Know Your Borewell’s True Capacity Before You Plant a Single Seed
For millions of farmers across India, Africa, Australia, the Middle East, and the Americas, a borewell is not just a hole in the ground — it is the lifeline of the entire farm. When the monsoon fails, when the canal runs dry, when the river drops to a trickle, the borewell is what stands between a successful harvest and a total crop loss.
But here is the problem most farmers face: they drill a borewell, the driller tells them “good yield,” they install a pump — and then discover mid-season that the water runs out after just a few hours of pumping. The crops suffer, the yield drops, and the investment is wasted.
The root cause of this problem is almost always the same: nobody calculated whether the borewell’s actual yield was enough to meet the farm’s actual water demand.
Our Borewell Yield Estimator solves this problem. It helps you measure your borewell’s true yield from field test data, compare it against your irrigation demand, analyze your aquifer’s recovery rate, and calculate a sustainable pumping schedule — all in one place, with support for metric and imperial units.
🌊 Borewell Yield Estimator
Estimate your borewell’s water yield (LPH / GPH), check if it meets your farm’s irrigation demand, calculate sustainable pumping hours, and assess aquifer recovery time. Supports metric and imperial units for global use.
Enter the results from your borewell drilling report or a field pump test to estimate actual water yield. If you don’t have a pump test, use the Drilling Log Method based on water-bearing zones encountered during drilling.
Compare your borewell’s water supply against your farm’s irrigation demand. Find out if your borewell is sufficient, how many hours to pump daily, and whether you need supplemental storage.
A recovery test measures how fast the water level rises after pumping stops. This helps estimate the aquifer recharge rate and safe sustainable yield — the amount you can pump without permanently depleting the aquifer.
Reference data for borewell planning, yield classification, and aquifer types.
Borewell Yield Classification
| Yield (LPH) | Yield (GPH) | Classification | Farm Suitability |
|---|---|---|---|
| < 500 | < 132 | Very Poor | Domestic use only |
| 500 – 2,000 | 132 – 528 | Poor | Small kitchen garden |
| 2,000 – 5,000 | 528 – 1,320 | Moderate | 0.5–1 acre drip irrigation |
| 5,000 – 10,000 | 1,320 – 2,642 | Good | 1–2 acres with drip |
| 10,000 – 20,000 | 2,642 – 5,283 | Very Good | 2–5 acres with drip |
| > 20,000 | > 5,283 | Excellent | 5+ acres, any system |
Typical Yield by Aquifer / Rock Type
| Rock / Aquifer Type | Typical Yield Range (LPH) | Depth Range | Notes |
|---|---|---|---|
| Hard Rock (Granite/Basalt) | 500 – 8,000 | 60–300 m | Yield depends on fractures. Variable. |
| Weathered / Saprolite Zone | 1,000 – 6,000 | 20–80 m | Often high yield but seasonal |
| Sand / Gravel Aquifer | 5,000 – 50,000+ | 10–100 m | Best yields. Consistent year-round. |
| Limestone / Karst | 2,000 – 30,000 | 30–200 m | High yield where cave systems exist |
| Alluvial / River Valley | 5,000 – 40,000 | 10–60 m | Excellent yields near rivers |
| Sandstone | 1,000 – 15,000 | 50–300 m | Good if well cemented |
| Shale / Clay | 200 – 2,000 | Varies | Poor yield, often poor quality |
Recovery Rate Classification
| Recovery in 60 min (%) | Classification | Recommended Rest Period |
|---|---|---|
| > 90% | Excellent Recharge | 1–2 hours |
| 70 – 90% | Good Recharge | 2–4 hours |
| 50 – 70% | Moderate Recharge | 4–6 hours |
| 30 – 50% | Slow Recharge | 6–12 hours |
| < 30% | Very Slow / Poor | 12–24 hours |
Standard Borewell Casing Sizes
| Use | Diameter (mm) | Diameter (inches) |
|---|---|---|
| Domestic / Small Farm | 100–115 mm | 4 – 4.5 inch |
| Medium Farm | 150 mm | 6 inch |
| Large Farm / Commercial | 200 mm | 8 inch |
| Municipal / Industrial | 250–300 mm | 10–12 inch |
What Is Borewell Yield and Why Does It Matter?
Borewell yield is the rate at which groundwater flows into a borewell from the surrounding aquifer — measured in liters per hour (LPH), liters per minute (LPM), or gallons per hour (GPH). It tells you how fast the borewell “refills” during and after pumping.
