hello there, I was able to find a link with some quick google, and here's the link to a article : https://www.researchgate.net/publication/249018516_Planning_and_design_of_urban_drainage_systems_in_informal_settlements_in_developing_countries

2.2 Community-based initiatives Due to the lack of intervention from local government, attempts to improve drainage are often made by local residents and elected representatives. Such local initiatives can only work if discharge to a local drain or drainage channel is possible. Depending on the leadership and social cohesion, some community-based organizations are more successful in encouraging collective action but assistance from a NGO is often needed to help these initiatives. However, these are often piecemeal approaches and drainage constructions are often disadvantaged by the lack of a secondary network with the capacity to accept increased flows.

(PDF) Planning and design of urban drainage systems in informal settlements in developing countries. Available from: https://www.researchgate.net/publication/249018516_Planning_and_design_of_urban_drainage_systems_in_informal_settlements_in_developing_countries [accessed Nov 14 2018].