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To reduce dependence on freshwater and maintain a constant source of irriga-tion water throughout the year, waste waters of varying qualities can be used in agriculture. Generally, only waters that have had secondary treatment (i.e. physical and biological treat-ment) should be used to limit the risk of crop contamination and the health risk to workers. There are two kinds of irrigation technologies that are appropriate for using treated wastewa-ters: 1) Drip irrigation where the water is dripped slowly on or near the root area; and 2) Surface water irrigation where water is routed overland in a series of dug channels or fur-rows.
None of the options were relevant for Irrigation.