Wastewater Use In Agriculture Research Articles

Institutional and policy analysis of wastewater (re)use for agriculture: case study Hyderabad, India.

Wastewater constitutes an alternative water source for the irrigation sector. To fully benefit from it, and reduce possible adverse effects on public health and the environment, we need to look at the regulation of the practice. A prerequisite for this is an institutional analysis, and the points to consider are the institutional mandates. We used the city of Hyderabad, India, as a case study. There, irrigation with wastewater is not supported or recognized, but it happens in practice. It takes place in an indirect and unplanned way. Institutions fail at enforcing regulations, and little attention is given to formalization of the practice. With this article, we aim to untangle the institutional setup, and by doing so, identify the constraints surrounding development of a formal practice. Ultimately, we aim at contributing to the discussion on the agricultural use of wastewater.

Integrated Approach to Wastewater Use in Agriculture: A Pilot Study in Rajshahi City Corporation Area

Demand for water is increasing in the world parallel to increase in population and industrialization. In many developing countries, wastewater is the only source of water for irrigation during dry periods. Besides, wastewater is high in nutrient content which reduces the use of chemical fertilizers for crop cultivation. After a certain period, it will be unable to irrigate with ground water because of its limited quantities and contamination. To overcome this difficulties waste water may be a suitable source to meet the irrigation demand if properly managed and utilized in convenient way. In this study, wastewater samples were collected from four places of Rajshahi City Corporation (RCC) for determining water quality parameters. Analysis of these impurities were performed with strict quality control and quality assurance using the internationally accepted analytical chemical methods for the determination of their harmful effects on crops and found that most of the parameters exceed the permissible limits. The major problem in using wastewater in agriculture in the project area is the high level of faecal contamination. Thus, efforts are geared toward finding ways of utilizing the previously unused sources of water and/or recycling wastewater.DOI: http://dx.doi.org/10.3329/jesnr.v6i1.22061 J. Environ. Sci. & Natural Resources, 6(1): 167-171 2013

Diarrhoeal diseases among adult population in an agricultural community Hanam province, Vietnam, with high wastewater and excreta re-use.

BackgroundDespite the potential health risks of wastewater and excreta use as fertiliser in agriculture, it is still widespread in Vietnam. However, the importance of diarrheal risk in adults’ associated with the combined exposures to both excreta and wastewater use in agriculture is largely unknown. This study was carried out to determine diarrhoeal incidence and associated risk factors among the adult population exposed to wastewater and excreta used in agriculture in Hanam province, Vietnam.MethodsAn open cohort of 867 adults, aged 16–65 years, was followed weekly for 12 months to determine the incidence of diarrhoea. A nested case–control study was used to assess the risk factors of diarrhoeal episodes. Two hundred and thirty-two pairs of cases and controls were identified and exposure information related to wastewater, human and animal excreta, personal hygiene practices, and food and water consumption was collected.ResultsThe incidence rate of reported diarrhoea was 0.28 episodes per person-years at risk. The risk factors for diarrhoeal diseases included direct contact with the Nhue River water (odds ratio [OR] = 2.4, attributable fraction [AF] 27%), local pond water (OR = 2.3, AF 14%), composting of human excreta for a duration less than 3 months (OR = 2.4, AF 51%), handling human excreta in field work (OR = 5.4, AF 7%), handling animal excreta in field work (OR = 3.3, AF 36%), lack of protective measures while working (OR = 6.9, AF 78%), never or rarely washing hands with soap (OR = 3.3, AF 51%), use of rainwater for drinking (OR = 5.4, AF 77%) and eating raw vegetables the day before (OR = 2.4, AF 12%).ConclusionsOur study shows that professional exposure to wastewater and excreta during agricultural activities are significantly contributing to the risk of diarrhoea in adults. The highest attributable fractions were obtained for direct contact with Nhue River and local ponds, handling practices of human and animal excreta as fertilisers, lack of protective measures while working and poor personal hygiene practices, and unsafe food and water consumption were associated with the risk of diarrhoeal episodes in adults. Improve personal hygiene practices and use of relevant treated wastewater and excreta as the public health measures to reduce these exposures will be most effective and are urgently warranted.

