text size: smaller reset larger

 

 

Using water wisely to feed growing cities

In the town of Soukra, hundreds of low-income families live off the crops they grow (© M Bouraoui and B Houmane)
In the town of Soukra, hundreds of low-income families live off the crops they grow
© M Bouraoui and B Houmane

North Africa contains 5 per cent of the world's population but only has 1 per cent of the world's available water resources. In Tunisia, water availability is as low as 350 m³ per person per year, but rapid urbanisation and climate change are placing further stress on water resources and food production. Use of treated wastewater for irrigation has helped to sustain agriculture in peri-urban areas, but severe government restrictions on wastewater use are constraining production.

In the town of Soukra, six kilometres from the capital city, Tunis, hundreds of low-income families live off the crops they grow. In recent years, however, rapid urbanisation has caused the city to expand, encroaching on farms, driving land speculation and threatening the livelihoods of Soukra's farmers. Since the 1990s, nearly 30 per cent of arable land has disappeared. Farmers are also facing significant water stress: climate change has altered rainfall patterns, causing more extreme droughts and floods and leading farmers to draw more water from wells. As a result, saltwater from a nearby lagoon has been seeping into the groundwater, leaving some fields waterlogged and others too salty to grow healthy crops.

Greenhouses and wastewater

Rainwater is stored in ground-level basins adjacent to farmers' fields and is delivered to crops (© M Bouraoui and B Houmane)
Rainwater is stored in ground-level basins adjacent to farmers' fields and is delivered to crops
© M Bouraoui and B Houmane

With funding from Canada's International Development Research Centre (IDRC), the Tunisian NGO Club UNESCO/ALECSO pour le savoir et le développement durable (FTCUA Tunisie) set out to find comprehensive ways to mitigate the environmental threats farmers face, while helping them secure and improve their livelihoods. "We spent a year with experts, researchers, regional and local NGOs and the municipality to understand the origin of these problems, the farmers' perspectives and their aspirations for the future," says Moez Bouraoui of FTCUA Tunisie and president of the Urban Agriculture Association of the Middle East and North Africa.

This led to the development of a plan that would address environmental threats to agriculture while improving farmers' incomes. The idea was to deploy new, environmentally-sustainable sources of water for irrigation to increase agricultural production, and create small businesses for the farmers who had largely been growing subsistence crops. "These farmers only have small plots ranging from 1,500 m² to one hectare," Bouraoui explains, "so we opted for greenhouses which help conserve water, protect crops from grazing animals and theft, and allow for more intensive farming. This much more intensive form of agriculture has vastly increased yields by allowing crops to be grown in the earth and suspended above ground."

With greenhouses, crops can be grown in the earth and suspended above ground (© M Bouraoui and B Houmane)
With greenhouses, crops can be grown in the earth and suspended above ground
© M Bouraoui and B Houmane

Technicians then installed ground-level basins adjacent to farmers' land to store rainwater and deliver it to crops. This water is directed to the greenhouse crops using highly efficient micro-irrigation. "After a few months of experimentation and research, we installed rainwater collection systems on the greenhouses," Bouraoui adds. "Gutters built into the greenhouses' support structure channel the rain into storage tanks, which can meet up to 60 per cent of its water needs." Wastewater - including water used for household bathing and cleaning - was also captured, filtered and used for irrigation. Following Tunisia's strict regulations on wastewater use, it is only used to grow flowers, which are a lucrative crop. To restore saline soil, fresh earth was added and olive trees planted, which will tolerate a large range of soil conditions and can be irrigated with wastewater.

Strawberries and snails

Greenhouses usually have to be moved every five years to avoid soil depletion, but this is impossible because of a lack of space. Farmers began to experiment with lucrative crops that could be grown in containers above the soil - such as strawberries and lettuces - to allow the ground to lie fallow. Snails, which provide fertiliser, are also farmed in containers. Farmers who once grew crops for subsistence are diversifying and cultivating more cash crops, including ten kinds of fruit and vegetables, which they sell in nearby markets. Greenhouses have also extended the growing season and increased incomes, as farmers can earn much more for produce such as tomatoes, when they are out of season. For example, one greenhouse produces six tonnes of tomatoes, worth around US$4,600. Farmers who were once amongst the poorest are enjoying better lives. One mother paid for her daughter's wedding, others have expanded their homes. "One of the most tangible signs of success," says Bouraoui, "is that some farmers are reinvesting their profits into building more greenhouses."

Snails, which provide fertiliser, are farmed in containers (© M Bouraoui and B Houmane)
Snails, which provide fertiliser, are farmed in containers
© M Bouraoui and B Houmane

The research team has worked closely with the city government to help it recognise the ecological and economic value of urban agriculture, and to include small-scale farming in land use planning. "Together we thought about how to develop a structure that could unite the farmers, that could defend their interests, and provide them with services to support the development and growth of their businesses," Bouraoui explains. "We put in place a cooperative which is gradually taking over the research and gives farmers a stronger voice in local decision-making. In some ways, this is one of the greatest achievements of the project."

This model of urban agriculture and the technical innovations that have been produced are now being disseminated throughout Tunisia through mass media, journal articles, workshops and conferences. Through associations like the Arab Network for Urban Agriculture, the knowledge gained in Soukra is being shared with groups throughout the region. "The solutions pioneered in Soukra provide excellent examples for countries in the region coping with water scarcity and climate change," Bouraoui concludes.

Date published: May 2013

 

Have your say

 

The New Agriculturist is a WRENmedia production.

This website uses cookies to improve your experience. By continuing to browse the site you are agreeing to our use of cookies.
Accept
Read more