What this tool does
Makes event volume and outlet count visible so one large laundry discharge is not confused with a smooth daily average.
When to use it
Use after measuring the washing machine's actual discharge and after defining a locally acceptable per-basin event range for the plants and soil.
Inputs and supported units
Each labelled field explains the quantity it expects. Unit-system changes convert existing numeric entries once and keep calculations on a single SI internal basis. Supported shared units include L/min and GPM, metres and feet, kPa and psi, millimetres and inches, kW and hp, and °C and °F as relevant.
Calculation or decision method
Minimum outlets = ceil(load / maximum target); maximum outlets = floor(load / minimum target)
How to interpret the result
Read the primary result with the supporting breakdown and warning. A plausible number is not evidence that every input, operating case or design constraint has been included.
Worked example
A 60 L load with a user-entered 10–20 L target per outlet has a feasible range of three to six outlets; four outlets receive 15 L each.
Assumptions
Entered fixture, event, climate, soil and tariff values describe the planning case; volumes are kept on an SI internal basis.
Limitations
The result is a preliminary quantity or cost screen. It does not approve a source, end use, plumbing connection, treatment process, setback, storage time or irrigation method.
Sources
- San Francisco Public Utilities Commission — Graywater Design Manual
- Washington State Department of Health — Greywater Reuse
- U.S. EPA WaterSense — Water Budget Tool
- Australian Government — Australian Guidelines for Water Recycling