Even if one assumes 50 percent water distribution losses, Angat Dam can supply more than 20 million inhabitants, compared to a current population of 12 million. However, during severe droughts the water supply is insufficient. For example, during the drought of 1998 water supply to Metro Manila had to be reduced by 30 percent and water supply for irrigation was completely cut.Therefore, since the mid-1990s MWSS has pursued the construction of a new dam, the Laiban Dam, to supply Manila with water. Besides the need to hedge against the risk of drought, this is being justified with projected increased domestic per capita demand and projected increased commercial and industrial water demand. Civil society groups oppose the dam, saying that it is not needed, it would cause social and environmental damage and that MWSS is "obsessed" with the dam. The construction of the dam has been repeatedly delayed for lack of funding. Maynilad has begun to diversify its water sources by tapping into Laguna Lake, a large but polluted lake to the East of Manila. In February 2011, the President of the Philippines, Benigno Aquino, inaugurated the 0.1 million cubic meter per day multi-stage treatment plant, the first drinking water treatment plant to draw water from the lake. The plant will supply 1.2 million residents in the South of the metropolitan area. Manila Water also plans to tap into the lake to complement the water supply of the quickly growing Rizal area to the North. This is presented as a measure to adapt to climate change, since it will reduce the dependence on the Angat River which is vulnerable to drought. At the same time, together with NGOs Manila Water has planted trees covering more than 300 hectares of land in the Ipo and Marikina watersheds to protect its main current water source. Before privatization, the Metropolitan Waterworks and Sewerage System (MWSS) provided water for on average 16 hours every day to two thirds of Metro Manila. It was also inefficient, overstaffed and suffering from very high water losses. According to the Asian Development Bank, the amount of non-revenue water (NRW) (water supplied but not billable e.g. due to leakage and illegal connections) was more than 60 percent; this was much higher than in Seoul (35 percent), Kuala Lumpur (36 percent) and Bangkok (38 percent), and only comparable to Jakarta. Tariffs were low and MWSS was dependent on subsidies that the government was keen to abolish. The utility was saddled with debts of US$800 million owed to the Asian Development Bank, the World Bank and the Japan Bank for International Cooperation.