Erosion and Accretion Index for Kuwaiti Coast

Abstract

Assessment of long term erosion and accretion rate of the coastal area is essential for selection<br />of different types of coastal structures. For example, it is not advisable to develop housing infrastructure on<br />the coast, which is historically eroding. Similarly it is not preferable to select an accreting site for the<br />construction of a port in order to avoid annual maintenance dredging after construction of the port. Kuwait is<br />a coastal country and hence it is essential to understand the long term coastal morphological changes of the<br />coast and identify the historically accreting or eroding or stable coast over a period of many years, say 10 to<br />15 years. The coastline evolution of Kuwait is investigated using Landsat remote sensing images (30 m<br />resolution) from 1989 to 2003, IRS-P5 images (2.5 m resolution) obtained for the year 2006-07 and 2003 aerial photos (0.38 m resolution). A total of 130 grids, each at a spacing of 1 nautical mile is used. The extent of accretion/erosion for 17 years (from 1989 to 2006) for the mainland coastline of Kuwait is assessed. The average shoreline change/year is calculated. Erosion and accretion index for each location is assigned based on the average annual erosion and accretion. From this study, it is found that annual erosion of more than 25 m does not exist in Kuwait. 1.54% of the coast has experienced annual erosion of 10 to 25 m and 0.77% of the coast has experienced 0 to 10 m annual erosion. 3.85% of the coast is stable. 43.85% of the coast has annual accretion of 0 to 10 m, 11.54% has annual accretion of 10 to 25 m and 38.46% has annual accretion of greater than 25 m. The complete details of this study are presented in this paper. The results will be useful for integrated management of Kuwaiti coast.