Hydraulic ram pumps and Sling Pumps

OP-32-EAnnex 2: Example of tariff calculation for a piped system withtreatment (Metered graded rates)a) DescriptionA rural community in Colombia, is supplied with water and a Multi Stage Filtration System for thetreatment of water, which produces drinking water for 500 users, all of them with private taps. Thewater service is continuous and drinking water reaches the parameters required by the Colombian law.The community manages the system through a water committee, which hired one person of thecommunity with moderate educational level to manage the service. An operator and caretaker operateand maintain the system. The community, which is responsible for the most important decisions, electsthe water committee. The costs of the water supply system are assessed for 30 years, using a discountrate of 12%. The costs are as follows (in Colombian currency of 1996):Investment costs are the initial costs and include construction of infrastructure, land, equipment, prefeasibilitystudies and so on.Initial Investment Costs (IIC) (pesos 1996)Intake 170,905.00Sand Trap 4,533,619.00Raw Water Main 7,363,188.00River Crossings 8 6,414.00Sedimentation 16,435,600.00Upflow Roughing Filter 19,514,075.00Dynamic Roughing Filter 7,595,377.00Slow Sand Filter 59,071,822.00Drainage 893,653Water Storage Tank 26,766,841Distribution Network 37,748,853Water Storage Tank 2-3 7,500,000Sand Storage 7,000,000Design 7,000,000Metering 91,000,000TOTAL 292,600,347Recurrent costs include operation, maintenance and management costs.Operation and maintenance costs are related to the functioning of the technical components of thesystem, and include wages for the operator and caretaker, salaries for outside experts (for example toresand filters), payments for water quality analysis, materials for minor repairs, expenditure on inputs,etc.54