenic river in Arizona

Riparian areas are among the most ecologically diverse terrestrial ecosystems but make up <2% of landscape area in southwestern USA. Many species of resident and neotropical migratory birds utilize riparian habitats for breeding, foraging, and nesting. We quantified vegetation composition and structure to predict bird guilds on Wild and Scenic portions of the Verde River, Arizona. We grouped plant
Authors
Erin S. Cubley, Heather L. Bateman, Sidney B. Riddle, Christopher Holmquist-Johnson, David M. Merritt
By
Ecosystems Mission Area, Fort Collins Science Center

Efficient hydrogeological characterization of remote stream corridors using drones

This project demonstrates the successful use of small unoccupied aircraft system (sUASs) for hydrogeological characterization of a remote stream reach in a rugged mountain terrain. Thermal infrared, visual imagery, and derived digital surface models are used to inform conceptual models of groundwater/surface‐water exchange and efficiently geolocate zones of preferential groundwater discharge that
Authors
Martin A. Briggs, Cian B. Dawson, Christopher Holmquist-Johnson, Kenneth H. Williams, John W. Lane
By
Water Resources Mission Area, Toxic Substances Hydrology

Development of a decision support tool for water and resource management using biotic, abiotic, and hydrological assessments of Topock Marsh, Arizona

Topock Marsh is a large wetland adjacent to the Colorado River and the main feature of Havasu National Wildlife Refuge (Havasu NWR) in southern Arizona. In 2010, the U.S. Fish and Wildlife Service (FWS) and Bureau of Reclamation began a project to improve water management capabilities at Topock Marsh and protect habitats and species. Initial construction required a drawdown, which caused below-ave
Authors
Christopher Holmquist-Johnson, Leanne Hanson, Joan Daniels, Colin Talbert, Jeanette Haegele
By
Ecosystems Mission Area, Fort Collins Science Center

Experimental flights using a small unmanned aircraft system for mapping emergent sandbars

The US Geological Survey and Parallel Inc. conducted experimental flights with the Tarantula Hawk (T-Hawk) unmanned aircraft system (UAS ) at the Dyer and Cottonwood Ranch properties located along reaches of the Platte River near Overton, Nebraska, in July 2013. We equipped the T-Hawk UAS platform with a consumer-grade digital camera to collect imagery of emergent sandbars in the reaches and used
Authors
Paul J. Kinzel, Mark A. Bauer, Mark R. Feller, Christopher Holmquist-Johnson, Todd Preston
By
Geosciences and Environmental Change Science Center, Northern Rocky Mountain Science Center

Evaluation of the Raven sUAS to detect and monitor greater sage-grouse leks within the Middle Park population

Staff from the U.S. Geological Survey Fort Collins Science Center and the Colorado Parks and Wildlife Hot Sulphur Springs Office began discussions in 2011 for a proof of concept study to test the Raven RQ-11A small Unmanned Aircraft System (Raven sUAS) for its suitability to detect and monitor greater sage-grouse (Centrocercus urophasianus) breeding sites (leks). During April 2013, the Raven sUAS
Authors
Leanne Hanson, Christopher L. Holmquist-Johnson, Michelle L. Cowardin
By
Ecosystems Mission Area, Fort Collins Science Center

User's manual for the upper Delaware River riverine environmental flow decision support system (REFDSS), Version 1.1.2

Between 2002 and 2006, the Fort Collins Science Center (FORT) at the U.S. Geological Survey (USGS) conducted field surveys, organized workshops, and performed analysis of habitat for trout and shad in the Upper Delaware River Basin. This work culminated in the development of decision support system software (the Delaware River DSS–DRDSS, Bovee and others, 2007) that works in conjunction with the D
Authors
Colin Talbert, Kelly O. Maloney, Chris Holmquist-Johnson, Leanne Hanson
By
Ecosystems Mission Area, Fort Collins Science Center

Channel Maintenance and Flushing Flows for the Klamath River Below Iron Gate Dam, California

The Klamath River is a major river in northern California and southern Oregon. Iron Gate Dam divides the river into the two subunits where there is a significant change in utilization of the river. Downstream of Iron Gate Dam, the river is very important for the propagation of salmon. To address concerns relating to substrate conditions in the mainstem Klamath River below Iron Gate Dam, the Arcata
Authors
Cristopher L. Holmquist-Johnson, Robert T. Milhous
By
Ecosystems Mission Area, Fort Collins Science Center

Relation between Streamflow of Swiftcurrent Creek, Montana, and the Geometry of Passage for Bull Trout (Salvelinus confluentus)

