Tips For Reducing Water Use In Nebraska Irrigation

Nebraska irrigated agriculture sits at the intersection of high-value production and finite water resources. With a large portion of irrigation drawing from the High Plains (Ogallala) Aquifer and surface water tied to river basins and Natural Resources District (NRD) management plans, producers need practical strategies to reduce water use while maintaining yields and profitability. This article provides concrete, field-tested techniques, equipment upgrades, monitoring practices, and implementation steps tailored to Nebraska conditions.

Know your water supply, legal limits, and monitoring requirements

Before changing systems or management, document the physical and legal constraints that govern your water use.

• Determine source and permitted volumes: confirm well locations, permitted extraction rates, and any NRD-imposed allocation limits or required meters.
• Understand local rules: many NRDs in Nebraska have groundwater management areas, phases, or rules that change allowable pumping, require reports, or offer cost-share. Contact your NRD office to confirm current rules and incentive programs.
• Baseline water accounting: establish a reliable baseline by installing or verifying flow meters and keeping a simple log of weekly or monthly pumped volumes. Accurate historic use is necessary to evaluate savings.

Measure and monitor: the foundation of water reduction

Good decisions start with data. Invest first in measurement and monitoring to guide changes.

• Flow meters and totalizers: install calibrated flow meters on pumps and pivots to log volume per hour and acre-inch applied. Combine with a simple totalizer and periodic calibration checks.
• Soil moisture monitoring: deploy soil moisture sensors across representative zones in each field. Options include time-domain reflectometry (TDR), capacitance sensors, or simple manual probes. Sensors should measure at multiple depths (e.g., 6, 12, 24 inches) to capture the crop rooting zone.
• Weather-based ET: use local weather station data or county-level evapotranspiration (ETo) estimates to calculate crop water use (ETc = ETo x Kc). Incorporate daily or weekly ET into scheduling decisions.
• Telemetry and logging: wherever possible, use telemetry to centralize sensor and meter data. Real-time access reduces response lag and supports precision irrigation.

Improve irrigation scheduling

Scheduling is the single biggest behavioral change that reduces water use without new hardware outlays.

• Schedule to soil moisture and crop demand: irrigate when the crop depletion approaches a pre-determined threshold (e.g., 50-60% of plant available water depleted for many row crops), not on fixed calendar intervals.
• Use ET-based calculations: compute weekly water need as ETc minus effective rainfall and make application decisions based on measured soil moisture.
• Avoid deep percolation: apply only the water the crop can use before the next irrigation window. Overapplication wastes water via deep percolation and can mobilize salts or nitrates.
• Night versus day applications: for sprinklers, nighttime applications reduce evaporative losses but can increase disease pressure in some crops; weigh trade-offs by crop.

Upgrade irrigation hardware strategically

Target system improvements that deliver the largest water savings per dollar spent.

Center pivots and laterals

• Low-energy precision application (LEPA) and drop tubes: LEPA or drop nozzles reduce evaporation and wind drift by delivering water near the canopy or ground. Converting a conventional pivot to LEPA or installing drop hoses can cut irrigation requirement significantly in many conditions.
• Low-pressure nozzles and regulators: install matched nozzle packages and pressure regulators to maintain uniform application at reduced pressure, improving distribution uniformity and reducing wind drift.
• End gun management: disable end guns when not necessary; they often reduce uniformity and waste water on outer corners that are less productive.
• Variable rate irrigation (VRI): VRI allows applying different rates across the pivot path to match soil texture, topography, and yield potential. When combined with soil maps and yield maps, VRI targets water where it yields greatest return.

Surface irrigation (furrow, flood)

• Laser leveling: accurate leveling reduces ponding and tailwater, improving uniformity and reducing applied depth needed.
• Surge irrigation and gated pipe: surge or pulsed furrow irrigation improves infiltration distribution on many soils. Gated pipe enables faster, more uniform flows while reducing labor.
• Tailwater recovery: construct small catchment ponds and reuse systems to capture runoff and pump it back for reuse. This reduces net external water demand and prevents nutrient runoff.

