Historically, international law governing the utilisation of transboundary freshwater resources has been concerned with the issue of water allocation between riparian states. The first major recorded water dispute of legal significance dates back to 1895, when Mexico charged the Unites States of America with diverting water from the Rio Grande in violation of international law.1 Before it eventually led to an agreement between Mexico and the US in 1906,2 the US Attorney General Judson Harmon had delivered a legal opinion on the state of international law, which set the scene for years to come. 3 What became known as the Harmon Doctrine the theory of absolute territorial sovereignty, granting a riparian state complete freedom of action with respect to the portion of an international river within its own territory regardless of its harmful consequences for other riparian states 4 attracted another opposing extreme; the theory of absolute territorial integrity, favourable to lower riparian states.5 Nevertheless, international law has since developed in such a way as to ensure equitable resolutions of international water disputes under the theory of limited territorial sovereignty