Private micro-irrigation costs using reclaimed water

Abstract

The cost of reusing water in micro-irrigation at the field level has not been studied in depth although the use of effluents in agriculture is a viable alternative in areas where water is scarce or there is intense competition for its use. The aim of the present study is to analyse the private costs of water reuse in micro-irrigation in an experimental plot. This analysis is intended to provide information about the decision a farmer would make when the choice to use conventional or reclaimed water is guided by cost criteria. The components of the total costs of different combinations of four types of filters and five emitters that can be installed in micro-irrigation systems using reclaimed water have been studied with the data obtained from an experimental plot in conditions similar to those of fruit orchards. Different scenarios that compared the costs of using conventional or reclaimed water in terms of water price and nutrient content were also studied. The results show that a proper combination of filters and emitters can save up to 33% in irrigation costs. Capital costs and maintenance costs were the most variable among the different combinations. Scenario analysis showed that the greater price of reclaimed water could be compensated by high nutrient contents, which would reduce fertilizer costs.Additional key words: clogging; drip emitters; types of filter; water economics; water reuse. ResumenCostes privados del riego por goteo utilizando aguas regeneradas El coste de la reutilización de agua en sistemas de riego por goteo a nivel de parcela no se ha estudiado en profundidad aunque la utilización de aguas residuales en agricultura es una alternativa viable en áreas con escasos recursos hí-dricos o con fuerte competencia por su uso. El objetivo del presente trabajo ha sido analizar los costes privados del uso del agua regenerada del riego por goteo en una parcela experimental. Se pretende que este análisis aporte información sobre cual sería la elección del regante según un criterio de costes si pudiera optar entre utilizar agua convencional o regenerada. Para ello, se analizaron los distintos componentes de los costes totales de diferentes combinaciones de cuatro tipos de filtros y cinco emisores comerciales, partiendo de los datos obtenidos en una parcela experimental en condiciones similares a las de una plantación de frutales. Se estudiaron también distintos escenarios en los que se comparaban los costes del uso de agua convencional o regenerada en función del precio de la misma y del contenido en nutrientes. Los resultados obtenidos indican que una correcta combinación de filtro y emisor puede ahorrar hasta un 33% de los costes de riego. Los costes de inversión y los de mantenimiento fueron los que más variaron entre las distintas combinaciones. El análisis de escenarios evidenció que el mayor precio del agua regenerada podría compensarse con una aportación elevada de nutrientes por parte de la misma, lo que permitiría reducir los costes de fertilización.Palabras clave adicionales: economía ...

Evaluation of Thirty-Eight Models of Drippers Using Reclaimed Water: Effect on Distribution Uniformity and Emitter Clogging

“…However, current water policies not only consider reuse as a viable option, but they strongly encourage increasing their use, as reflected in the relevant regional and national water plans. The use of effluents in agriculture is a viable alternative in areas where water is scarce or there is intense competition for its use [8]. In Spain, reusing treated water for agricultural irrigation, among other uses, is regulated by Royal Decree 1620/2007, of 7 December [9].…”

Pressure drop across sand and recycled glass media used in micro irrigation filters

“…However, sand media filters are often considered the standard for filtration protection of micro irrigation systems (Trooien & Hills, 2007) because emitters protected by these filters show low degrees of fouling (Capra & Scicolone, 2007; Duran-Ros, Puig-Bargu es, Arbat, Barrag an, & Ramírez de Cartagena, 2009a). Nevertheless, sand filters are usually more expensive than the other filter types (Pujol, Duran-Ros, Arbat, Ramírez de Cartagena, & Puig-Bargu es, 2011), and they are usually only appropriate for farms with high technical and professional standards (Capra & Scicolone, 2007).…”