Yes – Correct

Where appropriate, States are obligated to protect the ecosystem of an international watercourse.

Article 20 of the UN Watercourses Convention provides that ‘Watercourse States shall, individually and, where appropriate, jointly, protect and preserve the ecosystems of international watercourses’. The obligation to protect ecosystems encompasses measures relating to conservation, security and water-related disease, as well as technical and hydrological control mechanisms, such as the regulation of flow, floods, pollution, erosion, drought and saline intrusion. Additionally, the obligation to protect includes the duty to shield ecosystems from a significant threat of harm and therefore the need to adopt a precautionary approach.

It should be noted though that such decisions must be weighed against all relevant factors applicable to the principle of equitable and reasonable utilisation, as well as the duty of no significant harm.

For further discussion on the duty to protect the ecosystems of an international watercourse, see Fact Sheet #7.

No – Incorrect

Where appropriate, states are obligated to protect the ecosystem of an international watercourse.

Article 20 of the UN Watercourses Convention provides that ‘Watercourse States shall, individually and, where appropriate, jointly, protect and preserve the ecosystems of international watercourses’. This obligation to protect and preserve ecosystems is seen as an extension of the requirement that States utilise their waters in an equitable and reasonable manner.

The “ecosystem” concept was used by the International Law Commission (ILC) when they drafted the text of the Convention because it was seen to have a narrower scope to that of the “environment”.  “Ecosystem” was accordingly defined by the ILC as “an ecological unit consisting of living and non-living components that are interdependent and function as a community”. In other words, it can be said that any activity that threatens the protection and preservation of ecosystems of an international watercourse might potentially be considered inequitable and unreasonable because it threatens the long-term viability of the resource.

The obligation to protect ecosystems also encompasses measures relating to conservation, security and water-related disease, as well as technical and hydrological control mechanisms, such as the regulation of flow, floods, pollution, erosion, drought and saline intrusion. Additionally, the obligation to protect includes the duty to shield ecosystems from a significant threat of harm and therefore by the need to adopt a precautionary approach.

The obligation to preserve ecosystems of international watercourses refers to maintaining freshwater ecosystems in a “pristine or unspoiled condition” and can be seen as subordinate to the obligation to protect. Sometimes the preservation of watercourse ecosystems involves setting aside of a portion or the entirety of a river flow based on its condition or beauty.

It should be noted though that such decisions must be weighed against all relevant factors applicable to the principle of equitable and reasonable utilisation, as well as the duty of no significant harm.

For further discussion on the duty to protect the ecosystems of an international watercourse, see Fact Sheet #7.

Yes – Correct

States are obliged to prevent, reduce and control pollution which may cause significant harm to an international watercourse, even if no actual significant harm has already occurred to another State.

Under Art 21(2) of the UN Watercourses Convention, ‘Watercourse States shall, individually and, where appropriate, jointly, prevent, reduce and control the pollution of an international watercourse that may cause significant harm to other watercourse States or to their environment, including harm to human health or safety, to the use of the waters for any beneficial purpose or to the living resources of the watercourse’. Hence, States are subsequently required (within their own territorial boundaries) to prevent new sources of pollution as well as reduce and control existing sources of pollution that may potentially cause significant harm to another State via a shared international watercourse.

The use of the term ‘may’ is particularly significant in so far as the approach is based on the Precautionary Principle in sustainable development theory and practice.

The due diligence component of the obligation not to cause significant harm codified in Article 7 of the Convention must not be forgotten in order to ensure consistency between Article 7, Article 20 and any other provisions in so far as they relate to the duty regarding prevention, reduction and control of “pollution of an international watercourse that may cause significant harm to other watercourse States or to their environment” in Article 21 of the Convention.

For further discussion on the obligation under the Convention to prevent pollution, see Fact Sheet #5 and Fact Sheet #7.

No – Incorrect

States are obliged to prevent, reduce and control pollution which may cause significant harm to an international watercourse, even if no actual significant harm has already occurred to another state.

Under Art 21(2) of the UN Watercourses Convention, ‘Watercourse States shall, individually and, where appropriate, jointly, prevent, reduce and control the pollution of an international watercourse that may cause significant harm to other watercourse States or to their environment, including harm to human health or safety, to the use of the waters for any beneficial purpose or to the living resources of the watercourse’. Hence, states are subsequently required (within their own territorial boundaries) to prevent new sources of pollution as well as reduce and control existing sources of pollution that may potentially cause significant harm to another state via a shared international watercourse.

