Abstract:
Greywater reuse has potential for non-potable applications that conserve freshwater resources in
water-stressed areas especially in sub-Saharan Africa. The feasibility of reusing greywater for
domestic activities in a rural area of Malawi, Africa, was evaluated from microbiological and public
acceptance perspectives. Median Escherichia coli concentrations for eight domestic greywater
sources (handwashing, laundry, runoff from a tap apron, bathing, cleaning a home/kitchen, cleaning
a water collection container, washing plates and soaking vegetables) ranged from 100 to >20,000
colony forming units (cfu)/100 ml. Twenty-four of 47 greywater samples tested (51%) met the World
Health Organization guideline for unrestricted use of greywater for irrigation. Pertinently, 80% (4/5)
and 60% (3/5) of greywater samples from handwashing stations and bathing had E. coli less than the
WHO guideline. Users reported greatest acceptance of reusing greywater for growing food and
washing clothes, especially when the greywater source was bathing. Acceptance was closely tied to
a household’s economic standing, geographic location, and first-hand knowledge of reusing
greywater. Greywater reuse practices in rural areas, especially targeting bathing water as suitable
from bacteriological and user perception criteria, can help mitigate the impacts of water stress in
sub-Saharan Africa.