Operation of Sherburne Dam in northcentral Montana has typically reduced winter streamflow in Swiftcurrent Creek downstream of the dam and resulted in passage limitations for bull trout (Salvelinus confluentus). We defined an empirical relation between discharge in Swiftcurrent Creek between Sherburne Dam and the downstream confluence with Boulder Creek and fish passage geometry by considering how
Authors
Gregor T. Auble, Christopher L. Holmquist-Johnson, Jim T. Mogen, Lynn R. Kaeding, Zachary H. Bowen
By
Ecosystems Mission Area, Fort Collins Science Center

Rock ramp design guidelines

Rock ramps or roughened channels consist of steep reaches stabilized by large immobile material (riprap). Primary objectives for rock ramps include: Create adequate head for diversionMaintain fish passage during low-flow conditionsMaintain hydraulic conveyance during high-flow conditionsSecondary objectives for rock ramp design include:Emulate natural systemsMinimize costsThe rock ramp consists of
Authors
David M. Mooney, Christopher L. Holmquist-Johnson, Susan Broderick
By
Ecosystems Mission Area, Fort Collins Science Center

Qualitative evaluation of rock weir field performance and failure mechanisms

River spanning loose-rock structures provide sufficient head for irrigation diversion, permit fish passage over barriers, protect banks, stabilize degrading channels, activate side channels, reconnect floodplains, and create in-channel habitat. These structures are called by a variety of names including rock weirs, alphabet (U-, A-, V-, W-) weirs, Jhooks, and rock ramps. These structures share the
Authors
David M. Mooney, Christopher L. Holmquist-Johnson, Elaina Holburn
By
Ecosystems Mission Area, Fort Collins Science Center

Non-USGS Publications**

Holmquist-Johnson, C., D. Raff, and K. Russell. 2009. Bureau of Reclamation Automated Modified Einstein Procedure (BORAMEP) Program for Computing Total Sediment Discharge. Sedimentation and River Hydraulics Group. Denver, CO: Bureau of Reclamation, U.S. Department of the Interior. 48 p.
Holmquist-Johnson, C.L. and D. Raff. 2006. Bureau of Reclamation Automated Modified Einstein Procedure (BORAMEP) Program for Computing Total Sediment Load. Federal Interagency Sedimentation Conference in Reno, NV., April 2-6, 2006. Federal Interagency Sedimentation Project . p. 8.
Holmquist-Johnson, C. 2004. Sediment Model for the Middle Rio Grande – Phase 1, San Acacia Diversion Dam to Elephant Butte Reservoir. Sedimentation and River Hydraulics Group. Denver, CO: U.S. Department of the Interior, Bureau of Reclamation. 91 p.
Holmquist-Johnson, C.L. 2002. Computational methods for determining effective discharge in the Yazoo River Basin, Mississippi Fort Collins, CO: Colorado State University. 146 p.
Watson, C.C., D.P. Roseboom, C.L. Holmquist-Johnson, and M.D. Robeson. 2002. Development of design criteria for siting and spacing of grade control structures, Phase I. Preliminary Report. Fort Collins, CO: Engineering Research Center, Colorado State University. 34 p.
Watson, C.C., B.P. Bledsoe, C.L. Holmquist-Johnson, D.M. Mooney, and A.M. Haas. 1999. Demonstration erosion control monitoring sites: 1999 evaluation. Submitted to: Commander, U.S. Army Corps of Engineers, Engineer Research and Development Center, Vicksburg, Mississippi 39180. Fort Collins, CO: Department of Civil Engineering, Colorado State University. 245 p.
Holmquist-Johnson, C.L., C.I. Thornton, C.C. Watson, and S.R. Abt. 1999. Laboratory Testing of A-Jacks Units for Inland Applications - Hydraulic Property Documentation. Report submitted to Armortec Concrete Erosion Control Systems. Fort Collins, CO: Department of Civil Engineering, Colorado State University. various p.

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

Physical Habitat Simulation (PHABSIM) Software for Windows

The purpose of the Physical Habitat Simulation System (PHABSIM) is to simulate a relationship between streamflow and physical habitat for various life stages of a species of fish or a recreational activity. 

By
Fort Collins Science Center
FORT Hydrologist Jonathan Friedman to co-present research on hydrology of the Green River

FORT Hydrologist Jonathan Friedman to co-present research on hydrology of the Green River

On January 30, Jonathan Friedman (FORT) and Dusty Perkins (NPS) will present research by NPS and FORT scientists (including Chris Holmquist-Johnson...

Read Article
FORT scientists host the second annual Big Rivers Data Integration Workshop

FORT scientists host the second annual Big Rivers Data Integration Workshop

From December 5–6 the Fort Collins Science Center hosted the second annual Big Rivers Data Integration Workshop, combining efforts by scientists at...

