Stabilization Ponds in The Gambia

Hello there, I am from Gambia and have been working in the WASH sector. Most of the population, >90%, use on site sanitation (toilets and some with soakaways and others with holding tanks). The sewerage network is provided for the tourism area (Hotels are connected to a waste stabilization pond). The pond is the only treatment plant available in the area. Collected sewage from households also ends up at the pond, which initially was designed for only waste from the tourism area. The industries also smuggle and dump at the ponds at times. The ponds currently produce so much odour that it raises alarms and authorities are watching. Kindly advice on suitable technology for this community? What ways can treatment be rehabilitated at the ponds? Thank you