The use of the term ‘may’ is particularly significant in so far as the approach is based on the Precautionary Principle in sustainable development theory and practice. In such instances, scientifically plausible but still undetermined risks of any detrimental effects to the environment and human health/ safety should outweigh the need to commence or continue with the potential source of such risks in the decision-making process. Adopting precautionary approach in this context would mean that planned measures by a Watercourse State which may cause pollution to an international watercourse that could reasonably pose a risk of significant harm to the environment or human health and safety must be examined further so as to assess and, where possible, mitigate such risks prior to approving or commencing the planned measures.

Art 21(1) of the Convention defines “pollution of an international watercourse” as meaning “any detrimental alteration in the composition or quality of the waters of an international watercourse which results directly or indirectly from human conduct”. Whilst acknowledging that the scope of “pollution” within this provision therefore includes “any detrimental alteration”, the Online User’s Guide points out that based on the reference to significant harm in Art 21(1):

Certain harm, even leading to significant pollution, may therefore be tolerated if the polluting watercourse state is making its best efforts to reduce the pollution to a mutually acceptable level. The rationale behind such a condition, is to prevent ‘undue hardship’ or inequitable results, whereby the detriment to the watercourse state experiencing harm is ‘grossly disproportionate’ to the benefit gained by the polluting watercourse state.

The due diligence component of the obligation not to cause significant harm codified in Article 7 of the Convention must not be forgotten in order to ensure consistency between Article 7, Article 20 and any other provisions in so far as they relate to the duty regarding prevention, reduction and control of “pollution of an international watercourse that may cause significant harm to other watercourse states or to their environment” in Article 21 of the Convention.

For further discussion on the obligation under the Convention to prevent pollution, see Fact Sheet #5 and Fact Sheet #7.

Yes – Incorrect

Upon the request of another Watercourse State, a co-riparian state must enter into consultations concerning the management of an international watercourse, yet there is no obligation to establish joint management mechanisms; it is simply recommended as an option to assist co-riparian states.

Art 24(1) of the UN Watercourses Convention stipulates that: ‘watercourse states shall, at the request of any of them, enter into consultations concerning the management of an international watercourse, which may include the establishment of a joint management mechanism’. Hence, States are required upon request to consult with other co-riparians regarding the management of a shared international watercourse. However, these or any other co-riparian States sharing the same international watercourse are not obligated to establish joint management mechanisms. Rather joint management mechanisms are offered as an option in order to assist States in achieving the effective management of an international watercourse. Importantly, ‘management’ in this context is defined under Art 24(2) of the Convention as specifically referring to: ‘(a) planning the sustainable development of an international watercourse and providing for the implementation of any plans adopted; and (b) otherwise promoting the rational and optimal utilisation, protection and control of the watercourse’.

For discussion on joint management of an international watercourse, see generally Fact Sheet #11.

No – Correct

Upon the request of another Watercourse State, a co-riparian State must enter into consultations concerning the management of an international watercourse, yet there is no obligation to establish joint management mechanisms; it is simply recommended as an option to assist co-riparian States.

Art 24(1) of the UN Watercourses Convention stipulates that: ‘watercourse states shall, at the request of any of them, enter into consultations concerning the management of an international watercourse, which may include the establishment of a joint management mechanism’. Hence, States are required upon request to consult with another co-riparian regarding the management of a shared international watercourse. However, these or any other co-riparian States sharing the same international watercourse are not obligated to establish joint management mechanisms. Rather joint management mechanisms are offered as an option in order to assist States in achieving the effective management of an international watercourse.

For discussion on joint management of an international watercourse, see generally Fact Sheet #11.

Yes – Correct

Watercourse States are each under an obligation to maintain and protect installations from damage within their own territories, to the extent that this duty is carried out to the best of their abilities.

Art 26(1) of the UN Watercourses Convention provides that ‘watercourse states shall, within their respective territories, employ their best efforts to maintain and protect installations, facilities and other works related to an international watercourse’. On this basis, there is a definite obligation imposed upon watercourse states to maintain and protect any installations that are situated on a shared international watercourse within their own territorial borders from damage.

