Consideration in choosing the appropriate flood control system for Tenggarong river

Abstract

Facts show that many developing countries are still struggling to face flood problems, including Indonesia. Flood does not only inundate lands and disrupt human activities, but also cause serious losses in many aspects. Tenggarong City, as a new developing city in East Kalimantan Province, has been recently suffering from serious inundation as consequence of high rainfall intensity, insufficient channel capacity, tidal backwater effect, and disintegrated land use management. The most frequently inundated area is identified located along the Tenggarong River including its tributaries, Saka Kanan River and Saka Kiri River. Based on the computation results obtained, it is shown that the Saka Kanan River and Tenggarong River have insufficient capacity to deliver the flood flow Even under return period of two years, those river reaches can generally only deliver half of the peak flood flow. Worse situation is indicated as Tenggarong River is strongly influenced by the tidal or when it must cope with the 25 years of flood flow. The height of inundation along the river varies from 2.73 m to 4.50 m above the bank elevation. Here, installing sheet pile or dike along the inundated area is indicated to be more effective to control the flood instead of channel normalization. Moreover, integrated land use management must be further considered for sustainable living.