Yield is not the same as pump discharge. A pump can be set to deliver 10,000 LPH, but if the borewell yield is only 4,000 LPH, the pump will eventually run dry — drawing air, damaging the motor, and potentially dewatering the aquifer permanently.
Understanding your true borewell yield is critical for three reasons:
Pump Sizing: Installing a pump larger than your borewell yield is one of the most common and costly mistakes in rural water management. An oversized pump will drain the borewell faster than the aquifer can recharge it, leading to air-lock, motor burnout, and permanent yield reduction.
Irrigation Planning: Your daily water requirement depends on your crop type, field area, and irrigation method. Without knowing your borewell yield, you cannot plan a reliable irrigation schedule or decide how much land you can bring under cultivation.
Aquifer Sustainability: Groundwater is not an infinite resource. Every borewell has a sustainable yield — the maximum rate at which water can be extracted without permanently depleting the aquifer. Exceeding this limit year after year leads to falling water tables, reduced yields, and eventually complete borewell failure.
Three Methods to Estimate Borewell Yield — Explained
Our calculator supports three different estimation methods, each suited to a different level of data availability.
Method 1 — Pump Test Method (Most Accurate)
A pump test is the most reliable way to measure borewell yield. It involves pumping the borewell at a known rate for a fixed period and measuring the total volume of water discharged.
How to conduct a simple pump test:
Install a flow meter or use a calibrated container to measure water output. Run the pump continuously for at least 60 minutes — ideally 4–8 hours for a proper step-drawdown test. Record the total volume pumped and the exact duration. Also measure the static water level before pumping begins and the dynamic water level at the end of the test.
The formula is straightforward:
Yield (LPH) = Total Volume Pumped (Liters) ÷ Duration (Hours)
For example, if you pump 6,000 liters in 60 minutes, your yield is 6,000 LPH. The calculator does this conversion automatically regardless of whether you enter minutes, hours, liters, gallons, or cubic meters.
What a proper pump test also tells you:
Beyond the basic yield figure, a pump test reveals the drawdown — the distance the water level drops during pumping. A large drawdown relative to yield indicates low aquifer transmissivity, meaning the water table will drop significantly during sustained pumping. A small drawdown for the same yield indicates a highly transmissive aquifer that can sustain long pumping periods.
Method 2 — Specific Capacity / Drawdown Method
If you have a driller’s report that includes specific capacity data, this method gives a reliable yield estimate without needing a full pump test. Specific capacity is expressed as yield per unit of drawdown — typically in liters per hour per meter of drawdown (LPH/m).
The formula:
Yield (LPH) = Specific Capacity (LPH/m) × Available Drawdown (m)
Available drawdown is the distance between the static water level and the pump setting depth. The greater the available drawdown, the higher the potential yield.
This method is useful when you have historical pump test data from a nearby well in the same aquifer, or when your driller provides specific capacity figures from the drilling report.
Method 3 — Water Zone / Drilling Log Method
This method estimates yield from the drilling log — the record of what rock formations and water-bearing zones were encountered during drilling. Every time the drill bit crosses a water-bearing fracture, fissure, or permeable layer, the driller records its depth and notes the water strike intensity.
Our calculator uses the depth and thickness of each water-bearing zone combined with the rock type and strike intensity to estimate total yield. While less precise than a pump test, this method gives farmers a useful first estimate when no test data is available.
Water strike intensity guide:
- Weak seepage — small quantities slowly entering the borehole
- Moderate flow — steady water entry, borehole fills noticeably
- Strong flow — rapid water entry, visible in the borehole
- Very strong flow — high-pressure water entry, borehole fills quickly
The rock type also matters significantly. Sand and gravel aquifers typically yield 5 to 10 times more water than equivalent-depth hard rock borewells, and alluvial formations near rivers can yield 20,000–50,000 LPH even at shallow depths.
Understanding Static and Dynamic Water Levels
Two water level measurements are fundamental to borewell assessment — and every farmer who relies on a borewell should understand them.
Static Water Level (SWL): The depth to the water surface in a borewell that has not been pumped for at least 4–8 hours. This represents the natural groundwater table in your area. SWL typically rises during and after the monsoon season and drops during summer as groundwater is extracted and not replaced at the same rate.
Dynamic Water Level (DWL): The depth to the water surface while the pump is running. As water is pumped out faster than the aquifer can supply it, the water level drops below the static level. The difference between SWL and DWL is called the drawdown.
Drawdown is the key indicator of aquifer stress. A borewell with 3 meters of drawdown during normal pumping is under very low stress. A borewell with 50 meters of drawdown suggests a poorly yielding formation or an oversized pump, and warrants immediate attention.
