About Housing First. 1  According to the National Alliance to End Homelessness, Housing First is an approach to ending homelessness that centers on providing people experiencing homelessness with housing as quickly as possible â and then providing services as needed.
In human geography, a catchment area is the area from which a city, service or institution attracts a population that use their services. For example, a school catchment area is the geographic area from which students are eligible to attend a local school. Supermarkets, on the other hand, have a much lower density, with catchment areas of several neighborhoods (or several villages in rural areas). 2  This principle, similar to the central place theory, makes catchment areas an important area of study for geographers, economists, and urban planners.
A drainage basin or catchment basin is an extent or an area of land where surface water from rain, melting snow, or ice converges to a single point at a lower elevation, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean.ach drainage basin is separated topographically from adjacent basins by a perimeter, the drainage divide making up a succession of higher geographical features (such as a ridge, hill or mountains) forming a barrier.