Genoa's Grand Plans are Dredging Success Story
Italy's Port of Genoa faced a range urban planning and environmental protection challenges during land reclamation works for construction of two new container terminals over the last 10 years. Tony Tran spoke to Marco Vaccari, Portfolio & Project Manager in the Technical Department of the Genoa Port Authority to find how they were overcome:
Tell us about the Port of Genoa.
The Port of Genoa is one of the major Italian seaports in the Mediterranean sea. With a trade volume of 50 million tons and two million TEUs, it is the busiest port of Italy by cargo tonnage. Genoa Port covers an area of about 700 hectares of land stretching along the coastline, with 47 kilometers (29 miles) of maritime ways and 30 kilometers (19 miles) of operative quays. Here container terminals cohabit with cruise, ro-ro, chemical and oil terminals. Drydocks and industrial area have to share the space with the marina and the airport. As the Port and the city coexist naturally on the same stretch of coast, a large part of the working port coastline shares the function of urban waterfront.
Genoa Port has been subject of uninterrupted development since 2001 with two grand master plans. What are their goals?
The first Port Master Plan was approved in 2001 based on the new Italian Law 84/94, where Port Authorities would assume new functions and primary roles in planning and infrastructure development in close collaboration and dialogue with the municipality and regional government. In this context, the Genoa Master Plan has foreseen the construction of two new container terminals in the commercial areas: Calata Bettolo and Ronco Canepa.
Calata Bettolo is located in the Eastern part of the commercial area and is characterized by a total area of about 300,000 square meters, a 750-meter-long (2,460-foot-long) berth and water depth of 17 meters (56 feet). The project involved dredging of about 2,500,000 cubic meters of sand and rock and land reclamation of approximately 180,000 square meters. Works started in 2007, and today they are completed.
Ronco Canepa located in the western part of the commercial area and is characterized by a total area of about 170,000 square meters, a 640-meter-long (2,100-foot-long) berth and water depth of 15 meters (49 feet). The project involved river mouth maintenance dredging of about 1,000,000 cubic meters of mainly sand and land reclamation of about 65,000 square meters. Works had started in 2009 and is on-going.
The most recent Port Master Plan, developed in 2015, is a bold response to the need to identify a new model for port development, in collaboration with local government and other public and private stakeholders, aimed at improving relations between the port and the city, which in Genoa live side by side.
What challenges did the 2001 Genoa Port Master Plan invoke?
As a matter of fact, the two different projects (Calata Bettolo and Ronco Canepa) faced the same challenges and constraints with regards to dredging and land reclamation issues. These challenges have been managed throughout all project phases, from planning and design phase until delivery.
Challenges were first connected to the port’s positioning, due to its intimate proximity with the city. Being adjacent to the airport also imposes severe constraints during construction phases. The Genoa port also poses a complex reality, due to the different commercial interests and multiple operators and stakeholders.
Firstly, it was necessary to guarantee port and terminal operations along the entrance and the main channel during the construction phases. Therefore, dredging activity was regulated in close connection with harbormasters when determining the availability of areas to dredge. This constraint had to be managed in advance, both across the detailed design and within the contract, so as to avoid claims from the General Contractor.
The variety of areas and materials to dredge also meant the employment of different types of dredging equipment, which had to be analyzed in advance. From for the environmental point of view, the Italian law on dredging and land reclamation (D. Lgs. N° 152/06) was very strict, making related works time-consuming. It was necessary to implement chemical analyses and characterization in advance for the entire port seabed in order to avoid dredging disruption and claims from the General Contractor.
In addition, due to proximity to the urban waterfront, during dredging operations it was necessary to maintain constant control of turbidity levels and find the best trade-off with marine equipment.
Finally dredging had to be performed in compliance with structural stability of existing structures, so the detailed design imposed restrictions on the depth and distance from existing quays and berths.
The dredging was for maintenance purpose in both cases. In the Calata Bettolo project, dredging all along the channel and quays allowed the Port to accept bigger vessels, whereas in Ronco Canepa, dredging along the river estuary was beneficial to river safety conditions, reducing flooding risk upstream.
Last but not least, it was necessary to adhere to funding and time schedule constraints.
Land reclamation at Ronco Canepa.
What have been the outcomes of the projects and lessons learned?
There have been some important benefits arising from the projects. The construction of the container terminals using dredged materials instead of quarry materials has been a money-saving but time-consuming solution. 3,500,000 cubic meters of dredged material would otherwise have had to be discharged in an authorized landfill, and this procedure would have been very expensive.
We achieved a social benefit too, as the works were performed at sea with state-of-the-art marine equipment and dredgers. This meant that any potential environmental impact related to dust or traffic from the operations did not affect the waterfront and the city.
However, there were disadvantages. The combination of risk mitigation solutions connected with dredging operations and time-consuming activities on consolidation of the dredged materials (compared to the employment of quarry materials otherwise) increased the time required for the projects delivery.
Due to large volume of dredging material and the strict environmental requirements of Italian Law, technical constraints had to be faced and managed during the delivering phase of the terminals. The bottom line is that the employment of dredged materials for the realization of terminals could lead to significant cost savings, but it also leads to much longer delivering times. Ship construction evolves much faster than port infrastructure, and terminal requirements for vessel dimensions have changed dramatically over the last 10 years. To overcome this challenge, it was beneficial to overestimate vessel dimension (draft, width and LOA) at the design phase.
This article is a reflection of a presentation delivered by Marco Vaccari, Portfolio & Project Manager, Genoa Port Authority, at the 7th Dredging & Land Reclamation Asia Summit 2017 organized by Equip Global, Singapore.
The opinions expressed herein are the author's and not necessarily those of The Maritime Executive.