One guideline to sustainability defines three aspects of resources: non-renewable, renewable and waste disposal. This can be summarised as:
- the depletion of a non-renewable resource should require the development of a renewable substitute for that resource.
- the rate of harvesting renewable resources should not be greater than the rate at which new resources are regenerated;
- the amount of waste generated from a project should not be greater than the ability of the environment to assimilate the waste.
In short sustainability is the ability to use natural resources without completely using them up or destroying them, employing methods which are compatible with preserving them, and ensuring that what is built will last for a long time.
Dredging & sustainability
The World Organization of Dredging Association
(WODA) has adopted a series of principles that define the meaning of sustainable dredging. The principles emphasise that dredging helps to improve people’s quality of life and economic well-being by creating and maintaining essential water-based infrastructure. This includes:
- navigation dredging and land reclamation;
- enhancing environmental quality by beach nourishment;
- environmental (remediation) dredging to remove contaminated sediments;
- providing flood control;
- producing minerals and construction materials (sand); and
- supporting offshore energy production, including renewable energy.
By adhering to principles of sustainability for dredging and dredged material management using natural systems to integrate these actions, the dredging industry believes that the goals of environmental quality and economic prosperity can both be achieved.
WODA's objective is to achieve sustainable dredging through implementation of the following:
- From the start and throughout all stages of a dredging project, social, environmental and economic objectives should be considered and integrated.
- When developing a project design, parties should identify how to work with natural processes and recognize the site-specific characteristics of ecosystems as well as understand the carbon footprint of the dredging project.
- Project proponents, regulatory authorities and all stakeholders should be engaged at the earliest conceptual stage in the project’s development. Active collaboration is the key to achieving maximum social, environmental and economic benefits.
- Scientifically based criteria, performance guidelines and environmental safeguards for dredging and dredged material management should provide clear directions to project owners, planners and executing companies.
- Dredged material management should be based upon a holistic, systematic understanding of the ecosystem and natural processes at the project. Beneficial use of dredged materials should be given priority.
- Dredging can be a key solution for remediation and restoration at historically contaminated aquatic sites.
- Analysis of monitoring and assessment information before, during and after project implementation provides a basis for effective and sustainable project management.
The application of these principles will continue to help the dredging industry find sustainable solutions in the marine environment.