How much landscape can you irrigate?
Use this formula to calculate the square footage of landscape to be irrigated:
LA= GW (ETxPFx0.62)
LA = Landscaped area
GW = Estimated Grey Water (gallons per week)
ET = Evapotranspiration (inches per week)*
PF = Plant Factor
0.62 = (inches of ET to gallons per week)
LA= 1120 ( 120gx7 days = 840 g. per wk) divided by 2x.8x.062
Landscaped area = 1120 square feet.
*Evapotranspiration is the amount of water lost through evaporation from the soil and transpiration from the plant. This varies depending on location.