19th April 2024

Swales @ Save

The school is suffering from bad gully erosion caused by the steep slopes and heavy rainfall. The intention is to trap it, encourage it to soak into the ground and to utilise the rainwater to develop a forest garden system which will help feed the school. There is a background of childhood undernourishment caused by protein deficiency which can have long term impacts on childhood development.

The team will develop a series of Swales across the school grounds making sure if one overflows then the next one can catch any excess rainwater. As the swales develop the whole school environment will slowly change, providing shade and tree cover which will also help break the force of the heavy seasonal rains before they hit the ground.

There is always much to learn and each circumstance is different. I suspect at Save School our swales will need to be wider and have a higher bank 70 cm maybe and at least a 1m trench, as rain can be very heavy at times. Once the swale is fully established it will be very strong but at first before the plants develop a strong root system we have to be careful.

It will also be interesting to consider the mix of trees and other plants we use, for example leucaena, pictured below, one of the fastest growing trees in the world, can be heavily coppiced and fixes nitrogen and helps build soil. The S39 team had success with the clay thermal mass rocket stove on the refugee project and perhaps the narrow diameter wood from managed coppice could be the ideal fuel for it.