Agricultural Irrigation Well Cost

Why irrigation wells are a different scale problem than residential wells

Residential wells are sized for a household: 200 to 500 gallons per day average, 8 to 12 gpm peak. Irrigation wells are sized for an acreage: a typical 40-acre row-crop quarter-pivot uses 200 to 800 gallons per minute continuously for 12 to 24 hour irrigation cycles. The pump moves more water in one hour than a residential well moves in two weeks. Everything downstream of "drill a hole in the ground" scales up.

The casing diameter is the first visible difference. A 6-inch residential casing can support a 1 to 5 HP submersible pump and 5 to 25 gpm peak yield. An 8-inch ag casing supports 5 to 25 HP turbine pumps at 100 to 400 gpm. A 12-inch casing supports 25 to 100 HP turbines at 400 to 1,500 gpm. The casing has to be bigger because the pump motor and bowl assembly have to physically fit inside it; a 50 HP turbine bowl assembly is about 7 inches in diameter and needs 8 to 10 inches of clearance.

The pump configuration is the second visible difference. Most ag wells use line-shaft turbine pumps rather than submersible pumps. A turbine pump has the motor at the wellhead driving a vertical shaft down to the bowls in the producing zone; the bowls (multi-stage centrifugal impellers) lift the water up the casing. The motor is air-cooled at the surface and can be serviced without pulling the bowls. Turbine pumps are more expensive than submersibles ($8,000 to $30,000 for the pump assembly, plus $5,000 to $20,000 for the motor) but they are more efficient at the high flow rates and longer service lives that ag wells demand.

The third difference is electrical service. A 50 HP three-phase 460V pump motor draws around 60 amps under load. Most farm and ranch sites do not have 460V service at the well location; the install may include a transformer ($5,000 to $15,000), trenching for primary electrical service ($5 to $20 per linear foot), and a motor-control centre with variable-frequency drive ($8,000 to $25,000). The electrical-install line item on a row-crop irrigation well bid can easily exceed the drilling cost itself.

Cost breakdown for a representative row-crop well

Take a 600-foot 12-inch irrigation well in the Ogallala-overlying region of western Kansas, drilled to supply a 130-acre quarter-pivot at design flow of 750 gpm. The bore is drilled at 17 inches through the upper 60 feet of soft sediment to set 12-inch surface casing; the remaining 540 feet is drilled at 14 inches through Ogallala sand-and-gravel and underlying Permian sediments. The 12-inch casing is set the full 600 feet (perforated stainless-steel screen across the productive zone in the bottom 100 feet), with gravel pack around the screen.

Line items at 2026 rates. Mobilisation (heavy-rotary rig with 14-inch bit capacity) $3,000. Drilling 60 feet at 17 inches through soft sediment $4,000. Drilling 540 feet at 14 inches through Ogallala and Permian at $80 per foot ($43,200). Twelve-inch steel casing 500 feet at $35 per foot installed ($17,500). Stainless-steel well screen 100 feet at $120 per foot ($12,000). Gravel pack 100 feet, $4,500. Grouting (cement) 60 feet, $1,500. Well cap and surface seal, $800. Development 24 hours (bailing, surging, airlift), $4,000. Vertical turbine pump 75 HP, 750 gpm, 10-stage bowl assembly $18,000. Line shaft and column pipe 540 feet, $9,500. Pump motor 75 HP 460V three-phase $9,000. Motor control with variable-frequency drive $14,000. Electrical service install (transformer and 800 feet of primary cable) $18,000. Concrete pump pad $2,500. Wellhead piping and discharge plumbing to pivot $6,000. State permit and water-rights filing $4,500. Subtotal: $172,000. With 10 percent contingency, $189,200.

That looks high compared to a residential well, but per-acre-foot of irrigation capacity it is roughly equivalent to other irrigation infrastructure. The well is amortised over 25 to 40 years; if it supports 130 acres of row crop generating $400 to $900 per acre in annual net margin, the well pays back its capital cost in 2 to 4 years and operates for decades after that.

Per-acre-inch operating economics

The metric that matters for ongoing operations is the cost per acre-inch of water pumped. An acre-inch is approximately 27,150 gallons. A typical row crop (corn, soybean, sorghum) needs 12 to 24 acre-inches of supplemental irrigation per growing season, depending on rainfall and soil. A well delivering 750 gpm pumps one acre-inch every 36 minutes; 12 acre-inches over a 130-acre quarter takes about 78 hours of pump time per inch of supplemental water.

