Land-Based Sources of Marine Pollution

The United Nations estimates  offsite linkthat as much as eighty percent of all global marine pollution originates from land-based sources, threatening marine life in general, but especially coastal waters and areas of high biological productivity. Pollutants of land-based origin offsite link include pesticides, chemical waste, cleaning agents, petroleum products, mining waste, garbage and sewage. Even pharmaceuticals ingested by humans, but not fully processed by the human body, have been detected in fish.  Nitrogen-based fertilizers which are routinely used in agricultural operations migrate to rivers and estuaries and ultimately to the sea where they promote harmful algal growth and deprive ocean areas of oxygen, creating multiple dead zones offsite link in which marine life cannot exist. Floating plastic waste, bags, packaging foam, and other solid waste materials are often consumed by marine mammals and birds, sometimes with fatal effects.  Ocean currents in certain areas tend to collect such debris into large floating garbage patches. The Pacific Trash Vortex offsite link, which is approximately the size of Texas, is one such patch. There can be no doubt that waste and debris that originates from onshore human activities has the potential to greatly impact the marine environment and its resources.  The way to address the problem globally has not always been clear.  

International efforts to comprehensively regulate land-based sources of marine pollution encounter obvious difficulties at the outset. These include considerations of state sovereignty offsite link and the right of a state to pursue its own economic and social development. The sources of land-based marine pollution are invariably within national jurisdictions, and states are understandably reluctant to agree to legally-binding instruments that can have the effect of restricting their economic development. 

The 1982 Law of the Sea Convention offsite link (UNCLOS) prescribes certain obligations with respect to land-based sources of pollution, but they are of such a general nature as to be largely ineffective on their own.

  • UNCLOS Article 194 directs states to take all measures that are necessary to prevent, reduce and control pollution of the marine environment from any source and to ensure that any pollution arising from activities under their jurisdiction and control does not spread beyond areas in which they exercise sovereign rights. 
  • Article 207 calls upon states to adopt laws and regulations to prevent, reduce and control pollution of the marine environment from land-based sources, including pollution that reaches the marine environment by means of rivers, estuaries, pipelines, and outfall structures, “taking into account” internationally agreed rules, standards and recommended practices and procedures.  States shall endeavor to harmonize their policies at the appropriate regional level.
  • Article 213 calls upon states to not only enforce their laws and regulations adopted in accordance with Article 207, but to adopt laws and regulations and take such other measures necessary to implement applicable international rules and standards to prevent, reduce and control pollution of the marine environment from land-based sources.

One commentator offsite link noted that the obligations imposed by UNCLOS to prevent pollution from land-based sources are weaker than obligations relating to pollution from other activities, such as seabed activities subject to national jurisdiction (Art. 208), dumping (Art. 210), and pollution from vessels (Art. 211). States are merely called upon to “take into account” international standards and practices. Each state is thus left to judge what measures should be adopted and whether they should be more or less stringent than those reflected in international standards and practices.

Pioneering Regional Agreements  Where there has been success in addressing land-based sources of marine pollution, it tended to be on the regional level. Regulation of land-based sources is significantly more complex than controlling pollution from vessels.  It involves a greater variety of substances which derive from a wide variety of activities. Because regulating these substances and activities can impact a state’s industrial and economic development, states will seek assurances that any legally-binding arrangement will not adversely affect their national interests. Regional agreements can be more easily tailored to such considerations. They can also better account for differences in ocean environment and ecology.  Pioneering legal instruments in this area included:

Montreal Guidelines  An ad hoc working groups established by the United Nations Environment Program (UNEP) met between 1983 and 1985 and, drawing on common elements and principles in existing agreements and on experience gained in their implementation, produced the Montreal Guidelines for the Protection of the Marine Environment Against Pollution from  Land-Based Sources offsite link. The Guidelines are of a “recommendatory nature” and intended to provide a broad framework for the development of bilateral, regional and multilateral agreements for the protection of the marine environment against pollution from land-based sources.

Agenda 21  One of the major accomplishments of the U.N. Conference on Environment and Development offsite link, which was held in Rio de Janeiro in 1992, was the release of “Agenda 21 offsite link” – a comprehensive plan of action to, among other things, achieve sustainable use of global and regional resources associated with the atmosphere, oceans and marine organisms.  

  • Chapter 17 of Agenda 21 offsite link focuses on the “[p]rotection of the oceans, all kinds of seas, including enclosed and semi-enclosed seas, and coastal areas and the protection, rational use and development of their living resources.”  
  • Among the seven program areas in Chapter 17, Programme Area B addressed the subject of “Marine environmental protection,” stressing the need for a “precautionary and anticipatory rather than a reactive approach.”  
  • In carrying out a commitment to address the degradation of the marine environment from land-based activities, states were called upon to take action at the national level and, where appropriate, at the regional and sub-regional levels, taking into account the Montreal Guidelines. Agenda 21, ¶ 17.24.   
  • In addition, the UNEP Governing Council was invited to convene, as soon as practicable, an intergovernmental meeting on the protection of the marine environment from land-based activities.  Agenda 21, ¶ 17.26.

That intergovernmental meeting was held in Washington, D.C. from October 23 to November 3, 1995, with 108 states and the European Commission in attendance. It produced two documents: (a) the Washington Declaration on the Protection of the Marine Environment from Land-Based Activities offsite link, which focused on nine specific subject areas, and (b) the Global Programme of Action for the Protection of the Marine Environment from Land-Based Activities (the GPA).

Regional Seas Policy and Frameworks  UNEP’s Regional Seas Programme  offsite link(RSP) seeks to address the degradation of the world’s oceans and coastal areas by engaging neighboring countries – countries that are in proximity to one another – to undertake both comprehensive and specific actions to protect their shared marine environment.  Pollution from land-based activities has become a key issue for RSPs.  Among the “first generation” instruments – following on the examples of the Paris and Helsinki Conventions – were the UNEP 1980 Protocol for the Protection of the Mediterranean Sea Against Pollution from Land-Based Sources and Activities, offsite link the Protocol for the Protection of the South-East Pacific Against Pollution from Land-Based Sources offsite link, and the Kuwait Protocol for the Protection of the Marine Environment Against Pollution from Land-Based Sources offsite link.

The Regional Seas programmes function through Action Plans  offsite linkwhich are adopted by member governments. An Action Plan provides the substance of the programme and the outline of a strategy, based on the region's particular environmental challenges as well as its socio-economic and political situation.  In most cases, Action Plans have as their foundation a strong legal framework reflected in a regional Convention offsite link that is linked to associated Protocols which address specific problems. 

In bringing together governments, the scientific community, intergovernmental organizations, and other stakeholders, the various Regional Seas Conventions and Action Plans provide valuable regional frameworks for assessing the state of the marine environment; for addressing key developments such as socio-economic activities, coastal settlements, and land-based activities  offsite linkthat interact with the marine environment; and for agreeing on appropriate responses in terms of strategies, policies, management tools and protocols. 
There are currently 18 regional seas programmes  offsite linkwith a total membership of approximately 140 countries. Fourteen of these have adopted legally-binding conventions. 

Further Reading

Last updated February 9, 2018