Read Article

Science and Products

link
The Yampa River at Dinosaur National Monument.

Water Management Studies

As the need for incorporating biological objectives into water management decisions has grown, so has the need for methods and metrics to incorporate predictions of relevant biological responses into an increasingly complex decision environment that attempts to balance multiple uses.
By
Fort Collins Science Center
link

Water Management Studies

As the need for incorporating biological objectives into water management decisions has grown, so has the need for methods and metrics to incorporate predictions of relevant biological responses into an increasingly complex decision environment that attempts to balance multiple uses.
Learn More
link
Scientist Leanne Hanson releasing an unmanned aircraft for a study. USGS photo.

Small Unoccupied Aircraft System (sUAS) Flights

Small Unmanned Aircraft Systems (sUAS) are an emerging technology which may result in safer and improved methods to conduct wildlife surveys. The objective of this task is to test the capabilities of various cameras and sensors onboard a small Unoccupied (or unmanned) Aircraft System (sUAS) to determine if they are a useful and effective tool to inventory various flora and fauna important to USGS...
By
Fort Collins Science Center
link

Small Unoccupied Aircraft System (sUAS) Flights

Small Unmanned Aircraft Systems (sUAS) are an emerging technology which may result in safer and improved methods to conduct wildlife surveys. The objective of this task is to test the capabilities of various cameras and sensors onboard a small Unoccupied (or unmanned) Aircraft System (sUAS) to determine if they are a useful and effective tool to inventory various flora and fauna important to USGS...
Learn More

Orthoimagery, digital elevation, digital terrain, final surface, and vegetation classification models for four stream catchments in western Colorado 2016

Unmanned Aerial System (UAS) flights were conducted over four stream catchments in Rio Blanco County, Colorado, during the summer of 2016. Two sties had active oil and gas operations within the basin whereas the other two sites did not. Structure from motion (SfM) was used to align raw images and create a dense point cloud, georectified orthoimage, and Digital Elevation Model (DEM) for each basin.
By
Colorado Water Science Center

Photogrammetric data collected by small unoccupied aircraft system for vegetation analysis at three study reaches along the Verde River, Arizona, December 2017

The U.S. Geological Survey collected low-altitude airborne visual imagery via a multirotor, small unoccupied aircraft system (sUAS) along with Real Time Kinematic (RTK) GPS survey data at three study sites (Beasley Flat, Childs, and Sheep Bridge) along the Verde River in Arizona in December 2017. Visual imagery was collected in jpg format and Structure from Motion techniques were applied to the vi
By
Fort Collins Science Center

Orthoimagery and elevation data derived from UAS imagery for Palmyra Atoll, USA 2016 (ver. 1.1, November 2020)

Point clouds, high resolution digital surface models (DSM), and high resolution orthoimagery of Palmyra Atoll, USA, were generated from aerial 3-color and 5-band imagery collected October 2016 using Unoccupied Aerial Systems (UAS, or "drones"). Data were processed in sections corresponsing to flight areas using photogrammetry to generate three-dimensional point clouds (.las) by identifying pixels
By
Columbia Environmental Research Center

Thermal infrared, multispectral, and photogrammetric data collected by drone for hydrogeologic analysis of the East River and Coal Creek beaver-impacted corridors near Crested Butte, Colorado

The U.S. Geological Survey collected low-altitude (typically 200-350 ft als) airborne thermal infrared, multispectral, and visual imagery data via a multirotor, small unoccupied aircraft system deployed along beaver-impacted sections of the East River and Coal Creek stream corridors, near the town of Crested Butte, CO. Visual imagery was collected in jpg format, and the images were compiled automa
By
Water Resources Mission Area

Thermal infrared and photogrammetric data collected by small unoccupied aircraft system for hydrogeologic analysis of Oh-be-joyful Creek, Gunnison National Forest, Colorado, August 2017

The U.S. Geological Survey collected low-altitude airborne thermal infrared data and visual imagery via a multirotor, small unoccupied aircraft system deployed from the northern bank of Oh-be-joyful Creek and adjacent to the Peeler fault, approximately 6 kilometers northwest of the town of Crested Butte, in Gunnison National Forest, Colorado, on August 17, 2017. Thermal infrared still images were
By
Water Resources Mission Area, Groundwater and Streamflow Information Program
No results found.