Electricity dominates the operating cost. A 75 HP motor at 90 percent loading draws about 55 kW. At $0.10 per kWh, the cost is $5.50 per hour or $1.65 per acre-inch pumped. At $0.18 per kWh (higher western utility rates), it is $3.00 per acre-inch. Add wellhead and pump maintenance ($1,200 to $3,000 per year), and the marginal operating cost is roughly $2 to $4 per acre-inch.

Capital recovery is the second component. On a $190,000 well amortised over 30 years at 6 percent, the annual capital cost is about $13,800. If the well supports 130 acres at 18 acre-inches per acre per year (2,340 acre-inches), the capital cost adds $5.90 per acre-inch. Total all-in cost: $8 to $10 per acre-inch. That is the number to benchmark against alternatives (surface-water rights, neighbouring well share, deficit irrigation) when deciding whether the well is the right investment.

Water rights and the permit process

In western states, drilling an agricultural well is half a drilling project and half a water-rights project. The pump capacity has to be approved before the bore can be drilled, and in most states the water right is granted in the name of the landowner with seniority dating from the application. Senior rights take precedence in dry years; junior rights may be curtailed.

California (SGMA-adopted basins). Most of the Central Valley is now under Sustainable Groundwater Management Act allocations administered by local Groundwater Sustainability Agencies. New agricultural wells require GSA approval and may receive an annual pumping allocation that limits production. The drilling permit alone runs $500 to $2,500; the water-rights work (engineering studies, GSA application, possible public hearing) can add $5,000 to $30,000 to the project.

Arizona (AMA zones). Active Management Areas (Phoenix, Tucson, Pinal, Prescott, Santa Cruz) strictly limit new agricultural wells. New wells in these zones must demonstrate that they will not interfere with existing wells and may be subject to a strict pumping cap. ADWR permit and review process typically $1,500 to $5,000 with 6 to 12 month timeline.

Texas (Groundwater Conservation Districts). About 100 GCDs across the state, with widely varying rules. Districts typically require well registration, often metering and annual reporting. Permit fees $200 to $2,000. Some districts cap pumping per acre or per well; some do not.

Plains states (Kansas, Nebraska, Colorado, Wyoming). State engineer or water-resources office approval required. In Kansas, GMD-set caps apply in some districts. In Nebraska, NRD-set caps apply in over-appropriated basins. Permit fees $200 to $1,500; water-rights work for new appropriations may be $3,000 to $15,000.

USDA NRCS EQIP cost-share for irrigation wells

The Environmental Quality Incentives Program is the primary federal cost-share mechanism for agricultural water infrastructure. It does not pay for new groundwater development as such, but it does pay for irrigation-efficiency improvements that often include a new well as a component (replacing an old leaking flood-irrigation system with a new well-fed centre-pivot, for example, qualifies as an efficiency improvement).

Cost-share rates vary 50 to 75 percent of eligible project cost depending on the conservation outcome and the producer's classification (limited-resource, beginning, socially disadvantaged farmers receive higher rates). On a $190,000 row-crop well project, a 50 percent EQIP cost-share would offset $95,000 of the cost, transforming the per-acre-inch capital recovery from $5.90 to $3.00.

Application timing matters. EQIP runs on annual ranking and approval cycles managed by the local NRCS office and the state technical committee; applications submitted in January are typically approved (or not) by May, with construction-eligible windows starting after the approval letter. Producers planning to drill in 2026 should have applied in late 2025; producers planning for 2027 should be assembling the application now. Contact the local NRCS field office for state-specific eligibility and the current technical guide.

Cross-references and related pages

For the per-foot drilling rate that underlies the cost above, well drilling cost per foot 2026. For livestock-watering well economics (smaller pump, similar bore), livestock water well cost. For commercial-application wells (hotel, golf, RV park), commercial water well cost. For state-specific permitting context relevant to ag wells, California well drilling cost, Arizona, Texas. For the deep-well drilling penalties relevant to row-crop wells in declining-water-table regions, 800-foot well drilling cost.