Certainly. Below is a strict, faithful English translation of the new article you provided, maintaining the original narrative tone, technical accuracy, and all details without any extrapolation.
The Wastewater Revolution on Coffee Farms: How Smallholder Farmers in Latin America Are Boosting Incomes Through Wastewater Treatment
Behind every cup of coffee, more than 80% of the cherry goes unnoticed.
In the early morning in Huila, Colombia, the mountain mist has not yet lifted, and coffee growers are already pouring baskets of ripe red cherries into the pulping machine. A few hours later, the skin and pulp are flushed into troughs, while the mucilage layer quietly ferments for one to two days in fermentation tanks, releasing a sour, pungent odour. By the time the final rinse with clean water is done, what is actually sold and eventually becomes the coffee in our cup accounts for less than one‑fifth of the fruit’s total weight.
What about the rest? Pulp, mucilage, and fermentation wastewater — these “by‑products” that make up over 80% of the fresh cherry weight have long had only one fate: being dumped into nearby streams.
This is not an isolated scene. From the western highlands of Guatemala, to the dry corridor of Honduras, to the cacao‑growing belt along the edge of the Peruvian Amazon, the same picture repeats daily. And these casually discarded materials are precisely the starting point of this story — because they are far more valuable than they appear.
Underestimated “pollution” is actually wasted “resource”
The wet processing (washed) method is the standard process for specialty coffee in Latin America, as it produces a cleaner‑cupping “washed coffee”. But this process comes at the cost of enormous water consumption and pollution load: processing one tonne of fresh coffee cherries typically uses 2.3 to 23 cubic metres of water; and the mucilage wastewater from fermentation has a Chemical Oxygen Demand (COD) that can spike to 18,000–45,000 mg/L, dozens of times that of typical municipal sewage. It is highly acidic, almost a “liquid jam”‑strength high‑strength organic effluent.
If discharged directly, the consequences are obvious: eutrophication of rivers, fish kills, groundwater contamination, and threats to the water safety of downstream communities.
In coffee‑producing regions such as Ethiopia, researchers have systematically documented the damage wet‑processing wastewater does to downstream river quality; and while monitoring data in Latin America are more fragmented, the pollution mechanism is exactly the same — the same mucilage, the same fermentation process, the same acidic effluent.
Yet, viewed from another angle, this “wastewater” is actually an untapped mine: it is rich in sugars, organic acids, and fibre, making it an excellent feedstock for anaerobic biogas production; the settled pulp and mucilage, after drying and composting, make a good organic fertiliser.
The issue has never been “whether it can be turned into something useful”, but rather “whether someone is willing to build the bridge”.
Colombians began building that bridge 40 years ago
In the 1980s, Colombia’s National Coffee Research Centre, Cenicafé, launched a research and development project called BECOLSUB (Ecological Processing and By‑product Utilisation Technology).
Its design logic was very straightforward:
first, mechanically separate the skin and pulp with minimal water use; then mix the mucilage with the pulp and compost them on site. After more than a decade of iteration, the technology eventually reduced pollution by over 90% and cut water consumption per kilogramme of dry parchment coffee from over 40 litres in the traditional process to less than 1 litre. For a medium‑sized coffee farm, the pulp and mucilage from one harvest can provide enough organic fertiliser for a significant portion of its coffee land, directly saving a substantial amount on chemical fertiliser purchases.
The widespread adoption of this technology has also been supported by a policy instrument that is often overlooked: Colombia’s “retributive fee” (Tasa Retributiva). This system dates back to the 1993 Environmental Basic Law, and its core principle is “the polluter pays” — any entity discharging pollutants into water bodies, whether a factory or a coffee processor, must pay fees based on the actual load of BOD and suspended solids discharged.
