Rubbish, waste.
Bola is where the household waste goes, and the word turns up in the names of the people and services that deal with it.
Kaya bola are the informal collectors — often young men with carts — who take household waste away for a small fee per bag. They operate alongside the formal collection companies contracted to the district assemblies, and in many neighbourhoods they are what actually happens.
Never put bola in a gutter. Accra’s open storm drains are its drainage system, and blocked drains are a large part of why the city floods.