Irrigação por gotejamento com água residuária tratada da indústria da castanha de caju sob pressões de serviço

The agricultural use of wastewater generated in the processing of cashew nuts enables the rationalization of water use, as well as the minimization of pollution and environmental degradation. The study aimed to analyze the effect of service pressures in the distribution uniformity of drip irrigation units applying treated wastewater from cashew nut industry. The experiment was conducted in split-split plots scheme having the service pressures (70, 140, 210 and 280 kPa) on parcels, the emitters models (G1, G2 and G3) on subplots and the evaluation periods (0, 20, 40, 60, 80, 100, 120, 140 and 160 h of operation of the irrigation units) on subsubplots. The treatments were distributed in a completely randomized design with three replications. The coefficient of uniformity of distribution of irrigation units, as well as the physical, chemical and microbiological characteristics of the effluent were determined every 20 hours of operation the irrigation units to totalize 160 h. The combination of dripper G3 and service pressure of 140 kPa provided excellent levels of distribution uniformity of effluent on irrigation units operating with treated wastewater of cashew nut industry. For application of treated wastewater from cashew nut it is not recommended the use of drippers with low flow rate (? 1.6 L h-1) and labyrinth of greater length (? 58 mm).

Wastewater use in agriculture in Sri Lanka A case study from Kurunegala Sri Lanka

Wastewater management, including treatment, is vital to protect human health and prevent thecontamination of lakes and rivers: but for most developing countries this solution is prohibitivelyexpensive. In such cases, applying wastewater to agricultural lands is a more economical alternativeand more ecologically sound than uncontrolled dumping of municipal effluents into lakes and streams,as it offers a form ofland based treatment. In rural and peri-urban areas of many developing countries,the use of sewage and wastewater for irrigation is common practice. This is often due to waterscarcity but even in areas where other water sources exist, small farmers may choose wastewaterbecause of its high nutrient content, which reduces the need for expensive chemical fertilizers. Theuse of wastewater in agriculture is thus a form of nutrient and water recycl ing; and this often reducesdownstream environmental impacts on soil and water resources. The outcome of this is improvedlivelihoods, food security and nutrition for many urban low income households. Despite these benefitsuncontrolled use of wastewater may be associated with significant negative human health impactsdue to the pathogens contained in the wastewater. Sri Lanka is no exception to this situation and yetwastewater agriculture in Sri Lanka is much less studied than in other countries and is happeningunnoticed at present. The objective of this paper is to explore the wastewater use in agriculture in thecity of Kurunegala and to suggest the way forward to better wastewater management and reuse.

Changes in chemical attributes of a Fluvent cultivated with castor bean and irrigated with wastewater

Agricultural use of wastewater is an alternative to increase water availability, especially in semiarid regions. However, it may cause undesirable chemical changes in the soil. The aim of this study was to evaluate the influence of wastewater irrigation and castor bean (Ricinus communis L.) cultivation on the chemical attributes of a Fluvic Neosol. The experimental design was in a randomized block, in split-plot scheme, where the main plots were represented by the treatments of irrigation water and castor bean cultivation, and the subplots were the soil layers, with three replications. The treatments were T1 - wastewater irrigation + castor bean cultivation ; T2 - mixture of supply water and wastewater (1:1 ratio) + castor bean cultivation; T3 - supply water irrigation + castor bean cultivation ; and T4 - wastewater application, without castor bean cultivation. The depths of soil layers were 0-10, 10-20, 20-30, 30-40, and 40-50 cm. At the end of study, the content of phosphorus, calcium, potassium, and organic matter increased mainly in the upper layers, and sodium increased in the deeper layers in the wastewater treatments, in comparison to the supply water irrigation. In T4, the disposal of wastewater increased the concentration of magnesium. The pH values, iron and zinc concentration did not statistically differ in the treatments.

