Though it is a relatively recently elaborated body of law, international water law, i.e. international rules relating to the management, utilisation and protection of shared international freshwater resources, is centred around three key rules: the principle of equitable and reasonable utilisation, widely regarded as the cardinal rule in the field; the duty to prevent significant transboundary harm; and the duty to cooperate in the management of shared waters. The effective implementation of these rules, however, infers a range of related, ancillary requirements, including various procedural rules which facilitate inter-State communication, and detailed substantive requirements which further inform the applicable due diligence standards. This model is now almost universal. However, this body of rules also continues to interact with and to be shaped by other dynamic and highly pervasive fields of international law, including international environmental law, international human rights law and international investment law. This chapter explores the evolution of international water law from the essential rules required to avoid and manage transboundary disputes over shared waters while being minimally invasive of riparian States’ territorial sovereignty, towards a more expansive corpus of law which seeks to optimise the benefits of cooperative water resources utilisation and to apportion such benefits on the basis of a distributive conception of equity. This shift in emphasis towards more cooperative measures for optimised water management is reflected in the emergence of clearer requirements for effective ecological protection of transboundary basins, and of increasingly sophisticated methodologies for achieving this end. It also examines the growing range of related norms, adopted at multiple levels and by a diversity of social and economic actors, both State and non-State, which play a crucial role in water resources management. It proceeds to outline the increasingly complex and mutually reinforcing interactions developing between international water law on the one hand and international environmental law, international human rights law and international investment law on the other.
This chapter considers the South African experiences in relation to fulfilling the right of access to water. It deals with the relevant legal framework and analyses the challenges in relation to achievement of access to water where there was no such access before; deliberate restriction of the right of access to water; and restriction of the right to water that is not deliberate. Cross-cutting issues including the amount of water regarded as ‘sufficient’ and water quality are also evaluated in relation to access to water. The South African experience demonstrates that not only provision of new water services is important, but also non-regression in relation to existing access. It is clear that law plays an important role in achieving both access and preventing undue restrictions to access, but more is needed, such as appropriate financing, good governance and, where necessary and feasible, consumer payment for water services.