TRANSBOUNDARY AQUIFERS ALONG THE CANADA-US BORDER AND LINKS TO THE ISARM-AMERICAS REGIONAL STRATEGY

In Canada, water management is primarily a provincial responsibility. However, the federal government has responsibilities and may play a role when aquifers cross boundaries.

When an aquifer extends beneath the border of two jurisdictions, conflict may arise when one jurisdiction depletes groundwater resources that affect the quantity and quality of water available to the other jurisdiction. There is no competition in Canada for groundwater resources between provinces or with its southern neighbour. When needed, the equitable and “reasonable” use of shared waters is the most essential principle considered when negotiating a groundwater apportionment method. Other factors considered are: the priority use, the sustainable yield of the aquifer, and the joint apportionment of surface water and groundwater

The U.S.-Canada International Joint Commission (IJC) manages the international practices on transboundary waters in Canada. The IJC follows the 1909 Boundary Waters Treaty, providing the principles and mechanisms to help prevent and resolve disputes re to water. However, the 1909 Treaty did not mention groundwater; it was not until 1977 that transboundary aquifers were first considered by the IJC.

Since 2005, the Geological Survey of Canada has participated in the Internationally Shared Aquifer Resources Management (ISARM) initiative led by UNESCO. ISARM’s initiative is an effort to increase understanding of the management of transboundary aquifer systems (TAS) in the Americas. As a result, ten TAS between Canada and the USA were identified. The available information on the ten TAS was collected by the GSC and its American partners and summarized in three books published by UNESCO.

The GSC involvement in ISARM-Americas has facilitated and promoted international sharing of information and knowledge required for sustainable groundwater resources development and management between Canada and the U.S. This has resulted in a number of activities and products, the most recent of which will be presented in this topical session.

The presentation describes the links and the relevance of these studies to the UN Law of Transboundary Aquifers, and on how these might fit in the Strategy for the assessment and management of the American Transboundary Aquifer Systems, currently in preparation.