11.3 Mission III : Coastal and Environmental Engineering

The activities under this mission are concentrated on developing numerical models for various coastal processes, including pollution dispersion, benchmarking them against international software and applying them practically for various coastal projects under implementation.

Numerical models for various coastal processes:

Finite element based numerical models for near shore wave dynamics, accounting for wave refraction, shoaling difraction, sea bed friction and wave breaking have been developed. A `Storm surge prediction' model, based on finite element techniques having better capabilities compared to conventional `Finite difference model' has been developed in NIOT. All these models have been benchmarked with internationally renowned software of MIKE 21 series. Now these models are being applied to practical cases along Indian coasts.

The various numerical models on near shore wave dynamics were used for Coastal Engineering applications in the design of breakwaters for many new harbour projects. Recent examples are fishing harbour at Thottapally, Kerala, landing jetty at Amini Island of Lakshadweep and wharfs at Hut Bay and Campbell Bay of Andaman islands.

As an extension to the storm surge prediction model, an `inundation prediction' model was developed by incorporating the actual near shore bathymetry and coastal topography. To apply this model for the specific cyclone prone area of Andhra coast between Nellore and Machilipatnam, the close grid topography at 0.5m intervals has been integrated with the model. Validation of the model for the cyclone data of the past is in progress.

Coastal Environment:

The major activity of NIOT in this area relates to `Development of EIA guidelines for marine developmental activities' and `Determination of waste load allocation for specific coastal creeks/ estuaries', as a contribution to the Integrated Coastal and Marine Area Management (ICMAM) programme of DOD, being implemented by its Project Directorate at Chennai. As a part of this activity, a status report of EIAs in the country and international EIA guidelines was prepared and submitted to ICMAM directorate in Chennai. Ennore creek has been taken up as the first site for `Waste load allocation' studies and extensive base line data collected which will be used for developing the use classification as well as for water quality modelling in the creek.

This group has also completed numerical simulations of the thermal pollution from the 2000 MW thermal power plant, being proposed by NTPC at Simhadri, Visakhapatnam. This study identified the right locations for the sea water intake and the effluent discharge points. A similar study was carried out for Hinduja National Power company for its proposed plant near Visakhapatnam.