Predicting bird guilds using vegetation composition and structure on a wild and scenic river in Arizona

Riparian areas are among the most ecologically diverse terrestrial ecosystems but make up <2% of landscape area in southwestern USA. Many species of resident and neotropical migratory birds utilize riparian habitats for breeding, foraging, and nesting. We quantified vegetation composition and structure to predict bird guilds on Wild and Scenic portions of the Verde River, Arizona. We grouped plant
Authors
Erin S. Cubley, Heather L. Bateman, Sidney B. Riddle, Christopher Holmquist-Johnson, David M. Merritt
By
Ecosystems Mission Area, Fort Collins Science Center

Efficient hydrogeological characterization of remote stream corridors using drones

This project demonstrates the successful use of small unoccupied aircraft system (sUASs) for hydrogeological characterization of a remote stream reach in a rugged mountain terrain. Thermal infrared, visual imagery, and derived digital surface models are used to inform conceptual models of groundwater/surface‐water exchange and efficiently geolocate zones of preferential groundwater discharge that
Authors
Martin A. Briggs, Cian B. Dawson, Christopher Holmquist-Johnson, Kenneth H. Williams, John W. Lane
By
Water Resources Mission Area, Toxic Substances Hydrology

Development of a decision support tool for water and resource management using biotic, abiotic, and hydrological assessments of Topock Marsh, Arizona

Topock Marsh is a large wetland adjacent to the Colorado River and the main feature of Havasu National Wildlife Refuge (Havasu NWR) in southern Arizona. In 2010, the U.S. Fish and Wildlife Service (FWS) and Bureau of Reclamation began a project to improve water management capabilities at Topock Marsh and protect habitats and species. Initial construction required a drawdown, which caused below-ave
Authors
Christopher Holmquist-Johnson, Leanne Hanson, Joan Daniels, Colin Talbert, Jeanette Haegele
By
Ecosystems Mission Area, Fort Collins Science Center

Experimental flights using a small unmanned aircraft system for mapping emergent sandbars

The US Geological Survey and Parallel Inc. conducted experimental flights with the Tarantula Hawk (T-Hawk) unmanned aircraft system (UAS ) at the Dyer and Cottonwood Ranch properties located along reaches of the Platte River near Overton, Nebraska, in July 2013. We equipped the T-Hawk UAS platform with a consumer-grade digital camera to collect imagery of emergent sandbars in the reaches and used
Authors
Paul J. Kinzel, Mark A. Bauer, Mark R. Feller, Christopher Holmquist-Johnson, Todd Preston
By
Geosciences and Environmental Change Science Center, Northern Rocky Mountain Science Center

Evaluation of the Raven sUAS to detect and monitor greater sage-grouse leks within the Middle Park population

Staff from the U.S. Geological Survey Fort Collins Science Center and the Colorado Parks and Wildlife Hot Sulphur Springs Office began discussions in 2011 for a proof of concept study to test the Raven RQ-11A small Unmanned Aircraft System (Raven sUAS) for its suitability to detect and monitor greater sage-grouse (Centrocercus urophasianus) breeding sites (leks). During April 2013, the Raven sUAS
Authors
Leanne Hanson, Christopher L. Holmquist-Johnson, Michelle L. Cowardin
By
Ecosystems Mission Area, Fort Collins Science Center

User's manual for the upper Delaware River riverine environmental flow decision support system (REFDSS), Version 1.1.2

Between 2002 and 2006, the Fort Collins Science Center (FORT) at the U.S. Geological Survey (USGS) conducted field surveys, organized workshops, and performed analysis of habitat for trout and shad in the Upper Delaware River Basin. This work culminated in the development of decision support system software (the Delaware River DSS–DRDSS, Bovee and others, 2007) that works in conjunction with the D
Authors
Colin Talbert, Kelly O. Maloney, Chris Holmquist-Johnson, Leanne Hanson
By
Ecosystems Mission Area, Fort Collins Science Center

Channel Maintenance and Flushing Flows for the Klamath River Below Iron Gate Dam, California

The Klamath River is a major river in northern California and southern Oregon. Iron Gate Dam divides the river into the two subunits where there is a significant change in utilization of the river. Downstream of Iron Gate Dam, the river is very important for the propagation of salmon. To address concerns relating to substrate conditions in the mainstem Klamath River below Iron Gate Dam, the Arcata
Authors
Cristopher L. Holmquist-Johnson, Robert T. Milhous
By
Ecosystems Mission Area, Fort Collins Science Center

Relation between Streamflow of Swiftcurrent Creek, Montana, and the Geometry of Passage for Bull Trout (Salvelinus confluentus)

