Development of predictive models for long and short term coastal changes
Coastal Zone Management
Along East and West Coast of India
To develop numerical model tool, for wave-coast-sediment interaction and to study
the influence of structure on coast.
To develop numerical model tool, for tide-coast interaction and to study the
influence of structures on coastal characteristics.
The numerical models would be validated with the field observations.
The interface between land and sea viz., the coastal region experiences variety of environmental conditions generated due to natural forces such as waves, tides, currents etc. These forces while interacting with sandy beaches result in wide range of phenomena such as generation of near shore currents, wave set up, wave set down, long shore currents, rip currents etc. These forces also induce change in beach profile characteristics depending on the sediment characteristics and on the beach slope variations. The nature of interaction between these forces and the near shore region is quite complex due to the reasons that the interaction between the forcing functions and the sediments have not been understood clearly. In addition, the type of coastal features also contributed to the complexity of the problems, for example, rocky coasts may exhibit totally a different scenario under the given environmental condition where as sandy coast would present a different picture.
Numerous structures are constructed along the coast for various reasons. Of all the types of structures, harbors, jetties, sea halls, groins, marine outfalls, etc. have certain impact on the neighboring coast under the water body also respond to the change in environmental conditions. The problem becomes acute when the coastal structures are associated with sediment movement in addition to other forcing functions. Simulating thesis conditions in a laboratory is difficult and even if an attempt is made the results may be qualitative in nature. Under these conditions numerical methods are valuable in order to derive solution with reasonable accuracy.
The present project aims at developing software’s capable of predicting the past coastal characteristics based on historic data on a) wave climate, wind conditions etc, and b) the coastal structures that were responsible for the change in the scenario. In addition, the model would be capable of forecasting events that would occur due to proposed development activities along the shoreline with present day configuration and environmental characteristics. The numerical model would consider 1) wave coastal line interaction 2) tide coastal line interaction and provide the necessary numerical tool for the decision maker’s in regard to planning and development of coastal features.
Highlights / Findings:
The model is capable of predicting the change in the coastal characteristics due to natural and man-made interference.
Data pertaining to East Coast of India on the following parameters are adopted for modeling
Prediction of coastline advance in the presence of a structure. Figure1 & Figure2
show the development of the shoreline with respect to time.
Beach profile development under the natural circumstances. Figure3 shows the
Date of project completion:
12th April 2005
Total cost of Project:
Rs. 9.42 lakhs
Prof. J. S. Mani
Department of Ocean Engineering
Indian Institute of Technology Madras
Chennai - 600036
Phone: 0091 - 44 – 2257 8634
Fax: 0091 - 44 – 2257 0545