Urban wastewater irrigation and its effect on growth, photosynthesis and yield of chickpea under different doses of potassium

The deficiency of potassium (K) has resulted in decreasing the yield and quality of food grains. Moreover, with decreasing water resources the use of wastewater in agriculture as an alternative source of water and nutrients is being debated. This study was therefore undertaken to test wastewater for its suitability as irrigation water together with uniform basal doses of nitrogen (N) and phosphorus (P) and varying doses of potassium (K0, K20, K40 and K60). It was observed that the plants receiving wastewater as a source of irrigation water performed better with a lower K dose. Potassium at 20 kg ha−1 along with wastewater resulted in better growth, photosynthetic rate (P N), stomatal conductance (g s) and yield of the chickpea (Cicer arietinum L.). Thus fertilizer rates could be lowered with the use of wastewater which can serve not only as the source of water but of nutrients also. However, regular monitoring of wastewater and soil for any buildup of heavy metal is necessary. The physical and chemical parameters of wastewater were also tested and most of them were found to be well within the permissible limits as set by the Food and Agriculture Organization (FAO).

Risk assessment of treated municipal wastewater reuse in Sicily

In Italy, the restrictive approach for treated wastewater reuse in agriculture has led to some difficulties in promoting this practice. In order to assess the health risk associated with the use of wastewater in agriculture, an experiment was conducted in an open field near the constructed wetland (CW) system of San Michele di Ganzaria (Eastern Sicily), during the irrigation seasons 2004-2009. In particular the impact on tomato crops of drip and sub-drip irrigation with treated municipal wastewater, as well as effects of wastewater reuse on the irrigation system, main production features, hydrological soil behaviour, and microbial soil and products contamination were investigated. Notwithstanding the fact that globally CW effluents did not match microbiological standards for wastewater reuse of Italian legislation, the median infection risk (function of the recommended tolerable additional disease burden of 10(-6) DALY (disability-adjusted life year) loss per person per year) suggested by the 2006 World Health Organization Guidelines for rotavirus, Campylobacter and Cryptosporidium for lettuce irrigation under unrestricted irrigation scenario was achieved.

Crescimento de mudas de cajueiro anão precoce irrigado com efluente doméstico tratado

The use of wastewater in agriculture can be considered an important alternative in the preservation of natural resources. With this objective an experiment was installed and conducted for the use wastewater of domestic origin in the growth phase of dwarf cashew seedlings clone CCP76. The experimental design was in a completely randomized block design with five treatments and five replicates. The treatments employed were as follows: T1 (100% residual water - AR), T2 (75% AR + 25% water supply - AA), T3 (50% AR + 50% AA), T4 (25% AR + 75% AA) and T5 (100% AA). There were four evaluation at every 10 days after germination (DAG) and the following parameters were evaluated: stem diameter, leaf number, leaf area, shoot and root length, fresh and dry weight of shoot and root system. The variables were not adversely affected by the use of wastewater except for dry weight of root and leaf area during the study period, and may be an alternative for the cultivation of cashew seedlings Clone CCP76.

The physiological and nutritional responses to an excess of boron by Verna lemon trees that were grafted on four contrasting rootstocks

