Gold Creek Return Flow Pilot Study: Evaluating Potential Benefits of Early Season Center Pivot Irrigation on Local Hydrology and Production

Project Overview

FW24-015
Project Type: Farmer/Rancher
Funds awarded in 2024: $25,000.00
Projected End Date: 03/15/2027
Host Institution Award ID: G251-24-WA507
Grant Recipient: Thomas Herefords
Region: Western
State: Montana
Principal Investigator:
Bruce Thomas
Thomas Herefords

Commodities

  • Agronomic: grass (misc. perennial), hay, medics/alfalfa

Practices

  • Crop Production: irrigation, water management
  • Education and Training: on-farm/ranch research

    Proposal summary:

    A “paradox” of irrigation efficiency has developed during the
    widespread conversion of irrigation methodology, from flooding of
    fields to pipes and sprinklers. The former diverts a greater
    volume of water, but much of it is not consumed; unconsumed can
    then enter the shallow groundwater and travel to the creek over
    the summer months (return flows). Sprinkler methods divert much
    less water, but consumption is higher, so less water percolates
    through the soil profile and back to the creek. Potential impacts
    of this conversion include: reduced late-season return flows,
    shallower rooting zones, and reduced productivity, especially
    regrowth after the first cutting. All of these have implications
    for soil health, streamflow, and farm profitability. The research
    question posed is, “Can the hydrologic, soil, and agricultural
    benefits of flood irrigation be captured by modifying the
    early-season application of a center pivot to deliver a higher
    volume of water?”

    We expect that modifying the sprinkler technique will increase
    late-season return flows, soil moisture at depth, and
    productivity (hay produced and regrowth). Maintaining late-season
    return flows will provide more water to downstream irrigators and
    lessen the likelihood of senior users making water calls on
    juniors. Increased soil moisture will stimulate root growth and
    microbial activity to enhance soil health and sustainability.
    Overall productivity will increase, resulting in greater
    profitability. Results from this project will advance sustainable
    agriculture by providing a comprehensive suite of monitoring data
    (hydrology, soil moisture and infiltration, surface water
    quality, agricultural productivity) to share with other producers
    and agricultural professionals. Projects results will be
    disseminated to the local community and producers through meeting
    presentations and a ranch tour (publicized through social media,
    press release, and newsletters). A 2-page handout will be
    produced for distribution, and results will be conveyed to the
    scientific community at a professional water resources meeting
    and/or journal article.

    Project objectives from proposal:

    Research
    Objectives

    Objective 1. Demonstrate the feasibility of modified irrigation
    technique.

    Objective 2. Quantify effects of modified irrigation technique on
    the hydrology, soil, and agricultural production and develop
    ranch-scale water balance.

    Objective 3. Synthesize results for dissemination.

    Education
    Objectives

    Objective 1. Share project results with local producers and
    agricultural professionals through presentations at regular
    meetings and statewide conventions.

    Objective 2. Host ranch tour to share results with local
    community, producers, and agricultural professionals.

    Objective 3. Disseminate results to academic and professional
    communities through conference presentation and/or publication in
    a peer-reviewed or professional journal.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.