Managing wastewater agriculture to improve livelihoods and environmental quality in poor countries

Abstract

Deteriorating surface water quality from poor sewage disposal, and lack of alternative water sources have resulted in partially diluted and sometimes untreated wastewater being used for local irrigation in urban, peri-urban and even rural agriculture by the poor. Un(der)employment, and a demand for fresh perishable food products by city dwellers are other drivers of this practice.Scenarios typical of conditions in poor countries are presented through case studies focusing more specifically on India, Pakistan, Vietnam, and Ghana. These emphasize water and nutrient value and the necessity for conjunctive use. Year round availability that allows for multiple cultivation cycles results in a different cropping pattern to regular water use. Earnings from wastewater agriculture lift farmers out of poverty. Farming also ensures food security for the poorer households. Countering these benefits are health risks to farmers and consumers from helminth infections in particular. The current situation of wastewater agriculture requires immediate solutions.The policy implications of applying wastewater use guidelines in resource-poor situations are analyzed and short-term alternative management responses are presented. In conclusion the potential for land application of wastewater as a possible lower-cost solution which will simultaneously improve environmental sanitation and downstream water quality is briefly discussed. Copyright # 2005 John Wiley & Sons, Ltd.key words: wastewater agriculture; livelihoods; urban wastewater; water quality; health; city food supply RÉ SUMÉ La pollution des eaux de surface, due à une mauvaise gestion des eaux usées en milieu urbain, et la manque des sources alternatives en eau d'irrigation, ont poussé les pauvres d'utiliser des eaux polluées pour l'agriculture en zones urbaines et peri-urbaines, et rurales même. D'autres raisons pour ceci, sont le manque d'emplois et la demande croissante des villes pour des produits frais et périssable. L'article présente les manières qu'ils utilisent cette eau en pays pauvre, en étalant plus particulièrement des exemples venant de l'Inde, du Pakistan, du Vietnam et du Ghana. Ces exemples montrent l'importance attribuée à la valeur des nutriments contenus dans l'eau, et le besoin d'une utilisation conjonctive avec d'autres sources d'eau. La présence en continue de cette ressource a l'avantage de donner lieu à de multiples cycles de cultures maraîchers qui sont différents des cultures aux eaux propres. Les revenues aident à surmonter la pauvreté, et contribuent à l'approvisionnement en besoins alimentaires des cultivateurs. En contrepartie il y a les risques sanitaires surtout à travers les oeufs d'helminthes. La situation actuelle nécessite des solutions immédiates. La difficulté d'une application immédiate des normes OMS et les implications politiques sont présentées. La possibilité de mieux gérer l'agriculture à l'eau usée pour améliorer les conditions sanitaires dans les villes est relevée.

The challenges of wastewater irrigation in developing countries

“…Tunisia launched a national water reuse program in the early 1980s to increase usable water The foremost challenge for public agencies in developing countries is to determine the appropriate scale at which treatment is possible and viable with a particular emphasis on the separation of industrial and domestic wastewater to facilitate the likelihood of safe reuse (Huibers and Van Lier, 2005;Martijn and Redwood, 2005;Raschid-Sally et al, 2005). The optimal treatment strategy will vary with the economic and institutional capacities, wastewater sources and constituents, and should preferably consider the requirements of reuse than standards which are difficult to maintain (Emongor and Ramolemana, 2004;Fine et al, 2006;Tidåker et al, 2006).…”

Microbiological assessment of river water used for the irrigation of fresh produce in a sub-urban community in Sobantu, South Africa

“…Consequently, developing countries are becoming increasingly reliant on the use of wastewater for irrigation (Amoah, Drechsel, & Abaidoo, 2005;De Bon et al, 2010;Huibers & van Lier, 2005;Seidu et al, 2008). Although the use of wastewater can be beneficial by providing nutrients for crops thereby saving fertilizer costs (De Bon et al, 2010;Raschid-Sally, Carr, & Buechler, 2005;Van der Hoek et al, 2002), the potential health risks associated with its use need to be considered (Hamilton et al, 2007;Huibers & van Lier, 2005;Mara et al, 2007;Seidu et al, 2008;Shuval et al, 1986;Toze, 2006).…”

Cost–benefit and water resources policy: a survey

“…Better agricultural water management could contribute to poverty reduction along several pathways. First, access to rehable water raises productivity, improves job opportunities and stabilizes income (Raschid-Sally et al, 2005). Second, it encourages the use of non-water crop yield-enhancing resources and allows diversification into higher-income products, raises off-farm outputs and meets numerous household needs.…”