Water use has been growing at more than twice the rate of the population increase during the last century. In rapid growing urban centres, water has become a fragile and scarce resource in a competing environment.
Management of water resources has become an urgent issue as urban and peri-urban farmers often apply water from municipal sewage, mostly in its untreated form, increasing the risk for illnesses to farmers and consumers. For more information browse Wastewater and sanitation.
In urban and peri-urban agriculture, locally-adpated small scale irrigation and plant production methods and schemes are possible solutions to save water. Low cost water-savings technologies such as underground and drip irrigation can increase water efficiency as well as allowing safe use of low quality water resources. Drip irrigation infrastructure can be manufactured from existing local products, such as using porous ceramic containers or pipes with holes in which water is dripped onto the soil above the root zone only. Drip irrigation practices offer the opportunity of spot irrigating and fertilizing when using wastewater, often utilizing a third of the water used in conventional irrigation practices. Drip irrigation also offers the added benefit of minimizing the contact of the wastewater and the crop, decreasing the likelihood of contamination. In cases of salt-tolerant crops, brackish water can be used in localized irrigation schemes.
Urban and peri-urban horticulture and micro-gardens such as s imple hydroponics may be utilized to add economic and nutritional benefits by securing year-round supply of fresh produce to urban populations. Simple hydroponics (SH) promotes water savings in recycling and decontamination of water and will facilitate growing of plants in areas with marginal conditions for crop production, such as adverse climate, soil, space limitations in cities, water scarcity, and pest occurrences. At the same time, SH generates local markets in supply food chains. Simple hydroponics can be considered an effective alternative to be integrated in food security and nutrition rural and peri-urban development programmes with low-resource populations living under poverty conditions.