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Moreover, even if the discharge exceeds the standard, fines and fees are levied simultaneously; paying the fee does not make the discharge “legal”. In other words, this system turns “treating wastewater” from a mere environmental slogan into a real bill that has to be paid. This is why, for Colombian coffee growers, treating wastewater as a resource is essentially about saving money, not just doing good.
In 2026, a new facility adds a fresh chapter to this story
On 26 May this year, the National Federation of Coffee Growers of Colombia inaugurated the first “circular bio‑economy” processing centre in the Federation’s nearly 100‑year history, located in the town of Gigante, Huila. Built by Almacafé and operated by the Cooncentral cooperative, the plant has a daily processing capacity of 35,000 kg of fresh coffee cherries.
Its greatest significance lies in compressing the traditional 15‑to‑20‑day process of pulping, fermentation, washing, and drying — which growers used to do on their own — into a single day of standardised procedures carried out centrally at the facility. Meanwhile, the by‑products — pulp, mucilage, and husks — are systematically converted into organic fertilisers, biofuels, animal feed, and even energy gel for human consumption; the Federation also plans to install an ethanol distillation column.
The Federation’s general manager stated bluntly at the inauguration that the sole purpose of this facility is to increase the net income of coffee growers — there is no more important metric than that.
The timing is telling. In the first half of 2026, domestic coffee purchase prices in Colombia fell by more than one‑quarter from their peaks at the start of the year, with a record Brazilian harvest and peso appreciation further squeezing already stressed growers, while meteorological agencies have warned of a possible El Niño event in the second half of the year. In a year of income pressure, a “second income curve” — biogas, organic fertiliser, animal feed — that growers can control themselves, unaffected by international futures prices, becomes especially precious.
In the cacao sector, the same story is unfolding
Turning to cacao: in Peru, cacao fermentation generates a highly polluting wastewater locally known as aguas mieles (“honey water”), whose composition is almost identical to coffee mucilage wastewater — high in sugars, high acidity, and high organic load.
With support from a fair‑trade project, the Sol y Café cooperative built facilities to treat this wastewater, converting it into useful products such as organic fertiliser. The more direct benefit: after the treatment facilities came online, the 184+ tonnes of cacao beans processed by 175 smallholder families in the cooperative all achieved the highest grade of “Fine Aroma” — which means they can command higher prices, truly raising farmers’ incomes. This is not a by‑product of an environmental project; it is the project’s core outcome.
In Central America, similar logic is quietly taking hold in small‑ and medium‑sized coffee processing plants: some farms in Honduras, Nicaragua, and Guatemala have begun using biodigesters to treat coffee processing wastewater, with the biogas produced used directly for cooking, replacing firewood that would otherwise be obtained by cutting trees.
For a family in a remote mountain village, this means the kitchen is no longer filled with smoke all day, wives and children no longer have to walk kilometres up mountain paths to gather firewood, and pressure on forest resources is also eased.
The true significance of this “wastewater revolution”
The wastewater treatment rate in rural Latin America has long lingered in single‑digit percentages, and infrastructure investment will hardly cover smallholders scattered across mountainous terrain in the short term.
However, coffee and cacao processing wastewater has a unique characteristic: it is extremely concentrated in pollutants, yet highly biodegradable; and it is generated at highly concentrated points — right at the growers’ own processing stations or cooperative yards.
This is precisely the scenario where low‑cost, easy‑to‑maintain technologies such as small‑scale anaerobic digesters and simple composting can perform best — no expensive municipal sewer networks or complex maintenance teams are required.
More importantly, this path re‑couples two objectives that are often seen as conflicting: environmental management and farmer income enhancement. Local industry bodies also view this circular bio‑economy model as a replicable template that can be rolled out across coffee‑growing regions throughout Latin America.
So the next time you enjoy a cup of coffee or hot chocolate from Colombia, Honduras, or Peru, you might pause to think: behind that beverage, besides the hands that grew it, there is also that wastewater — once regarded as a nuisance, now being revalued — quietly rewriting the balance sheets of those mountain farmers.
