Hydraulic ram pumps and Sling Pumps

meal a day and washing the dishes. Consumption reduction means first reducing the consumptionby the toilets. Flushing valves consume less than flushing cisterns, but they are not appropriatesince they require a permanent high water pressure not always available in developing countries.There are producers of toilets consuming 4 litres of water per flush in Sweden, Great Britain andWest Germany. Imports of this highly appropriate system into developing countries, where there is areal need to save water, should be encouraged. In Botswana this was done by the BotswanaTechnology Centre in Gaborone. This institution had discussions with wholesalers whom theypersuaded to import a reasonable number. At the same time the centre spread information aboutthis new system. Introduction of a new system like this takes time since people have to beconvinced that the higher investment really brings returns. But there is also something that can bedone about the existing highly wasteful cisterns. Some can be adjusted to lower levels of filling bybending the bow of the cistern float downwards. This results in stopping the filling water at a lowerlevel. It is also possible to put stones around the off-flow of the cistern. The volume of the stones(blocks) will be the volume of water saved, at the same time raising the water level to the adjustedcistern float. Depending on the type of cistern the consumption can be reduced to 7 or even 6 litres,but the cleaning effect of flushing is reduced since the toilet bowl is not designed for such lowconsumption.1.3.2 Bath or showerIt is often not realized that the amount of water consumed for one bath is sufficient for threeshowers. In consequence this would mean that houses should be furnished with showers ratherthan with baths. But baths have become a status symbol in many countries, and a high cost housemust be furnished with a bath. The amazing thing is that baths in Europe are rather out of fashionand much less used than showers which produce savings in both water and time. From the hygienepoint of view showers are better than baths. If a bath is installed this should always be done in sucha way that a shower battery is fixed, so that the bath can also be used for showers. At the same timethe built-in bath should be chosen carefully since the capacity varies substantially. Several devicesare on the market designed to reduce water consumption. Spray nozzles for showers, push buttontaps etc. might reduce consumption, but should be studied before use. When deciding on watersaving equipment one has also to consider the lime content of the water. Lime precipitates at 60 °C.This means that sensitive equipment in hot climates will soon clog.1.3.3 Reuse of domestic water9figure 1.3Major sources of water consumption in residential houses are the kitchen sink, the bath and/orshower, the basin in the bathroom and the toilet. While for obvious reasons the reuse of water fromthe toilet is not possible, the bathroom water, although contaiminated by soap and through laundry