Upflow gravel filtration for multiple uses

The use of upflow gravel filtration (UFG) is relevant for water supply systems in rural areas and small towns in Colombia, because water quality from surface sources is changing due to the deterioration of watersheds caused by deforestation, erosion, and the discharge of untreated wastewater. These changes are intensified by the effects of global climate change. The main problems that occur include the increase in turbidity and suspended solid levels with higher peaks of longer duration. These changes affect the existing water treatment plants, causing higher operation and maintenance requirements and even interruptions in their operation. To overcome such problems a better understanding of the performance of UGF systems is needed because this type of pre-treatment is used in almost all low cost multi stage filtration systems in Colombia. This research combines analyses in existing full scale plants and research at lab and pilot filter scale in order to explore possible limitations, identify improvements and test other possible applications of the UGF technology. This includes the potential use with coagulation and flocculation to overcome longer periods of high loads of suspended solids; the application of a filter fabric on top of the UGF to reduce filter height and improve surface cleaning procedures; the application of UGF for iron and manganese removal from groundwater sources; and the potential use of UGF in micro-irrigation.