ADAPTATION TO ARIDITY: WATER DEVELOPMENT IN SOUTH AFRICA1

ABSTRACT The Republic of South Africa, legatee of a three-century history of recurring drought, is firmly committed to a program of the optimum use of its water for the national benefit. Its water law encourages centralized planning in that water is held to be the property of the state and is assignable without requiring acquiescence by the basin or province of origin. Interbasin diversions from the Tugela River to the Vaal River Basin, from the Orange River to the Fish and Sundays River Basins, and from several basins to Cape Town are under construction as are facilities for water importation from Lesotho and Angola. For satisfaction of demands beyond the year 2000 the nation may depend increasingly on a shift of its power production and water-using industry from the coal fields of the central plateau to nuclear power development with associated desalination along its coasts. Alternatively, and preferably, it may cooperate in a co-prosperity bloc in Southern Africa aiding the economies of its neighbors by development for mutual advantage of the water and power resources of the Okavango and other northern rivers.     

A method for determining the analytical form of a radionuclide depth distribution using multiple gamma spectrometry measurements

When characterizing environmental radioactivity, whether in the soil or within concrete building structures undergoing remediation or decommissioning, it is highly desirable to know the radionuclide depth distribution. This is typically modeled using continuous analytical expressions, whose forms are believed to best represent the true source distributions. In situ gamma ray spectroscopic measurements are combined with these models to fully describe the source. Currently, the choice of analytical expressions is based upon prior experimental core sampling results at similar locations, any known site history, or radionuclide transport models. This paper presents a method, employing multiple in situ measurements at a single site, for determining the analytical form that best represents the true depth distribution present. The measurements can be made using a variety of geometries, each of which has a different sensitivity variation with source spatial distribution. Using non-linear least squares numerical optimization methods, the results can be fit to a collection of analytical models and the parameters of each model determined. The analytical expression that results in the fit with the lowest residual is selected as the most accurate representation. A cursory examination is made of the effects of measurement errors on the method.     

WATER AS A COMMODITY IN INTERNATIONAL TRADE1

International trade in water has been pioneered by coastal or island city-states, by areas subject to boundary revision after a water supply system had been established, by informal accommodations among good neighbors, and by co-riparians agreeing to negotiate on compensation as an element in water allocation. Specific examples are described. Formulations of criteria for an equitable agreement for possible transfers of Canadian water to the United States have been published by Laycock and by Kuiper. Many other Canadians have expressed serious concern over the long-range implications of water export and have frequently proposed restrictions which they believe that Canada should insist upon in any negotiations. Explicitly or implicitly in nearly all Canadian discussion of water export is the conviction that international transfer, should it be permitted at all, should occur at some mutually satisfactory point or points on the border with all questions or sources and routes within Canada being left to the agencies within Canada selected by the Canadians for the task.     

WATER DIVERSIONS TO THE NORTH AMERICAN PRAIRIES1

ABSTRACT .The major purpose of existing and proposed diversions of water to the Prairies is for irrigation. Being flat lands adaptable to mechanized agriculture and possessing a good network of rail and highway access, they are well suited for such use. Wheat surpluses, currently a serious problem in Canada, can be expected to melt under world population pressures and conversion of wheat lands to other crops with the advent of irrigation. The water sources envisaged are in the Canadian Arctic watershed with the United States purchasing Canadian water at the boundary. There is an increasing interest in the Canadian Prairie Provinces in regarding water as a commodity and selling some of it to pay for the development required to put the portion retained in Canada to use.