Practical reference pages for irrigation designers, pump and irrigation retailers, and water professionals. Each worked example shows its units, assumptions and the checks still required.
Guides & worked examples
Choose a calculation to work through
Follow the inputs, equations and assumptions before working on a project design.
Actual calculation examples
Sample irrigation calculation reports
Four PDF examples with pump curves, pipe pressure loss, Hunter solenoid cable sizing and Amiad filtration. Inputs and limitations included.
View sample reportsSoftware selection
Choosing irrigation design software
Compare calculations, CAD needs, reports, units and trial availability against the work you need to deliver.
Read the selection guideDesign guide
Centre pivot design: area, flow and operating time
Work through a 300 m radius example, allocate flow by irrigated area and connect the duty to the sprinkler and pump design.
Read the worked examplePump sizing and selection calculators
How to size an irrigation pump
Build a duty point from the operating zone, elevation, pressure and losses before comparing pump curves.
Read the worked examplePipe sizing and friction loss calculators
Irrigation pipe sizing and friction loss
Compare true internal bores, calculate velocity and account for both pipe and fitting losses.
Read the worked exampleField and crop irrigation calculators
Drip irrigation design: demand, flow and run time
Translate a crop water requirement into daily volume and run time, then identify the lateral pressure checks.
Read the worked exampleWater treatment
Interpret the test, select the process, size the stage
These guides separate water-quality interpretation from process and equipment sizing.
Bore water
Bore water filtration and treatment
Move from laboratory evidence and design flow to a preliminary treatment sequence and the correct sizing calculation.
Read the bore-water guideWater analysis
Interpret a water laboratory report
Review mixed units, reporting limits, missing tests and a worked bore-water example.
Process selection
Choose preliminary treatment stages
Map water-quality findings to softening, iron removal, membranes, filtration and disinfection checks.
Hardness
Size a water softener
Compare domestic and industrial resin, vessel, salt and regeneration calculations.
Iron and manganese
Size an iron-removal filter
Use the measured Fe, Mn and H2S results to assess a DMI-65 duty.
Membranes
Design a preliminary RO skid
Review a brackish-water membrane array, mass balance and verification steps.
Membranes
Size an ultrafiltration system
Calculate modules, racks, recovery, backwash and air-scour requirements.
Worked examples across water engineering
Choose the question you need to answer. Each example states its inputs and shows where a project-specific design check is still needed.
| Task | What the example explains |
|---|---|
| Irrigation depth and run time | Net depth, gross volume and operating hours. |
| Dam volume and water storage | Top, middle and bottom areas in a 6 ML dam. |
| Dosing-pump flow | Water flow and active dose to stock-solution delivery. |
| Pump energy and payback | Annual operating costs and a complete simple-payback case. |
| Wastewater load and storage | BOD mass loading and available emergency storage time. |
| Pool volume and turnover | Water volume and an assumed circulation period. |
| Ventilation airflow | Room volume, air changes and the limits of that calculation. |
| Flow and pressure units | Metric conversions, head and gallon definitions. |
| Solar-pumping water reserve | Daily demand and usable reserve storage. |
| Feed conversion ratio | Feed and biomass gain on a consistent stock basis. |
Downloadable worksheet
Prepare a centre-pivot design brief
Collect the site, water demand, machine, sprinkler and supply-main inputs in a two-page fillable PDF. Record missing evidence and the person who will check it.
Download the centre-pivot design brief (PDF, 2 pages) · Compare operating hours and flow · Read the supply-main report
How to use these guides
Read the assumptions before using an equation. Follow the links between crop demand, pipe losses and pump duty to see how one decision affects the next. The numerical cases are static educational examples; they do not run the subscription calculators.
Methods, limitations and corrections · Explore all calculator categories