💧 Irrigation Water Calculator
Calculate water volume, flow rate & run time for any irrigation area — imperial & metric
| Water Depth | Gallons per 1,000 sq ft | Liters per 100 m² | Acre-Inches |
|---|---|---|---|
| 0.25 in (6 mm) | 156 | 636 | 0.25 |
| 0.5 in (13 mm) | 312 | 1,272 | 0.50 |
| 0.75 in (19 mm) | 468 | 1,908 | 0.75 |
| 1.0 in (25 mm) | 623 | 2,540 | 1.00 |
| 1.5 in (38 mm) | 935 | 3,810 | 1.50 |
| 2.0 in (51 mm) | 1,246 | 5,080 | 2.00 |
| 3.0 in (76 mm) | 1,869 | 7,620 | 3.00 |
| 4.0 in (102 mm) | 2,492 | 10,160 | 4.00 |
| Flow Rate (GPM) | Gallons per Hour | L per Hour | Acres per Hour at 1" |
|---|---|---|---|
| 1 GPM | 60 | 227 | 0.002 |
| 2 GPM | 120 | 454 | 0.004 |
| 5 GPM | 300 | 1,136 | 0.011 |
| 10 GPM | 600 | 2,271 | 0.022 |
| 15 GPM | 900 | 3,407 | 0.033 |
| 20 GPM | 1,200 | 4,542 | 0.044 |
| 50 GPM | 3,000 | 11,356 | 0.110 |
| 100 GPM | 6,000 | 22,712 | 0.221 |
| Project | Area (sq ft) | Gallons Needed | Run Time at 10 GPM |
|---|---|---|---|
| Small Raised Bed | 80 | 50 | 5 min |
| Small Garden Bed | 200 | 125 | 12.5 min |
| Average Backyard | 600 | 374 | 37 min |
| Standard Lawn | 2,000 | 1,246 | 2.1 hrs |
| Large Lawn | 5,000 | 3,115 | 5.2 hrs |
| Half Acre Field | 21,780 | 13,577 | 22.6 hrs |
| 1 Acre Field | 43,560 | 27,154 | 45.3 hrs |
| 5 Acre Farm Zone | 217,800 | 135,770 | 226 hrs |
| From | To | Multiply By | Notes |
|---|---|---|---|
| Gallons | Liters | 3.785 | US gallon |
| Sq ft | Sq meters | 0.0929 | Area conversion |
| Cubic ft | Cubic meters | 0.0283 | Volume conversion |
| GPM | L/min | 3.785 | Flow rate |
| GPM | m³/hr | 0.2271 | Flow rate |
| Acres | Sq meters | 4046.9 | Land area |
| Inches (depth) | mm (depth) | 25.4 | Depth |
| Acre-inch | Gallons | 27,154 | Volume per acre |
Always divide your calculated gross water volume by your system's efficiency rating to get the actual water you need to apply. A drip system at 90% efficiency means you apply 10% more than the theoretical minimum.
Run Time (minutes) = Total Gallons ÷ Flow Rate (GPM). For example, if you need 600 gallons and your system flows at 10 GPM, run time = 60 minutes. Split into shorter cycles to reduce runoff and improve absorption.
Installing a sprinkler system for a home lawn can cost a few hundreds of dollars up to several thousands mainly according to the size of the yard and the mode of installation. For a typical home yard, the installation of lawn irrigation usually ranges between 1 800 and 5 200 dollars, where the most common expenses fall between 2 200 and 4 600 dollars according to the yard size and the complexity of the system.
The Irrigation cost for installing sprinkler lines ranges from 0,50 up to 2,50 dollars each square foot, or from 600 up to 2 000 dollars each zone, or fully from 3 000 up to 10 000 dollars for a standard quarter-acre lawn. A standard underground sprinkler system for a quarter-acre land costs from 1 679 up to 3 541 dollars, while above-ground systems for a full acre go from 1 800 up to 2 000 dollars. Adding a sprinkler monitor adds an extra 10 up to 325 dollars.
How Much Does a Home Lawn Sprinkler Cost?
Contractors usually count the work for sprinklers according to zones. Cost for one zone is 585 up to 1 335 dollars, and a standard big lawn requires at least seven zones. Extra zones cost around 750 dollars each to install.
The price can raech 700 up to 1 200 dollars each zone according to the region. For a lot of 6 600 square feet, an underground system with different zones for flower beds and lawn can cost around 7 000 up to 9 000 dollars.
Doing it yourself helps to save a lot. Home-made installations for a third of an acre reach around 1 700 dollars for ten zones, expert monitor, 40 heads and 1 200 feet of tubes. Hiring a professional four a sprinkler system on average costs 3 000 up to 4 000 dollars, even so home-made work could stay under 1 500 dollars.
For small areas of quarter-acre or less, one commonly does it for around 5 000 dollars, including a backflow prevention device.
Drip irrigation commonly is a cheaper option in many situations. It normally costs from 310 up to 815 dollars, with an average of 520 dollars. The price can drop to 55 dollars or rise to 2 850 dollars.
Drip lines cost 1,50 up to 4,50 dollars each square foot to install. Drip irrigation ranks between the most cost-effective ways to water and is simple to set up, so doing it yourself helps to avoid costs for labor. Home-made drip setups can cost from 30 up to 400 dollars.
Irrigation specialists usually charge 45 up to 100 dollars each hour, but rocky or dense soil can raise that. In some regions, simply calling a licensed plumber costs already around 300 dollars. The place plays a big role.
In areas with high living costs, some specialists charge more. Running the system adds extra ongoing expenses. Typical home uses consume around 30 000 gallons yearly for outdoor spraying, and an expert monitor canreduce that water amount.
