Indigenous plants for informal greywater treatment and reuse by some households in Ghana

Poor greywater management is one of Ghana's sanitation nightmares due to longstanding neglect. This study looks at local practices of informal phytoremediation, and identifies commonly used plants and benefits. Our study collected data from 451 surveyed houses in nine communities within three regions, using structured questionnaires and extensive field observations. Greywater (kitchen, bathroom and laundry) is mainly disposed of into the open (46–66%), with few (4–24%) using septic tanks and soakaway systems. The majority of respondents (84%) perceived plants as agents of treatment and most could list 1–2 beneficial functions of the plants. A total of 1,259 plant groups were identified which belonged to 36 different plant species. The top five indigenous plants used are sugarcane, banana/plantain, taro, sweet/wild basil, and dandelion. The major plant benefits identified were food (84% of respondents) and medicine (62% of respondents). Statistically, no association was identified between the numbers of plants grown and their perceived plant roles (χ2 = 6.022, p = 0.304), with the exception of an association between plant numbers and benefits (χ2 = 161.94, p < 0.001). There is demand for improving local practices of using plants in greywater treatment and reuse, since native plants also come with other benefits.