 The authors estimate that the main reason is the massive expansion of access to water.According to Suez, the private concession in Buenos Aires extended access to water to 2 million people and access to sanitation to 1 million people, despite a freeze in tariffs imposed by the government in 2001 in violation of the concession agreement.The government argues that the concessionaire did not fully comply with its obligations concerning expansion and quality, saying that the supplied water had high levels of nitrate, pressure obligations were not kept and scheduled works were not carried out.