Citrus species are sensitive to an excess of boron (B). Currently, this toxicity is becoming a serious problem in the soils of arid and semi-arid environments throughout the world, where high concentrations of B may occur due to the agricultural use of wastewater. Citrus rootstocks can greatly influence the tolerance of citrus trees to different abiotic stresses. However, little is known about how the rootstock influences the tolerance of these trees to an excess of B. In this study, the effects of the nutrient solution’s B concentration (0.25, 2, 4.5 or 7 mg l−1) on the growth and other physiological, nutritional and biochemical parameters of Verna lemon trees that were grafted on four contrasting rootstocks [Carrizo citrange (CC), Cleopatra mandarin (CL), Citrus macrophylla (CM) and sour orange (SO)] were investigated. The plants were grown in a greenhouse in pots containing a universal substrate media and were watered daily with a Hoagland nutrient solution containing different concentrations of B. The results showed that the plant growth was progressively inhibited with an increasing concentration of B in the nutrient solution. However, the shoot was more sensitive to the B toxicity than were the roots. In addition, the growth inhibition was reduced in trees that were grafted on CL and CM when compared with those that were grafted on CC and SO. The concentration of B in the leaves, stems and roots also increased with an increase in the concentration of external B in the following order: leaves > roots > stem. The rootstock also had an influence on the B concentration in the different plant tissues. In the leaves, the B concentration was lowest in the plants that were grafted on the SO rootstock followed by the plants that were grafted on either the CM or CL rootstock and highest in the plants that were grafted on the CC rootstock. The net assimilation of CO2 ( $$ A_{{{\text{CO}}_{2} }} $$ ) and the stomatal conductance (g s) leaf gas exchange parameters were reduced with an excess of B in the leaves, and this reduction was less pronounced for trees on CM and CL. The intercellular CO2 concentration (C i) and the chlorophyll fluorescence indicated that the reduction of $$ A_{{{\text{CO}}_{2} }} $$ that was found with an excess of B was mainly due to non-stomatal factors. The mineral nutrition and organic solute data are also shown in this study. All of the data indicate that the tolerance to an excess of B is not related to the concentration of B that has accumulated in the leaves, which indicates that a combination of rootstock-dependent physiological, biochemical and anatomical responses determine the tolerance to an excess of B in citrus plants.

Towards an agenda for improving wastewater use in agriculture

This paper sets out the trends and challenges of wastewater use in agriculture; identifies the risks and benefits of wastewater irrigation; describes the risk-assessment and management framework adopted by the World Health Organization, the Food and Agriculture Organization of the United Nations and other international and national organizations; and proposes measures for applying the framework to reduce health risks by moving from unplanned to a planned, integrated, approach to wastewater use for irrigation.

Motivating behaviour change to reduce pathogenic risk where unsafe water is used for irrigation

The increased emphasis on non- or post-treatment measures in the 2006 edition of the World Health Organization Guidelines on the safe use of wastewater in agriculture will require behaviour change along the food chain. Low health risk awareness likely limits adoption of safe food practices in many areas. Based on experiences from Ghana, where informal wastewater irrigation occurs around all cities, the necessary steps for increasing adoption probability are outlined under a generic framework, which is based on the four pillars of social marketing, incentive systems, awareness creation/education and application of regulations. Any of these approaches requires research of the target groups. Cost effectiveness can be improved by linking related efforts with other hygiene and food safety interventions.

Study on the impact of wastewater irrigation on the quality of oils obtained from olives harvested by hand and from the ground and extracted at different times after the harvesting

Nowadays, lots of efforts are made in Tunisia for the exploitation of wastewater in agriculture in order to face a very elevated mobilization of resources in water (90%). At Sfax, a Governorate placed in the South of Tunisia, the annual rainfall rarely exceeds 200 mm, so the climate is fairly arid. The significant water deficit can be reduced with the reuse of treated wastewater (TWW). The Sfax wastewater originated from the municipal wastewater treatment plant (WWTP) localized at 5 km in the south of Sfax, Tunisia. This WWTP is an aerated lagoon process receiving industrial wastewaters. Its treatment capacity is 24,000 m 3/day. Part of TWW is sent to the olive crops of El Hajeb, as part of a proposed wastewater use in agriculture. Already the wastewater is used to irrigate olive trees and intercrops such as cotton, oats and sorghum silage ( Charfi et al., 1999). The aim of the present work was to determine the impact of the irrigation utilizing wastewater on the quality of the oil. The oils analysed were extracted from olives hand-picked directly from the tree and from olives that have fallen under the trees. Moreover, a study on the olive storage has been made in order to evaluate in which way the collection of the fruit could influence the quality of the oil. The results obtained showed that: – Olive trees benefit from this contribution of water; – irrigation by wastewater has a significant effect in the fatty acid composition; – oils relative to olive trees irrigated with wastewaters are more sensible to the oxidization especially after olive storage; – oils coming from olive trees irrigated with wastewaters are richer in polyphenols; – oils extracted from fallen olives are of poor quality essentially after olives storage and when olive trees are irrigated by wastewater.

