Suriname is located on the north-east coast of South America (appr. 54o-58o WL and 2o-6o NL) and has an area of about 156,000 km2. The climate is tropical, with daily temperatures varying between 23 and 31 degrees Celsius (ºC). The relative humidity is about 80% a year, the sunshine is about 58% a year (1931-1960). The average annual rainfall in Paramaribo is about 2,200 millimeters. In the whole country, the rainfall varies from less than 1,750 to greater than 3,000 millimeters annually. The annual evaporation is about 1,700 mm (1931-1960). About 67% of the precipitated water on the Suriname rivers basins returns to the atmosphere by evapotranspiration and approximately 33% is drained off into the Atlantic ocean. The year can be roughly divided in two wet seasons (April to mid-August and December to February) and two dry seasons (February to April and mid-August to December). According to the Water Poverty Index (WPI), Suriname belongs to the top 10 water-rich nations in the world are (World Water Council, 3rd World Water Forum, 2002).