Non-potable water requirement
Water requirement in litre per person and day: a. Drinking; b. Cooking; c. Dishwasher; d. Washing; e. Teeth brushing; f. Bathing - two times a week; g. Showering - two times a week; h. Toilet; i. Washing machine; j. House cleaning; k. Car washing; l. Flower watering; m. Garden irrigation
Source <ref name="Uni OL">DIN 1989-1</ref>