Trenches save surface run-off water for semi-arid irrigation

Banana Muia Kusenga By Laban Robert.JPG

Muia Kusenga with Festus Mutemi. The farm has more than 10 trenches ans a tank that store water for irrigation for more than three months. Photo by Laban Robert.

As the long rain seasons starts, 83-year-old Muia Kusenga is removing the accumulated silt from the trenches  to create space for collecting run-off water from the a nearby road for later irrigation.

Kusenga, who has dug more than 10 trenches in his farm in Machakos County, says the water helps him in irrigating the fruits for about two months after the rains.

Besides, the trenches drain the excess water into a more than 100,000 litre tank within the farm for storage.

“This is not just soil, but rich nutrient silt from for my grapes, loquats, avocados, goose berries, among other fruits. Even if the rains disappear for one to months from June, I will be safe for another three months with irrigation from the trenches and the tank water,” he said.

Leaves and other organic matter accompanying the surface run-off water keep rotting for the entire duration the water is in the 4feet to 5feet deep trenches. Together with the silt, the farmer says the organic fertiliser is ‘concentrated’ with minerals.

The trenches run end across the farm. They are interconnected at the ends so that after the first one is filled, the excess water flows to the next one.

The small ‘Garden of Eden’, as he calls this farm, survives through the dry seasons experienced in the semi arid county.

In other shallower trenches, he has grown yams. Yams do well in water-rich soils. But he says the moisture that is within the trenches is enough to sustain the crops until harvesting.

There are more than 50 fruit varieties grown this farm of about five acres. The colonial extension officer said he learnt from the Britons that “lack of rain does not mean lack of farming”.

The Kenya Meteorological Department has predicted that the long rains may not be intense as previous years, but they will continue until June this year.