Water- and wastewater-related disease and infection risks: what is an appropriate value for the maximum tolerable additional burden of disease?

The maximum additional burden of water- and wastewater-related disease of 10-6 disability-adjusted life year (DALY) loss per person per year (pppy), used in the WHO Drinking-water Quality Guidelines and the WHO Guidelines for Wastewater Use in Agriculture, is based on US EPA'S acceptance of a 70-year lifetime waterborne cancer risk of 10(-5) per person, equivalent to an annual risk of 1.4x10(-7) per person which is four orders of magnitude lower than the actual all-cancer incidence in the USA in 2009 of 1.8x10(-3) pppy. A maximum additional burden of 10(-4) DALY loss pppy would reduce this risk to a more cost-effective, but still low, risk of 1.4x10(-5) pppy. It would increase the DALY loss pppy in low- and middle-income countries due to diarrhoeal diseases from the current level of 0.0119 pppy to 0.0120 pppy, and that due to ascariasis from 0.0026 pppy to 0.0027 pppy, but neither increase is of public-health significance. It is therefore recommended that the maximum additional burden of disease from these activities be increased to a DALY loss of 10(-4) pppy as this provides an adequate margin of public-health safety in relation to waterborne-cancer deaths, diarrhoeal disease and ascariasis in all countries.

Institutional aspects of integrating irrigation into urban wastewater management: the case of Hanoi, Vietnam

AbstractWastewater flows of metropolitan cities and their downstream use for irrigation are often associated with technical systems. However, an engineering approach on its own will leave questions unanswered at the socio‐technical and institutional level. Research was carried out in Hanoi, Vietnam, on the use of polluted irrigation water in periurban agriculture. Apart from outlining the physical features of the urban wastewater chain, a supply chain approach has been applied. Stakeholders along the management chain of the conventional urban wastewater system resemble “spot markets” (independent actors who act in self‐interest) as described in supply chain management literature. In Hanoi, the conventional approach towards wastewater management consists of a strict separation of urban wastewater management from periurban agricultural use and a neglect of farmers as stakeholders in the chain. It is suggested that the use of wastewater in agriculture should be incorporated into urban water management systems and that farmers should be included as acting stakeholders in the management of the wastewater chain. This paper concludes with suggestions for urban water management that are necessary to combine urban wastewater management with periurban agriculture. Copyright © 2008 John Wiley & Sons, Ltd.

Improving management of urban wastewater use in agriculture, Rajshahi, Bangladesh

Untreated wastewater is used informally for irrigation in many developing countries. This use needs to be managed to reduce the risks while maintaining its benefits. This paper documents the experience and lessons from a project in Rajshahi, Bangladesh, that aimed to do this. In line with the ‘multi-barrier approach’ advocated by the World Health Organization, a learning alliance approach was adopted whereby local stakeholders were brought together to analyse the issues, and implement a participatory action plan to deal effectively with the wastewater problem. The process resulted in negotiation between parties that rarely communicated previously and led to demand-driven actions including engineering solutions, policy review and community awareness programmes. While it built capacity and resulted in integrated solutions, it was resource intensive, and as the work is recent its sustainability is yet to be reviewed. This approach could facilitate stakeholders to effectively tackle wastewater reuse if certai...

