• Red Rocks with water in front of them in the desert.
  • Clouds behind Joshua Tree and bushes.
  • Desert flowers blooming in bushes in front of mountains in the desert.
  • Setting sun reflecting of clouds of orange and blue behind a joshua tree.
  • Hoover Dam intake towers with water behind the dam showing that it is not full.


Managing water and riparian habitats on the Bill Williams River with scientific benefit for other desert river systems

Science Need(s)

Critical Management Question 1: Water Management and Climate Change
How are climate change, water management, and their interaction affecting the physical processes that support springs, aquatic and riparian habitats, species, and human cultures? What are viable management options to mitigate these effects and support ecosystem functions? How can climate change, hydrological, ecological, and/or biological models be used to better understand the potential future effects of climate change, inform adaptive management and development of beneficial management practices, and create related decision support tools?

Critical Management Question 2: Monitoring Species/Processes and Related Threats/Stressors
What species and ecological processes are sensitive to climate change and/or other large scale stressors (e.g., water management, invasive species, altered fire regime, wind erosion) and can be effectively monitored to indicate the overall effects of these stressors on ecosystems, habitats, and species, thus helping managers detect, understand, and respond to these changes? What are the best monitoring designs and protocols to detect changes to these processes and species at temporal and geographic scales suitable for providing adequate and reliable metrics?


Grantee: US Army Corps of Engineers
Principle Investigators: John Hickey (UACE), Andrew Hautzinger (USFWS), Steven Sesnie (USFWS), Patrick Shafroth (USGS),
Dick Gilbert (Bill Williams River National Wildlife Refuge)
Cooperative Agreement:  $128,000 in matching funds and $95,000 in Federal funds provided by Bureau of Reclamation
Project Duration: 2013-2015
Project Goal(s)

  1. Codify flow-ecology relationships for riparian species of the Bill Williams River as operational rules for water managers.
  2. Test rules under different climate scenarios.
  3. Revise rules as needed to mitigate the effects of climate change such that rules will allow responsible and adaptive management of water and riparian habitats.

Brief Project Description

U.S. Army Corps of Engineers Hydrologic Engineering Center will work with the U.S. Fish and Wildlife Service and U.S. Geological Survey to develop new operational rules for water managers to guide reservoir releases to promote the establishment of native cottonwood and willow stands downstream of reservoirs while balancing other water management needs. Once completed, project benefits will be transferable to other managed river systems in the arid southwest.

Project Location

Bill Williams River

Project Tasks

  1. Preparation of hydrologic scenarios
  2. Acquisition of raw LIDAR data
  3. Model simulations for existing conditions
  4. Post-processing of model results to formulate operational rule
  5. Simulations for all hydro scenarios
  6. Finalization of rule and coordination with operators
  7. Coding and testing of habitat mosaic feature in EFM
  8. LiDAR data processing

Project Deliverables

  1. Hydrologic data sets for different climate conditions
  2. Digital elevation model, spatial layer describing current vegetation
  3. Simulated extents of riparian seedling establishment areas
  4. Manuscript describing technologies to operationalize flow-ecology relationships
  5. Rule and supporting guidance for integration with operational policies
  6. Tech transfer and presentation at meetings

Opportunities to learn more

Documents for downloading

Project Proposal