Prior to Klong Saeng being designated a wildlife sanctuary, parts of the area were settled by humans with more than 40 villages inside what is now the sanctuary boundary. All of these villages were relocated after the area was designated as a wildlife sanctuary in 1974. From 1986-1988 a major dam was constructed near the sanctuary’s southern boundary to make a large reservoir that now extends through the central portion of the protected area. The approximate total land area of the sanctuary is 1,155 km2 with the surface area of the reservoir approximately 81 km2. Although commercial activities are usually prohibited within wildlife sanctuaries, a range of activities are permitted within Klong Saeng including commercial fishing and a tourism industry revolving around floating rafts at approximately 10 locations around the reservoir.