Monitoring SWL regularly — ideally monthly — tells you whether your groundwater table is stable, rising (good aquifer recharge), or falling (over-extraction or drought). Falling SWL over multiple years is a clear warning sign that the aquifer is being over-exploited and corrective action is needed.
The Aquifer Recovery Test — Your Most Important Borewell Health Check
The recovery test is something most farmers never conduct — but it provides more useful information about long-term borewell sustainability than almost any other measurement.
After a pumping session, the water level in a borewell begins to recover toward the static level. How quickly it recovers tells you everything about the aquifer’s ability to sustain prolonged pumping.
How to conduct a recovery test:
After at least 2–4 hours of pumping, stop the pump and immediately record the water level. Then measure the water level again at 15 minutes, 30 minutes, 60 minutes, and 120 minutes after stopping. Record each reading carefully.
Enter these measurements into the Recovery Test tab of our calculator. It will compute:
- The percentage of drawdown recovered at each time interval
- The recovery rate in meters per minute
- The estimated time for full recovery to the static level
- The aquifer recharge classification (Excellent to Very Poor)
- The recommended rest period between pumping sessions
- The sustainable daily yield — the volume you can safely extract without exceeding the aquifer’s recharge rate
What good recovery looks like:
A borewell that recovers more than 70% of its drawdown within 60 minutes is considered to have good recharge characteristics. You can typically pump 2–3 sessions per day with short rest periods between them. A borewell that recovers less than 30% in 60 minutes indicates a poorly recharged aquifer — perhaps due to hard rock with limited fractures, declining regional water table, or drought conditions. For such borewells, using a large storage tank and pumping only during overnight recovery periods is strongly recommended.
Borewell Yield vs. Farm Irrigation Demand — The Critical Calculation
Knowing your borewell yield is only half the equation. The other half is knowing how much water your farm actually needs every day — and whether your borewell can supply it within a reasonable pumping window.
Daily irrigation demand depends on:
- The crop being grown and its growth stage
- The field area under cultivation
- The irrigation method used (drip, sprinkler, flood)
- The prevailing evapotranspiration rate (see our ET Calculator)
Typical daily water demand by crop and area (approximate):
| Crop | Water Need per Acre per Day | With Drip (90% eff.) |
|---|---|---|
| Tomato | 35,000–50,000 L | 32,000–45,000 L |
| Onion | 20,000–30,000 L | 18,000–27,000 L |
| Sugarcane | 40,000–60,000 L | 36,000–54,000 L |
| Cotton | 25,000–40,000 L | 23,000–36,000 L |
| Wheat | 20,000–35,000 L | 18,000–32,000 L |
| Banana | 35,000–55,000 L | 32,000–50,000 L |
Example calculation:
A farmer has 2 acres of tomatoes. Daily demand = approximately 70,000–100,000 liters. Borewell yield = 8,000 LPH. At 16 hours of pumping: 8,000 × 16 = 128,000 liters — sufficient.
But if borewell yield is only 3,000 LPH: 3,000 × 16 = 48,000 liters — insufficient for 2 acres. The farmer must either reduce cultivated area to about 1 acre or invest in a second borewell or farm pond.
The Demand vs Supply tab of our calculator performs this analysis automatically, accounting for pump efficiency, number of borewells, available pumping hours, and storage capacity.
Borewell Yield by Rock and Aquifer Type
One of the most important factors determining borewell yield is the geological formation in which it is drilled. Understanding your region’s geology helps set realistic yield expectations before drilling begins.
Hard Rock Aquifers (Granite, Basalt, Gneiss): These are the most common rock types across large parts of India (Deccan Plateau, Karnataka, Telangana), southern Africa, and parts of Brazil. Yield depends almost entirely on the presence and connectivity of fractures and joints in the rock. A borewell that strikes a major fracture zone may yield 8,000–15,000 LPH, while one drilled just 20 meters away through unfractured rock may yield only 200–500 LPH. Hard rock borewells in drought-prone areas often show dramatic seasonal yield fluctuations.
Weathered / Saprolite Zone: The upper weathered layer above hard rock often contains moderately permeable material that supports steady yields of 1,000–6,000 LPH. This zone is typically 20–60 meters deep and is recharged relatively quickly after rainfall. However, it can run dry in extended droughts.
Sand and Gravel Aquifers: Found in river valleys, alluvial plains, and coastal areas, these are the most productive aquifers. Yields of 20,000–100,000 LPH are common. Water levels are generally stable year-round in major river basin aquifers, though overextraction in irrigated areas has caused significant water table declines in some regions.
