Vetiver Wetlands: A Simple, Nature-Based Solution for Sustainable Coffee Production
TechnoServe is helping coffee farmers adopt an innovative, natural, and low-cost solution to prevent water and soil pollution.
In October, TechnoServe Global Coffee Sustainability Director Carole Hemmings will present at the Swiss Coffee Trade Association’s NextGen Sustainability Contest. She will share TechnoServe’s innovative work helping farmers plant vetiver wetlands to treat the wastewater from coffee processing. Below, Carole answered questions about why this innovation is important for protecting the environment and supporting farmer livelihoods.
How does coffee wastewater impact the environment?
Coffee can be a very nature-friendly crop. For example, it thrives under a forest canopy, and can, in many places, be grown organically without synthetic fertilizers or pesticides. However, one of the most common ways of processing coffee after harvest can pollute waterways and soils.
About half of the world’s coffee is what is called washed: the freshly picked coffee cherry has the outer skin, the pulp, removed, passes through fermentation, and is washed, leaving the coffee bean and just an outer husk. This wet milling process helps to preserve the quality of coffee and ensure that farmers earn better prices.
However, as the name suggests, wet milling uses water–often a lot of water. For example, in Peru, farmers collectively use an estimated 11 million liters of water each year to process their coffee.
During the wet milling process, water becomes contaminated from the coffee pulp and can pollute soils, streams, and rivers if released. Untreated coffee wastewater can make animals sick, make water sources unsuitable for any kind of domestic use, and harm biodiversity. It also impacts quality of life by attracting insects and causing a terrible stench during harvest season.
What are the available solutions for water pollution in coffee production?
Unfortunately, smallholder farmers and small cooperatives have not had affordable solutions to address the problem. For example, more ecologically friendly processing equipment is often unaffordable for these groups.
In Peru, some farmers would construct sedimentation ponds to collect the wastewater, but these often overflow, can be dangerous for children, and are not very effective. As a result, we found that 85% of farmers in Peru were not treating their wastewater at all; instead, it would flow directly into soils and waterways.
This challenge led us to develop the vetiver wetland solution as an effective, affordable way to deal with coffee wastewater.
What is vetiver grass, and how does it help reduce water pollution in coffee farms?
Farmers have used vetiver grass for thousands of years, but only recently have we used it to address coffee wastewater contamination. Vetiver is originally from South Asia, and because it has deep, strong roots and is resilient, farmers have long used it to combat soil erosion.
Those same qualities make it a great tool for dealing with coffee wastewater. Its deep, strong roots help it filter and absorb the wastewater. If farmers plant a wetland of vetiver grass, it can effectively prevent wastewater from contaminating the soil or waterways. Additionally, because it’s a low-tech solution, it is affordable to build and easy to maintain.
How is TechnoServe helping farmers implement vetiver wetlands in East Africa and Latin America for sustainable coffee production?
TechnoServe developed the approach in partnership with Ethiopia’s Jimma Agricultural Research Centre more than a decade ago. In Ethiopia, coffee is washed centrally–that is, farmers deliver their freshly harvested coffee cherry to a cooperative or private business that processes the coffee. During harvest season, the coffee wastewater produced by these wet mills can make entire stretches of rivers unusable.
Working with several partners, such as Mother Parkers Tea & Coffee, we have helped more than 150 of these Ethiopian wet-milling businesses install large vetiver wetlands. We worked with the University of Hawassa to test the impact of these vetiver wetlands on local river water quality and found that it essentially eliminated the water pollution caused by coffee processing.
Based on that success, we looked to adapt the approach for Peru. There, farmers process their coffee individually on their own farm, so we needed to scale down the wetlands. We tested to see whether a small, 12-square-meter wetland would be effective at treating the volume of wastewater that individual farmers were generating–and it was. Best of all, the construction cost for a farmer is under $100.
Through the CAFE program, a USAID initiative supported by JDE Peets, TechnoServe has helped more than 1,500 farmers build vetiver wetlands and has even helped cooperatives establish vetiver nurseries so that farmers can plant additional wetlands in the future.
How do vetiver wetlands help fight water pollution and alleviate poverty in coffee farming communities?
The clearest benefit of vetiver wetlands is to the environment and the communities that depend on them, but they can also improve coffee farmer incomes. In Ethiopia, wet milling businesses can be temporarily shut down by local authorities for causing water pollution, with negative consequences for the workers at those businesses and the farmers who sell their coffee there. With vetiver wetlands, these businesses don’t run that risk.
In Peru, smallholders who plant vetiver wetlands can earn environmental certifications that open up new markets and higher prices for them. For example, the Rainforest Alliance has recognized the approach as meeting its standards for certification.
