The importance of storage becomes clear, when it is not available. In district 9 of Cochabamba, lack of barrels to fill with tanker water is one of the main factors for the limited engagement with productive activities by users who rely on tanker systems. Not having storage capacity in South Africa was found to increase people’s vulnerability (Maluleke, 2007).
3.3.5 Water treatment technologies Another group of technologies is related to the treatment of water, mainly to achieve drinking water quality for at least 3 lpcd in multiple-use systems. Obtaining such quality is a concern in surface water systems and in open unprotected groundwater wells. The case studies highlighted the following (combinations of) technological options that operate at different scales. Protecting the spring or source: Building a protection box or screen around the spring with a hygienic outlet is possible when there is a clearly defined spring and was done in all Nepal cases and at various springs in Eastern Ethiopia (Scheelbeek 2005, Ebato 2008). Proper protection may reduce the need to treat relatively clean surface water sources. Central treatment of water: Central treatment is the approach followed in most urban areas where water of drinking quality is delivered to all houses. This is also the most common approach in rural communities that rely on surface water systems, such as those in Colombia. However, treatment plants at the beginning of a piped system limit easy access to larger quantities of water and may limit multiple use. As people prefer larger quantities over higher-quality water, they may construct new pipes to bypass the plant. In La Castilla (Colombia), the municipality’s Health Secretary wanted to build a treatment plant and to forbid the use of water for irrigation. The community rejected the entire plan (Sánchez et al., 2003). Users trust that water is potable and drink it without boiling. However, not all treatment systems work well. In addition, re-contamination may occur after treatment, and the handling of water in the household may be unhygienic. In Lege Dini, Ethiopia, water from a clean source (e.g. a borehole in Ajo or a protected spring in Kora) became as contaminated in the containers used to carry it as water from surface water sources (Scheelbeek, 2005). Chlorination of community systems is often promoted, even in groundwater-fed systems, such as in Kikwari, India. However, chlorinated water has low acceptability to users. Moreover, as in various communities in Colombia, users don’t want to spend money on chlorinating all their water, when only a fraction is for drinking or cooking. Partial central treatment with separate distribution systems: It is possible to treat part of the water centrally and distribute treated and untreated water through separate distribution systems. We encountered several examples in our case studies. One community in Colombia, with a predominant indigenous population, was more interested in getting water for irrigation than high-quality domestic water. However, the drinking water project didn’t want users to use this expensively treated water 118