How To Reduce Water Use In Kansas Irrigation Systems

Water is the lifeblood of Kansas agriculture, but many parts of the state face declining groundwater levels, increasing demand, and variable precipitation. Reducing irrigation water use is both an economic necessity and a stewardship responsibility. This article provides practical, field-tested strategies to lower water consumption in Kansas irrigation systems without compromising yield potential when possible. Concrete metrics, step-by-step actions, and performance benchmarks are included so operators, managers, and producers can make informed decisions.

Kansas water context and why reduction matters

Kansas relies heavily on the High Plains (Ogallala) aquifer in the western and central portions of the state and on alluvial and other shallow aquifers elsewhere. In many counties groundwater levels have declined for decades, reducing well yields, increasing pumping costs, and shortening well lifespans. Surface water supplies are variable, subject to storage limits and legal allocations.
Reducing irrigation use addresses three key risks:

Prolonging aquifer life and maintaining future water availability.
Reducing energy and pumping costs.
Improving system resilience to drought and regulatory change.

Understanding local water availability, water rights, and conservation district rules is the first step before making changes to irrigation strategy.

Measure first: know how much water you use

You cannot manage what you do not measure. Start with a comprehensive audit of water use and system performance.

Install and verify accurate flow meters on every pumping unit and pivot. Calibrate annually and log totals.
Record application depth per irrigation event in inches or millimeters. Convert totals to gallons using 1 acre-inch = 27,154 gallons.
Determine application uniformity: Distribution Uniformity (DU) for sprinklers and Drip Uniformity (DU) or Christiansen Coefficient for other systems. Aim for DU > 80% for sprinklers and > 85% for drip.
Track energy use per acre-inch pumped to calculate cost-per-inch and evaluate pump efficiency.

A simple baseline example: a 160-acre field receiving 12 inches over a season uses roughly 160 x 12 x 27,154 = 52,152,960 gallons. Small percentage savings become large volume reductions.

Choose the right irrigation method for the field

Irrigation system selection determines the theoretical maximum efficiency and practical water use.

Typical application efficiencies and expected savings

Flood and furrow: application efficiency 50-65%. Large losses to deep percolation and runoff are common if not managed.
Conventional sprinkler (hand-move, solid-set): 70-85% depending on pressure, nozzle condition, and uniformity.
Center pivot with mid-elevation or low-elevation spray application: 80-90% with good maintenance and proper nozzle selection.
Low Energy Precision Application (LEPA) and subsurface drip irrigation (SDI): 85-95% or higher when correctly designed and maintained.

Switching from flood irrigation to sprinkler or drip can reduce consumptive use by 20-50% on many soils, but conversion costs and management intensity must be considered.

Field-level considerations

Soil texture, slope, and drainage control what is practical:

Coarse-textured sandy soils hold less plant-available water and require more frequent irrigation but have lower deep percolation risk if scheduled correctly.
Fine-textured clays hold more water but have slower infiltration; surface methods risk runoff and uneven distribution.
Variable topography and soil variability favor variable-rate irrigation solutions to tailor application to sub-field needs.

Irrigation scheduling: make every drop count

Scheduling is the most direct method to cut water use. Replace calendar or “every X days” scheduling with demand-based scheduling.

Use crop water demand metrics

Reference evapotranspiration (ETo) driven by local weather is the basis for crop water use estimates. Multiply ETo by the crop coefficient (Kc) to get crop evapotranspiration (ETc = ETo x Kc).
Maintain a soil water balance or use soil moisture sensors to determine when to irrigate. Common practice is to refill the crop root zone to a predetermined fraction of available water (e.g., refill when soil water is depleted to 40-60% of plant-available water for many crops).
Implement deficit or regulated deficit irrigation where economically justified: intentionally apply less water than full ETc at certain growth stages to save water without major yield penalty (common in sorghum, some corn, and wheat).

Practical scheduling tools and sensors

Tensiometers and electrical resistance or capacitance probes give real-time soil moisture information. Place sensors at representative locations and depths corresponding to the active root zone.
Electronic controllers and telemetry can integrate ETo, Kc, and soil moisture to automate irrigation events.
Use a combination of remote weather-based ETo stations and in-field soil sensors for best performance, especially on large or variable fields.

Reduce conveyance and application losses

Conveyance losses in open ditches and leaks in piping add up quickly. Take these steps:

Line or pipe open canals and ditches where feasible. Piping eliminates seepage and reduces evaporation and authorized losses.
Repair leaks promptly and auditorily inspect hydrants, valves, and seals on a seasonal basis.
Match pump discharge pressure to the irrigation system requirements. Excessive pressure increases wind drift and evaporation.
Install pressure regulators, uniform nozzles, and maintain proper nozzle sizes and spacing on pivots. Replace worn nozzles and check for clogged or damaged emitters in drip systems.

