AWRA 2011 SUMMER SPECIALTY CONFERENCE Snowbird, Utah
June 28, 2011
Presenters: Amy Verbeten, Veronica Orosz Co-Authors: Rob Van Kirk, J. Mark Baker, Yvonne Everett, Lora Liegel, Kimberly Peterson, Brian Apple
Overview Study Area
Research Objectives & Methods
Findings
Action Steps
This research was funded by: U.S. Department of Agriculture Cooperative State Research, Education, and
Extension Service grant number 2008-51130-19555
For more information, go to: www.humboldt.edu/henrysfork
Henry’s Fork Watershed ID/WY border
Arid to semi-arid climate
3,200 sq. mi.
Population: 50,000
Irrigated agriculture has dominated land use since 1900
Irrigated Agriculture Late 1800s: European settlement and agriculture
Earthen canals developed to transport surface water (250,000 acres irrigated by 460 miles of canals)
Pre-1960s, water was applied by flooding fields
1970s-1990s: Conversion to sprinkler systems
Development of irrigated lands Residential
development on land previously irrigated by canal systems
Limited scale watershed-wide, but high local concentrations
Development is highly fragmented
Research Objectives & Methods Calculate canal system water budget & quantify
effects of changing water management
Field measurement of canal seepage
Hydrologic analysis & modeling
GIS analysis
Identify mechanisms & create tools to manage hydrologic impacts of development
Stakeholder interviews
Develop educational materials
Work with watershed council to develop management strategy
Results: Surface Flow Mean number of days of continuous surface flow in losing reach of Teton Creek under varying irrigation practices
Changes in irrigation practices have a substantial effect on surface water supply
Diversion of water into canals alters hydrology of streams
Increases in efficiency decrease diversion
Natural hydrology supports riparian vegetation and native species
Results: Groundwater Recharge Total basin-wide groundwater recharge under varying irrigation practices
Changes in irrigation practices have a substantial effect on groundwater levels
Canal seepage is the single largest contributor to groundwater recharge
Increases in efficiency decrease aquifer recharge
Groundwater recharge acts as a storage mechanism, provides water for down-gradient irrigators, and supports spring-dependent wetlands and habitat
Results: Water Use & Management
Canal system not designed to irrigate small parcels
Fragmentation makes it difficult for remaining farmers to flood or sub-irrigate
Availability of surface water doesn’t guarantee use
Increase in domestic wells
Increasing groundwater withdrawal + decreasing recharge
Results: Water Use & Management
Lack of communication between water managers & land planners
Canal companies face monetary and physical challenges in urbanizing landscape
Land use planning and water management values & priorities vary by county
Hydrologic changes not
intentional – they “just happen” Responsibility for management
decisions falls disproportionately on canal companies
Hydrologic & Sociologic Implications Changes in irrigation practices lead to hydrologic changes that
impact humans and ecological processes
Management responsibility currently falls on canal companies, which lack resources to proactively manage this change
To manage proactively, local land use planners, agricultural irrigators, canal company managers, subdivision residents, homeowners associations, and developers need to work together to conjunctively manage ground and surface water
Choice of future water management actions will depend on understanding of local hydrogeology, stakeholder values, and effects on downstream water rights holders & native species
Action Step: Develop targeted educational materials in order to • Increase understanding of impacts of water
management changes • Increase communication between water managers
and land planners • Introduce tools for managing hydrologic impacts
of development
Action Step: Develop targeted educational materials
Identify Target Audiences
“New” Water Users
Local Decision Makers
Canal Companies
Identify Overall Messages
Water Cycle – Ground and surface water interactions
Changes to the landscape have impacts on the aquifer and streams
Enhance communication between the three audiences to plan for these changes
Educational Materials Cont. Identify Target Messages
“New” Water Users
Know about water rights
Realize that your water usage has impacts on the entire system – human and natural
Local Decision Makers
Communicate with canal companies
Plan for the impacts of development on water resources
Canal Companies
Ensure that assessments cover increased operating costs
Work with shareholders to balance aquifer recharge and streamflow
Educational Materials Cont.
Delivery Mechanisms
Booklet
Brochure
Project Website
Future Work: Work with Henry’s Fork Watershed Council to develop management strategy
Questions?