System level water use efficiency of rural water supply systems in rural Colombia: a top - down analysis

In developing countries, such as Colombia, the majority of the rural water supply systems (RWSS) emerge from the water needs of the community, in order to transit from manual water collection to piped systems. The communities usually construct their water supply system and assume the responsibility of the system. How big these system grow and how well these are maintained are key to how well these systems serve its communities. This paper explores whether the scale of a system, i.e. the size of the system and the number of water users, is an emergent property of the human-water system and that the maintenance of a RWSS depends on this emergent property. Key questions addressed here are: what factors control the scale of a system and how these factors affect the maintenance of the system.

Eight RWS systems located in the rural area of two municipalities, Restrepo and the rural area of Cali in the Valle del Cauca province in Colombia, are investigated to compare and contrast the systems and associated factors such as location, occupation and income distributions of the communities. Nearly 900 households representing the population are surveyed. Even though the RWSS are located in the same region, water use efficiencies (indicator of system maintenance) are different from one system to another.

Rarely, the distance from the RWSS to urban areas is considered to analyse how well a system is maintained. The results highlight that the locations of the systems, dominant occupation and income levels, as a result,  of the communities play an important role because it determines the surplus that communities are able to muster to maintain as well as grow the systems. The surplus is less in remote areas compared to those close to the peri-urban areas while the maintenance costs are similar. As a result, factors are identified that affect the scale and water use efficiency of the studied RWSS in the Valle del Cauca province in Colombia.