However, this requirement to protect and maintain installations subsequently has a limitation imposed on it by the phrase in Art 26(1) for States to ‘employ their best efforts’. This limits the obligation under Art 26(1) to scenarios concerning damage to, or maintenance of an installation that are reasonably within the capacity of each Watercourse State respectively to address or avoid.

For further discussion on similar obligations relevant to planned measures, see Fact Sheet #6.

No – Incorrect

Watercourse States are each under an obligation to maintain and protect installations from damage within their own territories, to the extent that this duty is carried out to the best of their abilities.

Art 26(1) of the UN Watercourses Convention provides that ‘watercourse states shall, within their respective territories, employ their best efforts to maintain and protect installations, facilities and other works related to an international watercourse’. On this basis, there is a definite obligation imposed upon watercourse states to maintain and protect any installations from damage that are situated on a shared international watercourse within their own territorial borders.

However, this requirement to protect and maintain installations subsequently has a limitation imposed on it by the phrase in Art 26(1) for States to ‘employ their best efforts’. This limits the obligation under Art 26(1) to scenarios concerning damage to, or maintenance of an installation that are reasonably within the capacity of each watercourse state respectively to address or avoid. The provision therefore caters for differences in capacity between co-riparian states whilst still holding each to a common duty in protecting and maintaining any installations as much as is reasonably possible given the capacity of the respective watercourse states.

Finally, the question of whether or not a watercourse state has fulfilled its limited obligation to protect and maintain installations also incorporates a due diligence requirement whereby each state must demonstrate that it took reasonable steps (based on its capacity) in order to achieve this outcome.

For further discussion on similar obligations relevant to planned measures, see Fact Sheet #6.

Yes – Correct

Pursuant to Article 23 of the UN Watercourses Convention, Watercourse States may be required, where it is appropriate, to cooperate with non-Watercourse States to protect and preserve the marine environment of an international watercourse.

Article 23 of the Convention stipulates that ‘watercourse states shall, individually and, where appropriate, in cooperation with other states, take all measures with respect to an international watercourse that are necessary to protect and preserve the marine environment, including estuaries, taking into account generally accepted international rules and standards’. Therefore, watercourse states are under a general obligation to cooperate with other states, co-riparian or not, if and when it is appropriate in order to protect and preserve the marine environment of an international watercourse.

For a discussion on the related obligation to protect and preserve ecosystems, see Fact Sheet #7.

No – Incorrect

Pursuant to Article 23 of the UN Watercourses Convention, Watercourse States may be required, where it is appropriate, to cooperate with non-Watercourse States to protect and preserve the marine environment of an international watercourse.

Article 23 of the Convention stipulates that ‘watercourse states shall, individually and, where appropriate, in cooperation with other states, take all measures with respect to an international watercourse that are necessary to protect and preserve the marine environment, including estuaries, taking into account generally accepted international rules and standards’. As noted in the Online User’s Guide: ‘a slight variation occurs in reference to ‘other states’ rather than ‘watercourse states’. This deviation reflects that scenario whereby states sharing a particular marine environment, but not necessarily the same watercourse, may find it advantageous to cooperate’. Therefore, watercourse States are under a general obligation to cooperate with other States, co-riparian or not, if and when it is appropriate in order to protect and preserve a particular marine environment of an international watercourse.

The Online User’s Guide goes further in describing the measures that might be deemed appropriate as including, but not limited to, ‘environmental impact assessments, monitoring, notification, information exchange and consultation, scientific and technical cooperation, assistance to developing countries, development of control strategies, and so forth’.

Such appropriate measures can be gleaned from similar global and regional agreements on transboundary water management and protection. Hence, in determining whether or not a watercourse state has fulfilled its obligation to protect and preserve the marine environment of an international watercourse each state must demonstrate that it took reasonable steps (such as those listed above) in order to achieve this outcome if and where it was appropriate. Thus, Article 23 also incorporates a due diligence element as part of the general duty.

Finally, the Online User’s Guide argues that the precautionary approach adopted in similar global and regional agreements on transboundary water management and protection would also be appropriate for use under Article 20 of the UN Watercourses Convention.

For a discussion on the related obligation to protect and preserve ecosystems, see Fact Sheet #7.