other atoll islands of a similar size, Fongafale does not have a thick freshwater lens. The narrow fresh water and brackish water sheets in the sub-surface of Fongafale islet results in the taro swamps and the fresh groundwater resources of the islet being highly vulnerable to salinization resulting from the rising sea-level. In addition to the increased risk of salinized by the sea-level rise, the freshwater lens is at risk from over extraction due to the large population that now occupies Fongafale islet; the increased extraction can be exacerbated by a decrease of the rainfall recharge rate associated with the climate change. Water pollution is also a chronic problem, with domestic wastewater identified as the primary pollution source. Approximately 92% of households on Fongafale islet have access to septic tanks and pit toilets. However these sanitary facilities are not built as per the design specifications or they are not suitable for the geophysical characteristics, which results in seepage into the fresh water lens and run off into coastal waters. On Funafuti and on the other islands, rainwater collected off the corrugated iron roofs of buildings is now the primary source of fresh water. On Funafuti a desalination unit that was donated by Japan in 2006 also provides fresh water. In response to the 2011 drought, Japan funded the purchase of a 100 m³/d desalination plant and two portable 10 m³/d plants as part of its Pacific Environment Community (PEC) program. Aid programs from the European Union and Australia also provided water tanks as part of the longer-term solution for the storage of available fresh water. Aquifer salinization and the impact on Pulaka production Swamp taro (Cyrtosperma merkusii), known in Tuvalu as Pulaka, is grown in large pits of composted soil below the water table, Pulaka has been the main source for carbohydrates, it is similar to taro, but "with bigger leaves and larger, coarser roots". In recent years the Tuvaluan community have raised concerns over increased salinity of the groundwater in pits that are used to cultivate pulaka. Pits on all islands of Tuvalu (except Niulakita) were surveyed in 2006. Nukulaelae and Niutao each had one pit area in which salinity concentrations thought to be too high for successful swamp taro growth. However, on Fongafale in Funafuti all pits surveyed were either too saline or very marginal for swamp taro production, although a more salt tolerant species of taro (Colocasia