The Wet Mills

Watch part 4 of
the documentary

Processing the coffee

Once the coffee has been harvested, it is sold to the wet mills.
There the coffee is processed in four key steps:

processing plant
processing plant
processing plant
processing plant

Harvested coffee cherries are fed into a pulping machine that separates the bean from the fruit. The pulp is carried away in the wastewater, while the bean is sent to the fermentation tanks. The beans are also sort by weight at this stage.

2. Fermenting

The beans may sit in the fermentation tanks for between 8 to 72 hours, depending on the efficiency of the pulping machine and several environmental factors. Here the mucilage layer is broken down and the coffee’s flavor is naturally enhanced.

3. Washing

After fermentation the beans are washed to remove the remains of the sticky mucilage layer that began to break down in the fermentation tank. Laborers rake the coffee beans through water channels to clean them.

4. Drying

The washed coffee, known as parchment, is taken away and spread on drying trays where it dries naturally in the sun. Laborers turn the coffee by hand to ensure even drying and remove damaged, broken or overripe beans.

The Problem

There are more than 220 wet mills in the Sidama coffee region and each of them is an important part of the local economy. A good harvest sees the wet mills along the river bustling with activity as scores of day laborers wash and sort the coffee beans.

Unfortunately, a good harvest and plenty of work processing the coffee also means the wet mill is producing large amounts of organic waste that sits in the wet mill lagoons and seeps back into the river.

When pollution from the wet mills became unbearable the villagers would complain to the local government. In turn, the officials often closed the wet mills down temporarily, a solution that did not make anyone happy because of its damaging effect on the local economy.

waste water

Wastewater and coffee cherry pulp.

But there just didn’t seem to be a better option.