The lakes and reservoirs (man-made lakes) of Malaysia, interlinked with various inflowing and outflowing rivers, constitute an important component of its water resource system, contributing to the socio-economic transformation of the country.　Only few lakes in Malaysia are of natural origin, mostly formed as part of swamp wetlands. Lake Chini and Lake Bera located in the Pahang River Basin are among them.   Lake Bera, a wetland of international importance, was accepted as Malaysia's first RAMSAR site in 1995.  There are no less than73 man-made lakes created for water supply, irrigation hydropower generation, flood mitigation, and others.    Pollution from nutrients and sediment that drain into them from their catchments, however, is becoming a serious threat to all Malaysian lakes, causing deterioration of water quality to varying degrees. Excessive growth of algae or macrophytes caused by eutrophication is widespread.