Limestone and Karst Aquifers: Where underground cave and conduit systems exist — common in parts of Europe, the Caribbean, Middle East, and Florida — yields can be extraordinary. However, water quality may vary, and karst aquifers can be vulnerable to contamination.
Alluvial and Sedimentary Formations: River floodplains and sedimentary basins typically have excellent yields due to high porosity sand and gravel layers. Wells in the Indo-Gangetic Plain of northern India, the Nile Delta, and the Mississippi Valley commonly yield 30,000–80,000 LPH.
How Many Acres Can a Borewell Irrigate?
This is one of the most frequently asked questions among farmers planning new cultivation. The answer depends on borewell yield, pumping hours, irrigation method efficiency, and crop water demand.
General guidelines (drip irrigation, moderate water-demand crops):
| Borewell Yield | Max Pumping Hours | Daily Volume | Approximate Irrigable Area |
|---|---|---|---|
| 2,000 LPH | 16 hrs | 32,000 L | 0.5–0.8 Acres |
| 5,000 LPH | 16 hrs | 80,000 L | 1.5–2 Acres |
| 8,000 LPH | 16 hrs | 128,000 L | 2–3 Acres |
| 12,000 LPH | 16 hrs | 192,000 L | 3–5 Acres |
| 20,000 LPH | 16 hrs | 320,000 L | 5–8 Acres |
These are approximate figures for crops with moderate water demand under drip irrigation. High water-demand crops like sugarcane and banana will require more water per acre, reducing the irrigable area. Low water-demand crops like onion and wheat will allow more area per unit yield.
Protecting Your Borewell and Aquifer for the Long Term
Over-pumping a borewell beyond its sustainable yield is like withdrawing more money from a bank account than is being deposited — eventually the account goes to zero. Sustainable groundwater management is not just good environmental practice; it is critical for the long-term viability of your farm.
Key practices for borewell longevity:
Never pump below the pump intake level. Running a submersible pump without water — called dry running — destroys the motor windings within minutes. Install a water level sensor and automatic cut-off to prevent dry running.
Install a proper pump sized for your yield. The pump’s rated discharge should not exceed the borewell yield by more than 10–15%. An oversized pump will always run the borewell dry.
Conduct the recovery test annually. Declining recovery rates over successive years indicate falling groundwater levels or aquifer depletion. Catching this early allows corrective action before the borewell fails completely.
Implement recharge measures. On-farm rainwater harvesting structures — check dams, percolation ponds, contour bunds, and infiltration trenches — help replenish the aquifer during monsoon season, sustaining yield through the dry months.
Use borewell water efficiently. Every liter of borewell water delivered through flood irrigation instead of drip irrigation wastes 30–40% more groundwater. Converting from flood to drip irrigation effectively increases your borewell’s capacity to irrigate 40–60% more area for the same pump running time.
Clean and redevelop the borewell periodically. Over time, bacterial biofilm, mineral deposits, and fine sediment can clog the perforations in the casing and reduce yield by 20–40%. Periodic surging, air-lifting, or acid treatment by a professional well service contractor can restore much of the original yield.
Borewell Drilling Tips for Farmers Planning a New Borewell
If you are planning to drill a new borewell, here is what to consider before the drilling rig arrives.
Choose the right location. Consult a hydrogeologist or conduct a geophysical survey (resistivity survey or seismic survey) to identify the most promising drilling location. Drilling based on traditional water-divining practices alone leads to failure rates of 30–50% in hard rock areas.
Check government records. In most countries, groundwater departments maintain drilling logs from nearby wells. These records tell you the expected geology, water-bearing zones, and yield at different depths in your area — valuable information before you commit to drilling costs.
Agree on a yield guarantee. Reputable drillers will conduct a preliminary pump test after drilling and before casing installation. Agree in advance what minimum yield constitutes a successful borewell and what the driller’s obligation is if yield falls below that threshold.
Drill to the right depth. Drilling deeper does not always mean more water. In hard rock areas, the most productive fractures are often within the first 150–200 meters. Beyond 250 meters, additional yield is uncertain and drilling costs escalate significantly.
Proper casing and screen selection. The casing diameter, material (PVC vs. HDPE vs. steel), and screen slot size must match the aquifer type. In sand aquifers, an undersized screen will restrict flow and reduce yield even from a highly productive formation.
Frequently Asked Questions (FAQ)
Q. How do I measure my borewell yield without a flow meter? Use the bucket and stopwatch method. Place a large calibrated container (such as a 200-liter drum) at the pump outlet. Measure how long it takes to fill the container completely. Divide the container volume by the time in minutes, then multiply by 60 to get LPH. For example, if a 200-liter drum fills in 2 minutes: 200 ÷ 2 × 60 = 6,000 LPH.