Drip and subsurface drip irrigation (SDI)

• High efficiency: drip and SDI systems deliver water directly to the root zone, often achieving high water-use efficiency. These systems perform well in vegetable, specialty crops, and some high-value row crops.
• Cost and maintenance: SDI requires upfront investment, regular flushing, filtration, and protection from root intrusion. Evaluate economic return based on crop value and water savings.

Manage soils and crops to conserve water

Soil and crop management practices complement irrigation changes and often deliver ongoing benefits.

• Increase soil organic matter: practices that build organic matter (cover crops, reduced tillage, manure applications) increase water-holding capacity, reducing irrigation frequency.
• Conservation tillage and residue management: leaving residue on the surface reduces evaporation and improves infiltration, especially important during hot, dry periods.
• Match crops to water availability: consider crop selection, hybrid maturity, and planting dates to align crop water demand with available supply. For example, switching to shorter-season hybrids can reduce peak-season water demand in constrained years.
• Use gap-filling crops and cover crops carefully: select cover crops that improve soil structure without substantially increasing summer water demand on limited water budgets.

Maintain pumps and conveyance to minimize losses

Mechanical efficiency affects water use as much as application uniformity.

• Pump efficiency audits: periodically test pump curves, check motor efficiency, and consider variable frequency drives (VFDs) to match pump speed to required flow, often saving energy and reducing wasted flow.
• Leak detection and repair: check pipelines, fittings, and seals annually. Small leaks compound into significant water loss over a season.
• Pressure management: excessive pressure increases evaporation and drift on sprinklers and causes uneven application. Use pressure regulators and properly sized pipe.

Field-scale technologies that pay in Nebraska

Prioritize technologies that have proven return on investment under local conditions.

• Soil maps and yield maps: develop management zones using soil surveys and historical yield data to guide VRI prescriptions.
• Remote sensing and aerial imagery: use NDVI or similar indices from drones or satellites to detect stress early and refine irrigation targeting.
• Decision support tools: integrate ET estimates, sensor data, and weather forecasts to make data-driven irrigation decisions.
• On-farm demonstration: pilot new technologies on a small portion of a field before whole-farm adoption to measure real water and yield impacts locally.

Financial tools, incentives, and regulatory considerations

Nebraska has multiple local and federal programs that can assist with adoption.

• NRD cost-share and incentive programs: many NRDs offer cost-share or technical assistance for efficient irrigation equipment, meters, and conservation practices. Check with your local NRD for current offerings.
• Federal programs: USDA conservation programs may provide cost-share for irrigation efficiency projects, cover cropping, and soil health practices. Eligibility and rules change, so consult your local service center.
• Water banking and transfer mechanisms: in some basins, water banking or temporary transfers are options for reallocating conserved water. Work with NRDs and legal counsel to understand requirements.

Implementation roadmap: step-by-step

1. Conduct a water use audit: install or verify flow meters and collect one full season of data.
2. Prioritize low-cost changes: fix leaks, adjust schedules, turn off end guns, and adjust nozzle packages.
3. Deploy monitoring: install soil sensors in representative zones and set up an ET-based schedule system.
4. Pilot hardware upgrades: test LEPA/drop tubes, surge irrigation, or VRI on a small scale.
5. Evaluate economics: compare yield, energy, and water savings against costs to guide larger investments.
6. Scale up based on data: expand successful pilots field-by-field, using mapping and remote sensing to refine prescriptions.

Practical takeaways and metrics to track

• Track acre-inches applied per field and compare to crop water use estimates. Aim to reduce the gap between applied depth and crop evapotranspiration without hurting yield.
• Monitor distribution uniformity (DU/CU) for sprinkler systems; improving uniformity often reduces required depth.
• Calculate water use efficiency in yield per acre-inch. If yield per unit water increases, changes are effective even if applied water is only modestly reduced.
• Keep a seasonal ledger of pumping hours, kilowatt-hours, and water volume to evaluate energy-water trade-offs.

Reducing water use in Nebraska irrigation is both a technical and managerial exercise. The most effective programs combine reliable measurement, focused scheduling, targeted hardware upgrades, and soil/crop management. Start with monitoring and low-cost fixes, pilot technologies in representative fields, and scale investments based on measured water and yield responses. With thoughtful implementation, many Nebraska producers can conserve significant water resources while protecting farm profitability and long-term productivity.