Basin Terracing- Cleaning Nairobi's Drinking Water

Farm Technology Helps Clean Up Nairobi's Drinking Water

Samuel Kinuthia knows how to make the most of technology. Using a technique called basin terracing, he has boosted his income at his farm in Murang'a county, and helped provide Kenyans as far away as Nairobi with better access to clean drinking water.

Kinuthia and a group of 300 farmers in Kiaruta village are turning hilly land into more productive farmland through basin terracing. It also reduces soil erosion, which can choke central Kenya's rivers and pollute drinking water.

On a sunny morning, Kinuthia and two employees are preparing a fresh strip of land to sow crops on his three-acre farm.

First they dig across a hilly patch to make it into a flat terrace. They then dig square holes to form basins on the strip, where Kinuthia will plant vegetables.

"I used to plant maize and beans but I could not harvest much," he said. "With basin terracing, I can plant fresh produce like tomatoes, kale and onions. Both the harvest and the resulting income improve because there is a ready market."

Fred Kihara, water fund manager in Kenya for The Nature Conservancy (TNC), an international environmental organisation, explained that the technology reduces the amount of soil being eroded away into rivers.

"It also increases the amount of water that is being retained in the soil," he added.

A 2015 study by TNC says the Upper Tana basin - which provides water to an estimated 9 million Kenyans - is a watershed under pressure.

About 65 percent of the farmers questioned by the group said the productivity of their land had declined even though they use more fertilisers than five years ago. Overall, 80 percent reported a decrease in rainfall in recent years.

From Kinuthia's farm in the Upper Tana basin, the view is of stretches of hilly terrain that have been stripped bare of trees. The red soil is easily blown away or eroded.

PROTECTING SOURCE WATER

Farming on hilly land has increased the amount of soil ending up in rivers that feed the country's largest water reservoir, the Ndakaini dam, in central Kenya.

Source: AllAfrica