President of Peru Martín), and "Supreme Protector" (by Andrés de Santa Cruz). The following table contains a list of the individuals who have served as President of Peru. The Protectorate of Peru existed from August 3, 1821 until September 20, 1822. The Republic of Peru was declared on July 28, 1821 but it was constituted on September 20, 1822. It existed until August 11, 1836. In 1836, the south of the country declared itself independent by creating the Republic of South Peru, while the north of the country became the Republic of North Peru. The two states confederated with the Republic of Bolivia
Water resources management in Peru upper basins, whereas the southern part of the country is particularly prone to droughts. Aside from natural causes, such as El Niño Southern Oscillation, the effects of droughts and floods have been exacerbated by manmade interventions including soil erosion stemming from poor cropping and grazing practices, deforestation, and poor land use-practices. El Niño hits Peru approximately once every seven years and consists of heavy winds and rainfall associated with devastating floods and landslides. In 1997–1998 the costs of damages reached US$2 billion. Droughts severely affect the southern coast, producing agricultural losses as well as limitations on human water consumption. Preventive