Operation of Sherburne Dam in northcentral Montana has typically reduced winter streamflow in Swiftcurrent Creek downstream of the dam and resulted in passage limitations for bull trout (Salvelinus confluentus). We defined an empirical relation between discharge in Swiftcurrent Creek between Sherburne Dam and the downstream confluence with Boulder Creek and fish passage geometry by considering how
Authors
Gregor T. Auble, Christopher L. Holmquist-Johnson, Jim T. Mogen, Lynn R. Kaeding, Zachary H. Bowen
By
Ecosystems Mission Area, Fort Collins Science Center

Rock ramp design guidelines

Rock ramps or roughened channels consist of steep reaches stabilized by large immobile material (riprap). Primary objectives for rock ramps include: Create adequate head for diversionMaintain fish passage during low-flow conditionsMaintain hydraulic conveyance during high-flow conditionsSecondary objectives for rock ramp design include:Emulate natural systemsMinimize costsThe rock ramp consists of
Authors
David M. Mooney, Christopher L. Holmquist-Johnson, Susan Broderick
By
Ecosystems Mission Area, Fort Collins Science Center

Qualitative evaluation of rock weir field performance and failure mechanisms

River spanning loose-rock structures provide sufficient head for irrigation diversion, permit fish passage over barriers, protect banks, stabilize degrading channels, activate side channels, reconnect floodplains, and create in-channel habitat. These structures are called by a variety of names including rock weirs, alphabet (U-, A-, V-, W-) weirs, Jhooks, and rock ramps. These structures share the
Authors
David M. Mooney, Christopher L. Holmquist-Johnson, Elaina Holburn
By
Ecosystems Mission Area, Fort Collins Science Center

Non-USGS Publications**

Holmquist-Johnson, C., D. Raff, and K. Russell. 2009. Bureau of Reclamation Automated Modified Einstein Procedure (BORAMEP) Program for Computing Total Sediment Discharge. Sedimentation and River Hydraulics Group. Denver, CO: Bureau of Reclamation, U.S. Department of the Interior. 48 p.
Holmquist-Johnson, C.L. and D. Raff. 2006. Bureau of Reclamation Automated Modified Einstein Procedure (BORAMEP) Program for Computing Total Sediment Load. Federal Interagency Sedimentation Conference in Reno, NV., April 2-6, 2006. Federal Interagency Sedimentation Project . p. 8.
Holmquist-Johnson, C. 2004. Sediment Model for the Middle Rio Grande – Phase 1, San Acacia Diversion Dam to Elephant Butte Reservoir. Sedimentation and River Hydraulics Group. Denver, CO: U.S. Department of the Interior, Bureau of Reclamation. 91 p.
Holmquist-Johnson, C.L. 2002. Computational methods for determining effective discharge in the Yazoo River Basin, Mississippi Fort Collins, CO: Colorado State University. 146 p.
Watson, C.C., D.P. Roseboom, C.L. Holmquist-Johnson, and M.D. Robeson. 2002. Development of design criteria for siting and spacing of grade control structures, Phase I. Preliminary Report. Fort Collins, CO: Engineering Research Center, Colorado State University. 34 p.
Watson, C.C., B.P. Bledsoe, C.L. Holmquist-Johnson, D.M. Mooney, and A.M. Haas. 1999. Demonstration erosion control monitoring sites: 1999 evaluation. Submitted to: Commander, U.S. Army Corps of Engineers, Engineer Research and Development Center, Vicksburg, Mississippi 39180. Fort Collins, CO: Department of Civil Engineering, Colorado State University. 245 p.
Holmquist-Johnson, C.L., C.I. Thornton, C.C. Watson, and S.R. Abt. 1999. Laboratory Testing of A-Jacks Units for Inland Applications - Hydraulic Property Documentation. Report submitted to Armortec Concrete Erosion Control Systems. Fort Collins, CO: Department of Civil Engineering, Colorado State University. various p.

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

Physical Habitat Simulation (PHABSIM) Software for Windows

The purpose of the Physical Habitat Simulation System (PHABSIM) is to simulate a relationship between streamflow and physical habitat for various life stages of a species of fish or a recreational activity. 

By
Fort Collins Science Center
FORT Hydrologist Jonathan Friedman to co-present research on hydrology of the Green River

FORT Hydrologist Jonathan Friedman to co-present research on hydrology of the Green River

On January 30, Jonathan Friedman (FORT) and Dusty Perkins (NPS) will present research by NPS and FORT scientists (including Chris Holmquist-Johnson...

Read Article
FORT scientists host the second annual Big Rivers Data Integration Workshop

FORT scientists host the second annual Big Rivers Data Integration Workshop

From December 5–6 the Fort Collins Science Center hosted the second annual Big Rivers Data Integration Workshop, combining efforts by scientists at...

Read Article