In term of inhabitants, Kota Tinggi population is increasing from 114,267 people in 1980 to 212,558 in 2005. It projected by year 2020, the population in this district will be increase nearly to 250,000 people. Alongside agriculture, tourism, mining, timber and industrial are among contributor to the economy of Kota Tinggi. Johor River and its tributaries are also important source of providing clean water not only for the Johor but also for the Singapore. To ensure adequate water supply, especially during drought season, there are three dams which were built in this basin namely as Linggiu dam, Lebam dam and Layang reservoir. The SRTM is a collaboration programme between National Aeronautics and Space administration (NASA) and National Geospatial-Intelligence Agency (NGA) of United States of America. River cross section survey enable sufficient coverage data for the area under water which may not be captured by others survey method such as radar wave and laser altimetry.