Once we got back from Kigali with all the materials (and Alison!) we made some final touches on the system at Kigogo and reopened it for business. I’ll explain some of the problems of the system and how we went about solving them.
The main civil works issues that Kigogo had when we arrived in Banda were as follows:
1. Water overflowed at several points along the channel in the rainy season, which caused hillside erosion
2. The site operator had no robust way to control flow into the system; his method of stoping flow to the settling tank was a combination of mud and leaves inserted into the channel
After brainstorming, weighing specification importance and comparing design alternatives like we’ve been taught at Thayer 🙂 we decided to construct a spillway just before the most severe point of rainy season overflow. The spillway was designed to let 12 L/s continue towards the settling tank while sending the remaining water back to the river. Downstream of the spillway, a sluice gate allows the site operator to fine tune the amount of water continuing to the settling tank and also stop the water completely when the system needs to be turned off.
The finished product seems to work pretty well. The real test will be during the rainy season though. We hope to get some pictures and reports of how it’s working in a few months. We did get great feedback from the community already though. When I was buying eggs, the shop owner told me, “God bless you, Kigogo is amazing.” June also got several handshakes and blessings at the opening of the Kigogo, when the site successfully charged all types of batteries faster than it ever had before. It is exciting to see the community respond positively to our work!