Greywater Recycling System — FarmPal

Reuse water from sinks, showers, and laundry for garden irrigation. A simple greywater system can reduce freshwater demand by 30-50%, keeping valuable water and nutrients in your garden instead of the septic system.

How It Works

Drain water from sinks, showers, and washing machines is diverted before reaching the septic system. This water flows through a simple mulch basin or branched drain system directly to fruit trees, garden beds, and landscape plants.

Site Requirements

  • •Plumbing access to separate grey from black water
  • •Downslope garden or landscape area (gravity flow)
  • •Mulch basin or distribution area at least 10 feet from house
  • •Soil that drains (not waterlogged clay)
  • •Plants that benefit from regular water

Components

Diverter Valve
Switch between greywater and septic when needed
$20-100
Surge Tank (optional)
Buffer flow surges and settle particles
$10-50
Distribution Pipe
Carry water to garden areas
$20-100
Mulch Basins
Receive and filter water around plants
$0-50

Sizing Guide

Average household produces 30-50 gallons of greywater per person per day

Formula
Shower: 15-25 gal | Laundry: 15-40 gal/load | Sink: 5-10 gal/day
DIY Minimum
$25 (laundry to landscape with basic diverter)
DIY Typical
$100-500 (branched drain to fruit trees)
Professional
$1,000-5,000 (whole-house system)
Annual Maint.
$0-50 (refresh mulch basins annually)

DIY Steps

1
Laundry-to-Landscape (Start Here)

The simplest legal greywater system in most areas. Washing machine pump pushes water outside through a 1" pipe to mulch basins around fruit trees.

⏱ 2-4 hours
2
Branched Drain System

Gravity-fed system from showers and bathroom sinks using 1.5" drain pipe split into multiple branches, each feeding a mulch basin.

⏱ 1-2 days
3
Constructed Wetland (Advanced)

For whole-house greywater treatment: a lined, gravel-filled wetland planted with reeds and water-loving plants that naturally filter and clean greywater.

⏱ 3-7 days

✓ Pros

  • •Reduces freshwater demand 30-50%
  • •Nutrients in greywater feed plants (phosphorus, nitrogen)
  • •Reduces septic system load (extends septic life)
  • •Simple systems are extremely cheap and easy
  • •Fruit trees love the consistent moisture

⚠️ Safety

  • •Never use greywater on root vegetables or leafy greens (pathogens)
  • •Greywater must infiltrate into soil never spray or let pool on surface
  • •Do not store greywater more than 24 hours (bacterial growth)
  • •Do not use if anyone in household has infectious illness