Calculate the total cost to apply one acre-inch of irrigation water including energy, maintenance, labor, and water charges for budget planning.
The cost to apply one acre-inch of irrigation water is a key metric for farm budgeting and irrigation investment decisions. It includes energy costs (electricity, diesel, or natural gas) to run the pump, maintenance and repair of equipment, labor for system operation, and any water purchase or delivery charges.
Knowing your cost per acre-inch lets you calculate the total irrigation expense for the season, compare the economics of different crops and irrigation methods, and determine when deficit irrigation or dryland farming becomes more profitable.
This calculator sums up the main cost components and divides by your seasonal application volume to give you a per-acre-inch cost you can plug into crop budgets. Whether you are a beginner or experienced professional, this free online tool provides instant, reliable results without manual computation. By automating the calculation, you save time and reduce the risk of costly errors in your planning and decision-making process.
Irrigation is often the largest variable cost in crop production. Knowing your cost per acre-inch helps you make smarter decisions about how much to irrigate, which crops to grow, and whether system upgrades pay for themselves. Having a precise figure at your fingertips empowers better planning and more confident decisions.
Cost per Acre-Inch = (Energy + Maintenance + Labor + Water Charges) / Total Acre-Inches Applied
Result: $5.00 per acre-inch
Total cost = $8,000 + $2,000 + $1,500 + $1,000 = $12,500. Divided by 2,500 ac-in applied = $5.00/ac-in. For a 125-acre pivot applying 20 in/season, that is $12,500 for the season.
Energy costs depend on three factors: total dynamic head (TDH), pump and motor efficiency, and the energy rate. Increasing pump efficiency by just 5% (e.g., from 65% to 70%) reduces energy cost by about 7%. Annual pump tests identify efficiency degradation.
Electricity, natural gas, diesel, and propane are the main pump fuels. At typical 2025 rates, electricity is usually cheapest per kWh-equivalent, followed by natural gas, then diesel/propane. Variable rate electric plans with off-peak irrigation discounts offer additional savings.
Multiply cost per ac-in by total seasonal application to get irrigation cost per acre. Compare this with yield response curves: the last few inches of irrigation may cost more than the additional revenue they generate, especially for crops with diminishing returns to water.
Costs vary widely: $2–$4/ac-in for efficient electric wells, $5–$8/ac-in for diesel or deep wells, and $8–$15/ac-in for high-lift or distant water sources. Your actual cost depends heavily on energy prices, pumping depth, and system efficiency. Tracking your cost over several seasons helps identify trends and opportunities for savings.
Energy cost = kWh per ac-in × electricity rate. For typical center-pivot conditions, 20–50 kWh per ac-in at $0.08–$0.12/kWh gives $1.60–$6.00/ac-in for energy alone.
This calculator focuses on variable (operating) costs. Fixed costs like depreciation and insurance are important for investment analysis but are usually separate from per-acre-inch operating costs.
Deeper wells require more energy per gallon pumped. Total dynamic head (TDH) is the key variable: energy cost is proportional to TDH. A well pumping from 200 ft costs roughly twice as much per ac-in as one from 100 ft.
Districts charge per acre-foot, per acre, or both. Include only the variable portion (per ac-ft charge) in your per-acre-inch calculation.
Improve system efficiency (less gross water per net inch), switch to off-peak electricity rates, maintain pumps for peak efficiency, and use soil moisture sensors to avoid unnecessary irrigations. Scheduling irrigations based on crop water demand rather than a fixed calendar can reduce water use by 10–20%. Regular pump testing ensures your equipment is operating at optimal efficiency and not wasting energy.