Simple maintenance can improve system efficiency by several percent and reduce unnecessary pumping.

Advanced technologies to stretch water

Invest in technologies that have demonstrable return on investment for your operation.

Subsurface drip irrigation (SDI): Places water in the root zone and greatly reduces evaporation and deep percolation. Installation cost is high but per-acre water savings can be 20-50% depending on the baseline.
Variable rate irrigation (VRI): Controls application depth across a pivot to match soil and crop variability. Helps avoid over-watering wet or shallow-soil zones.
Low-pressure, low-angle sprinklers and LEPA on center pivots: Reduce losses to drift and evaporation compared with high-elevation sprays.
Automated control with telemetry: Reduces human lag in applying irrigations at optimal times and integrates soil and weather data.

Evaluate capital cost, expected water and energy savings, and maintenance requirements. Small farms may prioritize lower-cost scheduling and maintenance changes before large capital investments.

Crop and soil management practices that reduce irrigation need

Agronomic decisions can reduce consumptive water demand and make irrigation more efficient.

Choose drought-tolerant varieties and hybrids when available and suitable for market goals.
Use crop rotations that improve water use efficiency and soil structure, such as including deep-rooted crops or cover crops where appropriate.
Minimize deep tillage that destroys soil structure and porosity. Conservation tillage and residue cover reduce evaporation from the soil surface.
Incorporate cover crops and residue management to enhance infiltration, reduce runoff, and increase soil organic matter, which raises available water holding capacity.
Time plantings to match water availability windows and avoid irrigating late-season stages when water use efficiency is low relative to yield response.

These practices often provide co-benefits such as improved soil health, lower fuel costs, and reduced erosion.

Economic and regulatory considerations

Reducing water use typically lowers energy and pumping cost, but capital investments require business planning.

Run a simple payback analysis: calculate annual water and energy savings (gallons saved x energy cost per gallon pumped) and divide capital cost by annual savings to estimate years to payback.
Seek cost-share and incentive programs available through federal or state conservation programs and local districts. Many programs prioritize conversions to efficient systems and practices that conserve groundwater.
Understand local water management rules. Groundwater management districts (GMDs) and irrigation districts in Kansas may have regulatory programs, water use reporting, or conservation requirements.

Consider water savings in the context of expected crop revenue, input costs, and long-term availability of water for the farm.

Monitoring, verification, and continuous improvement

Conservation is iterative. Implement a monitoring plan and set measurable targets.

Establish baseline metrics: seasonal acre-inches applied, energy use per acre-inch, and system DU.
Set specific reduction targets: for example, reduce seasonal water use 15% in two years or improve DU to 85% within one season.
Measure progress monthly and after each irrigation season. Compare yield and quality to ensure water reductions do not produce unacceptable yield loss.
Adjust practices: change scheduling thresholds, repair systems, or invest in new technology based on measured outcomes.

Verification builds confidence in practices that work and provides data for grant applications and neighbor education.

Field checklist: immediate actions to reduce water use this season

Install or confirm calibration of flow meters on all pumps.
Conduct a pre-season pressure and nozzle check on pivots and sprinklers; replace worn parts.
Implement soil moisture sensors in representative fields and use a simple refill threshold (example: refill when soil water is at 50% of available water).
Repair leaks and pipeline losses before the irrigation season starts.
Reduce tailwater losses by adjusting furrow practices, employing surge irrigation where appropriate, or converting to gated pipe.
Review crop hybrid and variety choices for drought performance and consider adjusting planting dates to reduce peak water demand during hot, dry periods.

Final takeaways

Start with measurement: accurate metering and DU testing guide every other decision.
Scheduling based on ETo and soil moisture reduces wasted water more than any single hardware change.
System maintenance yields quick, low-cost gains; technology upgrades give larger, longer-term savings.
Agronomic adjustments and soil health improvements reduce the crop demand side of the equation and complement irrigation improvements.
Evaluate economics and available cost-share before large investments; many conservation measures pay back through energy and water savings.

Adopting a layered approach that combines better measurement, smarter scheduling, targeted system upgrades, and agronomic improvements will deliver the most reliable water reductions. In Kansas, where aquifer health and farm viability are tightly linked, managing irrigation water efficiently is essential for the next generation of production.