Mapping of Pollution Load Capacity of Tidal Manggar Watershed, Balikpapan City

Abstract

The Tidal River Manggar system is mostly (± 75%) still in the form of forest and about 25% is land that has been exploited / developing land. Manggar River is influenced by the tides of sea water making the characteristics of brackish water with thick mangrove trees. The purpose of this research is to know the characteristics of tidal water quality and calculate the pollution load value of Manggar River by using GIS mapping. Water sampling was divided 10 segments of the river and then analyzed the laboratory. Calculation of river basflow was using Thornwhite approach. The influence of sea water and mangrove estuaries has become more dominant in the formation of river water quality characteristics, especially in the dry season. The sea water entering the river brings minerals from both the sea and the mainland into a trap that causes the Manggar River to become rich in nutrients and river biota. Regulations in Indonesia have not specifically regulated brackish water quality. High BOD and COD values can not be categorized as polluted by law standard, because the source of pollutants is a natural material, where this condition is a balance of mangrove ecosystem. The pollutant source of the Manggar River originates from the Sub-Basin which contributes to pollution loads whose value depends on the discharge of each sub-catchment.