Indonesia, an archipelago nation with over 13,558 islands and two-thirds of its area covered by water, relies heavily on its maritime infrastructure for economic development and energy distribution. Jetties and piers are crucial components of this infrastructure, particularly for the oil and gas sector, which remains the predominant energy source for its 270 million people. The continuous maintenance and construction of new jetty facilities are essential to improve supply reliability and meet the rising energy demand. However, jetty construction in Indonesia faces unique challenges, including environmental considerations, technical complexities, and project management risks.
The construction of jetties in Indonesia is a complex undertaking, driven by the nation’s archipelagic geography and its significant reliance on maritime transport for energy distribution. Key aspects include addressing persistent project cost and schedule overruns, ensuring accurate bids that reflect site-specific conditions, and mitigating environmental and social impacts. The process involves meticulous site assessment, design tailored to specific vessel types and environmental forces, and robust maintenance strategies to ensure longevity and operational efficiency.
The design and construction of jetties require careful consideration of various factors. Crucial design considerations include cost and budget, site assessment (water depth, wave and current conditions, geology), access and usability for various vessels, load calculations, environmental impact, construction methods, and maintenance and repair requirements. The typical construction process involves site selection and survey, design and planning, permitting (including environmental impact assessments), excavation and dredging, piling and foundation work, decking and superstructure, and the installation of accessories like lighting and signs.
Environmental and social impacts are significant concerns in jetty construction. Traditional jetty construction is resource and time-intensive and can adversely affect marine and terrestrial ecosystems and communities. The construction process generates substantial waste, including hazardous materials, and consumes significant amounts of fresh water. Furthermore, the production of construction materials like concrete and steel carries a high carbon footprint. For instance, building a 1000m jetty with 7m³ concrete depth can produce CO2 emissions equivalent to 7442 liters of diesel, and the steel production for such a jetty can equal the annual emissions of over 1,000 cars.
Dredging, a common activity to ensure sufficient water depth for vessels, disturbs the seafloor, increasing suspended sediment and turbidity, which can reduce wildlife habitat and alter water quality. Pile driving, another essential step, generates high sound pressure levels that can negatively impact marine biodiversity, including fish and marine mammals. The sound levels from pile driving can be extremely high, with impact pile driving of 14-inch steel H piles reaching 200dB, close to the marine mammal injury threshold of 220dB.
Beyond environmental concerns, jetties can also have significant community impacts. They can alter visual landscapes, affect traditional fishing and shipping areas, and contribute to coastal erosion due to their perpendicular positioning to the shore, which disturbs natural longshore drift. These impacts can reduce the resilience of natural storm protection features and potentially displace coastal communities.
To mitigate these challenges, “jettyless” infrastructure is emerging as an innovative alternative. This technology links ships to onshore terminals without fixed marine infrastructure, offering cost-effectiveness, reduced environmental impact, and greater flexibility. Jettyless solutions are designed to have a reduced life cycle cost, be modular and scalable, and operate in environmentally sensitive marine ecosystems with no impact on the seabed. They also significantly reduce visual and physical impact and can be adapted for various renewable energy sources.
Despite the complexities, advancements in construction methods and materials are continually being explored. For instance, the use of Fibre Reinforced Polymer (FRP) systems for retrofitting and strengthening existing concrete structures, including jetties, is gaining popularity due to FRP’s high strength-to-weight ratio, stiffness, corrosion resistance, and minimal alteration to structural geometry. Projects like the Lontar Extension Coal Fired Steampower Plant in Indonesia demonstrate detailed construction methodologies, including the use of barges, cranes, piling rigs, and specific materials like steel pipe piles and ready-mix concrete.
Risk identification and management are critical in jetty construction projects. Technical risks, such as soil conditions, water levels, weather, installation methods, and design changes, are often the most dominant. Non-technical risks include environmental, social, economic, legal, institutional, financial, and investment aspects. Common high-level risks identified in jetty projects include machine failure, delays in material procurement, incompatibility of implementation results with specifications, erratic weather, and inadequate shop drawings.
In summary, jetty construction in Indonesia is vital for its energy and economic landscape. While traditional methods present significant environmental, social, and technical challenges, the industry is moving towards more standardized project management practices, innovative “jettyless” solutions, and advanced construction materials and techniques to ensure sustainable and efficient development of its critical maritime infrastructure