Q. My borewell was good last year but yield has dropped. What happened? Several factors can cause yield decline: seasonal water table drop (common in summer), neighboring borewells creating competing drawdown cones, borewell casing corrosion or screen clogging, regional aquifer depletion from over-extraction, or drought reducing aquifer recharge. Conduct a recovery test to determine if the aquifer is still rechargeable or if the issue is mechanical clogging.
Q. What is the difference between borewell yield and pump discharge? Borewell yield is the rate at which groundwater enters the borewell from the aquifer. Pump discharge is the rate at which the pump removes water from the borewell. If pump discharge exceeds borewell yield, the borewell will drain faster than it refills. For sustainable operation, pump discharge should match or be slightly below borewell yield.
Q. How deep should a borewell be? Optimal borewell depth depends on local geology and groundwater table depth. In hard rock areas of southern India, productive fractures are typically found between 60 and 200 meters. In alluvial plains, borewells of 30–80 meters often access highly productive sand aquifers. Your state or district groundwater department can provide guidance based on local drilling records.
Q. Can I increase my borewell yield? Yes, in some cases. Hydrofracturing (hydraulic fracturing) can improve yield in hard rock borewells by creating or enlarging fractures that connect to the main aquifer. Borewell redevelopment by air-lifting or surging can restore yield lost to clogging. However, if the aquifer itself has low transmissivity, there is a natural upper limit to yield that cannot be exceeded regardless of technique.
Q. What is a safe pumping rate to avoid aquifer damage? Never pump at a rate that causes the dynamic water level to drop below the pump intake. As a general rule, allow the water level to recover to at least 70% of the static level before the next pumping session. This means scheduling pump-off periods between sessions based on your measured recovery rate.
Q. How does rainfall affect borewell yield? Borewell yield is directly connected to aquifer recharge, which is primarily driven by rainfall and surface water infiltration. In most unconfined aquifers, yield is significantly higher during and immediately after the monsoon/rainy season. It typically declines through the dry season as stored groundwater is extracted. Multi-year droughts can cause persistent yield decline even after rainfall returns to normal.
Q. Do borewells need maintenance? Yes. Annual inspection of the pump, motor, rising main, and electrical connections is recommended. Every 3–5 years, a camera inspection of the borewell casing can identify corrosion, casing damage, or sediment buildup. Borewell redevelopment every 5–8 years in sandy or high-sediment aquifers can restore significant yield losses from screen clogging.
Conclusion
A borewell is one of the most significant investments a farmer makes — often costing thousands of dollars in drilling, casing, pump, and electrical installation. Yet the vast majority of borewell owners never properly measure their yield, never conduct a recovery test, and never calculate whether their borewell can actually support their irrigation plan.
The result is all too familiar: over-pumped borewells that fail mid-season, pumps that burn out from dry running, crops that wilt during critical growth stages, and farmers who borrowed money to drill a borewell that cannot support the crops they planted.
Our Borewell Yield Estimator gives every farmer the tools to avoid these outcomes. Use the Pump Test tab to measure your actual yield from field data. Use the Demand vs Supply tab to verify that your borewell can meet your irrigation requirement. Use the Recovery Test tab to understand your aquifer’s recharge rate and calculate a pumping schedule that keeps your borewell productive for decades, not just seasons.
Groundwater is one of agriculture’s most precious and most threatened resources. Using it wisely — guided by accurate measurement and smart scheduling — is both good farming practice and a responsibility to future generations of farmers who will depend on the same aquifer.
💧 Measure your yield. Know your limits. Farm sustainably.
Explore More Water Management Calculators:
- Drip Irrigation Layout Calculator — Pipe lengths, dripper count & discharge
- Water Tank / Farm Pond Capacity Calculator — Plan your storage needs
- Evapotranspiration (ET) Calculator — Calculate exact crop water demand
- Pump Power (HP) Calculator — Size the right pump for your borewell
- Rainwater Harvesting Calculator — Capture rooftop and field runoff
References: Central Ground Water Board (CGWB) India — Ground Water Year Book | FAO Irrigation and Drainage Paper No. 57 — Guidelines for Predicting Crop Water Requirements | Driscoll (1986) — Groundwater and Wells | USGS Groundwater Technical Procedures
This calculator is for planning and educational purposes only. For borewell siting, drilling design, and hydrogeological assessment, always engage a licensed hydrogeologist or groundwater professional.