A Study of Vessel Traffic Risk Management in Mombasa Approach Channel

Abstract

Mombasa is the second largest city in Kenya located on the east coast of Kenya. Mombasa is famous for its beautiful natural white sand beach, aquatic life, rich cultural and historical wealth. In this city is the port of Mombasa which is the largest port in East Africa and is the gateway to East and Central Africa and plays a very important role in facilitating trade and development of the region. The port has strategic importance far beyond the borders of Kenya. As the largest port in East Africa, it is the main gateway for the import and export of goods not only for Kenya but also to landlocked countries of the East African Community, the Democratic Republic of Congo, southern Sudan, and southern Ethiopia. However being among the top five largest ports in Africa, navigating in Mombasa approach channel is a challenge due to its oceanographic structure. Vessel heading into or out of Mombasa port has to maneuver through two major bends and change the heading three times. Local ferries operating at Likoni channel also pose as potential navigation risk on transit vessels with an average of 196 daily crossings. Navigation risk of the ferries is compounded by narrow, 500m wide, waterway at Likoni channel and shallow coral reefs and sand banks at the entrance to the inner channel. In this thesis paper, the main aim is to improve marine traffic safety by carrying out a risk assessment and proposing countermeasure in Mombasa approach channel using vessel traffic risk management technique; and to investigate navigation risk of local ferry traffic on transit traffic on Mombasa approach channel. The target research area is the fairway area stretching from fairway buoy number 1 to buoy number 10. ~ ix ~ The main aim is achieved by carrying out marine traffic survey to determine marine traffic characteristics such as traffic volume and traffic flow of vessel traffic after which, risk assessment on Mombasa approach channel is carried out using three marine traffic risk assessment models namely; Environmental Stress Model, PARK model and IWRAP model and thereafter risk mitigation countermeasures are proposed in this study. Quantitative risk assessment by ES model, PARK model and IWRAP model showed that there is a high risk of crossing collision between local traffic and transit traffic at crossing region where ferry operate; total groundings in Mombasa and Ulsan waterway are equal; powered grounding frequency in Mombasa is almost twice that of Ulsan. Risk assessment results showed that there is a need to come up with traffic management measures/policies that will mitigate the risk of collision and running aground of vessels thereby improving marine traffic safety. Traffic control of ferries, setting up a Local Traffic Service (LTS), VTS report line due to crossing ferry and proper layout of AtoN were proposed as countermeasures. A study of the countermeasures showed that; traffic control of the local traffic is effective in reducing collision risk at Likoni channel; Local Traffic Service will improve marine traffic safety by reducing workload on the Mombasa VTS; The reporting line will providing the reference point on when to instruct the ferries to stop crossing thereby increasing marine traffic efficiency and safety; Re-organization of lateral buoys will increase relative position and navigation accuracy when the vessel is navigating in Mombasa approach channel so as to avert the danger of vessel running aground. From the above observations and results from analysis, this thesis recommends the proposed countermeasures to be applied on the Mombasa approach channel so at to improve marine traffic safety.