Guidelines for shell colony (housing and landscape) site guidelines explain both site moves and building characteristics. The Mithi River slum population will be moved to allow for river expansion to increase drainage (upper diagrams). Ideas about open space within the building are extracted from Mumbai precedents.

Block section: section cutting a typical block, from public street, through the building courtyard, into the semi-public green space, the building is raised, allowing water to flow to the green space, entering the initial catchment tank (right tank) then filtered (left tanks).

Drainage and filtration axoometric: this axonometric walks rainwater through the underground filtration system to a play pump, and to the slow-sand-dobi-ghat filtration tank. Grey water from apartments or laundry can be re-entered into this system.