ADA Coastal Protection Works: Urgent Measures
The coastal town of Ada Foah, located 100km East of Accra, at the point where the Volta river flows into the Atlantic ocean, is experiencing severe coastal erosion of between of 4 – 7m/year. The local population and Ada village are under threat due to the eroding coastline. There has been a loss of land and infrastructure, with the resultant negative impact on agricultural potential and possible infrastructure development. The Government of Ghana has requested PMI in cooperation with International Marine and Dredging Company to design and manage the construction of a coastal defense system.

The Works
The main work items are the following:

• Investigations;
• Design;
• Physical Modeling;
• Construction;
• Management & Supervision

Investigations
Investigations to collect data have been done to validate and use as input for the design. The investigations included a topo- , bathymetric survey, through tide measurements, long term measurements and a study of the beach materials.

Design
The design consisted of the following:

• Wave Modeling;
• Hydrodynamic Modeling;
• Morphological modeling;

Physical Modeling
The hydrological stability of the design will be tested with a physical model. Two groynes will be constructed and tested with extreme waves and long periods. The design will be optimized during this phase.

Conclusion
The construction period is 24 months. The start of construction is scheduled for March 2011.

Management and Supervision
PMI is responsible for the management and supervision of the project during construction.