Multi‐Criteria Decision Analysis of Treated Wastewater Use for Agriculture in Water Deficit Regions1

Al‐Juaidi, Ahmed E., Jagath J. Kaluarachchi, and Ungtae Kim, 2010. Multi‐Criteria Decision Analysis of Treated Wastewater Use for Agriculture in Water Deficit Regions. Journal of the American Water Resources Association (JAWRA) 46(2):395‐411. DOI: 10.1111/j.1752‐1688.2009.00409.xAbstract: Coastal regions such as the Gaza Strip of Palestine with limited freshwater supply suffer significantly due to the rapid depletion of water levels, seawater intrusion, and increased water demands. In such regions, use of treated wastewater (TWW) is a viable option if public health issues are addressed. The goal of this paper is to address the use of TWW in agriculture while considering net benefit, economic efficiency of water use (EEWU), environmental goals, and public health risks. The proposed methodology considers public health risk assessment and multi‐criteria decision analysis to assess the beneficial use of TWW in agriculture. The methodology was demonstrated for the Gaza Strip. The health risk assessment suggests that increasing the elapsed time between irrigation and consumption and switching from surface to sprinkler and drip irrigation are practical measures to reduce public health risks. The optimization and decision analyses show that proper allocation of freshwater and TWW and distribution of land area by crop type can significantly increase the net benefit and EEWU. In most cases, net benefit increased by 44%, groundwater use reduced 29% while increasing the EEWU by threefold compared with the existing conditions. The multi‐criteria decision analysis with weighted goal programming can develop flexible management options that considers a given decision‐maker preference. When groundwater abstraction for agriculture reduced from 57 to 36 Mm3 as per decision analysis, the corresponding area below mean sea level decreased by 58% indicating significant aquifer recovery.

Post-treatment of UASB reactor effluent in waste stabilization ponds and in horizontal flow constructed wetlands: a comparative study in pilot scale in Southeast Brazil

The results of a 20-month period study in Brazil were analyzed to compare horizontal-flow constructed wetlands (CW) and waste stabilization pond (WSP) systems in terms of land area requirements and performance to produce effluent qualities for surface water discharge, and for wastewater use in agriculture and/or aquaculture. Nitrogen, E. coli and helminth eggs were more effectively removed in WSP than in CW. It is indicated that CW and WSP require similar land areas to achieve a bacteriological effluent quality suitable for unrestricted irrigation (10(3) E. coli per 100 mL), but CW would require 2.6 times more land area than ponds to achieve quite relaxed ammonia effluent discharge standards (20 mg NH(3) L(-1)), and, by far, more land than WSP to produce an effluent complying with the WHO helminth guideline for agricultural use (< or =1 egg per litre).

Multi-stakeholder processes for managing wastewater use in agriculture

In Drechsel, Pay; Scott, C. A.; Raschid-Sally, Liqa; Redwood, M.; Bahri, Akissa (Eds.). Wastewater irrigation and health: assessing and mitigating risk in low-income countries. London, UK: Earthscan; Ottawa, Canada: International Development Research Centre (IDRC); Colombo, Sri Lanka: International Water Management Institute (IWMI).

Attitudes and actions of participants in multi-stakeholder processes and platforms

Multi-stakeholder processes (MSPs) and platforms are being used to address various aspects of water management. They have been championed as a way to improve planning and coordination to involve marginalized groups, and to increase learning and uptake of innovations. Between 2005 and 2008, a project called ‘WASPA Asia’ established multi-stakeholder platforms in two cities, Kurunegala in Sri Lanka and Rajshahi in Bangladesh, to address wastewater use in agriculture and its impact on farmers' livelihoods. This paper presents findings on the benefits and constraints of a particular MSP around a ‘Learning Alliance’. It also describes and analyzes the methodology used to obtain findings and suggests ways in which such a methodology could be used to improve results of MSPs. The paper indicates that the obvious merit of MSPs is in providing spaces for information sharing and awareness-raising. In time, MSPs can evolve to bring about changes in stakeholders' attitudes and actions but in many cases they are established around short-term projects, which limits their potential for (institutional) change. Given this constraint, attitudinal change and a better understanding of the issues amongst stakeholders are major accomplishments. Analysis of the methodology used for the review shows the benefits of regular joint monitoring, open communication, and the usefulness of relatively simple tools such as ‘change stories’.