Water & environment · Calculator companion · By K Imports
Garden irrigation water: practical guide
This guide explains how to use the Count.ie garden irrigation water. Calculate supplemental water, hose run time and metered cost. Follow the inputs, method and worked example below, then compare your own scenario.
Guide written .
Open the Garden irrigation water calculatorWhat to prepare
- Record the relevant area, volume, mass, rainfall or usage measurement.
- Identify the source and period of any entered factor.
- State the assessment boundary: what activity is included and what is outside the model.
Understand the inputs
The calculation method
Net depth = max(0, target − effective rainfall). Litres = area × net depth ÷ efficiency; time = litres ÷ flow.
Worked example
Illustrative inputs and their result.
Example inputs
- Garden area (m²)
- 100
- Target watering depth (mm)
- 20
- Effective recent rainfall (mm)
- 5
- Application efficiency (%)
- 80
- Measured flow (litres/minute)
- 12
- Applicable metered water price (€/m³)
- 0
Calculated example result
- Applied Litres
- 1,875 L
- Watering Minutes
- 156.25 min
How to interpret the result
An entered-factor estimate is not an audited footprint or certification. Results depend on the selected boundary, factor, units and local conditions.
Use the same boundary and factor source for each scenario. Report assumptions alongside savings or changes so the comparison can be reproduced.
Common mistakes to avoid
- Do not present an assumed factor as a measured local result.
- Avoid counting an activity in two categories of the same assessment.
- Distinguish potential collection or diversion from the quantity actually achieved.
Assumptions and sources
Target depth depends on plants, soil and weather. Price is optional and not a statement that ordinary Irish domestic water is charged; restrictions and runoff are excluded.
If your case falls outside this scope, use a more suitable calculator or contact us about an unclear method.